THE LIBRARY OF THE UNIVERSITY OF CALIFORNIA LOS ANGELES The Uirt D. RGED LIBRARY DrPARTWENT Of GBOU»GT UWITERSITY of CALIFORNIA LOS ANGEI.ES. CA1,1F. UNIVERSITY of CAUFORNlA AT LOS ANGELES LIBRARY i •' ' ■ • » »^ EXPLORATIONS IN TURKESTAN WITH AN ACCOUNT OF The Basin of Eastern Persia and Sistan Expedition of 190^, under the Direction of RAPHAEL PUMPELLY WASHINGTON, D. C. : Published by the Carnegie Institution of Washington April, 1905 I25;n^j Xl41 CARNEGIE INSTITUTION OF WASHINGTON Publication No. 26 FROM THE PRESS OF THE HENRY E. WILKENS PRINTING CO WASHINGTON, D. C- ■I .i Ubnux ^ Archeological and Physico-Geographical Reconnaissance in Turkestan By Raphael Pumpelly A Journey Across Turkestan ... By William M. Davis Physiographic Observations Between the Syr Darya and Lake Kara Kul, on the Pamir, in 1903 . By Raphael W. Pumpelly A Geologic and Physiographic Reconnaissance in Central Turkestan By Ellsworth Huntington Y The Basin of Eastern Persia and Sistan, By Ellsworth Huntington CONTENTS. Archeological and Physico-Geographicai, Reconnaissance in Turkestan. Page. Introduction 3 Itinerary 3 Outline sketch of the region 5 Evidences of former occupation 7 Tumuli (or kurgans) ." 7 Ancient towns 9 Ruins near Atrek River 9 Ancient Merv 10 Ruins of Paikent 10 Samarkand lO Review of the field 12 Results in physical geography 16 Recommendations 18 Town sites 18 Tumuli 18 Summary ig A Journey Across Turkestan. Itinerary 23 Nature of observations 23 The Caspian region 24 The Tertiary and Quaternary Caspian 24 The Bosporus 26 The south coast of the Black Sea 26 U-^ The Quaternary Caspian shorelines near Baku 28 '' The Quaternary shorelines near Krasnovodsk and Jebel 33 The plains of Southern Turkestan 36 1/ The Quaternary Aralo-Caspian in the Kara Kum 37 The piedmont plains 40 The Akhal-tekin oases 41 The Kopet Dagh 46 The Firuza Basin 47 The Serani Valley 49 The Selsuparali Basin 50 The terraces of Duruigar Valley 52 The desert plains 54 The aggrading rivers of the plains 55 Loess deposits 58 Loess near Samarkand 58 Loess near Jizak 59 Loess in Fergana 60 Loess dn Semiryetshensk 61 Loess in (western) Kugart Valley 63 The Tian Shan Mountains 64 Preparation for the mountain journey 64 Route over the mountains 67 V VI CONTENTS. The Tian Shan Mountains — Continued. Weather, climate, and vegetation in the Tian Shan 70 Development of the Tian Shan Mountains ' 72 The Bural bas-tau y^ The Kokta] Range and the Son Kul Basin 74 The ranges near Issik Kul 74 The ranges and steppes of Semiryetshensk and Semipalatinsk 77 Origin of the existing ranges of the Tian Shan 80 The bearing of the Tian Shan ranges on the theory of horsts 82 Glacial records in the Tian Shan &} Moraines near Son Kul 84 Moraines in the Terskei Ala-tau 86 Moraines in the Kungei Ala^au 87 "^ Subdivision of the Glacial period 88 " Glacial erosion in the higher ranges 89 The Narin Tertiary Basin 02 The period of deposition 02 The period of deformation and erosion ■ 03 The rivers and valleys of the Tian Shan pj Rivers of the Issik Kul district ng " The Kugart terraces P7 The terraces of the Narin Basin 102 ^ ■ Origin of the terraces 103 The Issik Kul Basin 105 The early basin deposits 105 The piedmont slopes and valleys 106 I- The recent changes of Issik Kul log • Relations of the river Chu to Issik Kul 1 1 1 Notes on archeology 114 / Conclusion 117 List of references 118 Physiographic Observations Between the Syr Darya and Lake Kara Kul, on the Pamir, in 1903. Description of the route 123 Detailed observations 132 In the Alai Valley 13-3 In the Kizil-Art Valley 136 Moraines 137 On the Pamir 138 Ancient shorelines and sediments of the Great Kara Kul Basin 138 Observations on the glacial geology of the Great Kara Kul Basin 140 The Kara Jilga moraine 142 Observations in the region of Kizil Kul 143 Fluctuations of lake level and glacial advances explained by climatic changes 143 Glacial epochs 145 Form of the great Alai Valley 146 The valley itself 146 Side tributaries 146 Explanation of conditions 147 Observations in the Taldic Valley 148 Observations on the southern border of the Fergana lowland plains 151 Attempt at correlation of recent geology of the mountains and plains 153 Miscellaneous observations on the lowland plains ISS Conclusion 155 CONTENTS. VII A Geological and Physiographic Reconnaissance in Central Turkestan. p^^^ Itinerary 159 Plan of report 160 The Paleozoic series 160 The Mesozoic-Tertiary series 163 ■ Comparison with American formations 166 The Tertiary peneplain 167 The Quaternary uplift 169 Consequent drainage . . '. '. 169 Long continuance of processes of deposition and uplift 170 Physiographic provinces 171 The Tian Shan Plateau 171 The Kashgar Basin 175 Subsidiary basins 176 Loess 178 The Alai Mountains 178 The Alai Valley 179 The Fergana Basin 181 The Quaternary period 182 Glaciation 182 Distribution of glaciers and amount of erosion 182 The subdivision of the glacial period in Asia 183 An older and a younger glacial epoch 184 Five glacial epochs 186 Moraines of the Jukuchak Valley 186 Moraines of the eastern Khoja Ishken Valley 187 Moraines of the Mudirum Basin igo Moraines of the Yak Tash Basin 192 Moraines of the Kan Su Valley 193 Moraines of the Taka Valley 196 Summary of the glacial period 199 Comparison of the glaciation of Asia with that of America and Europe 200 Terraces 201 Lakes 208 Sunnnary 214 The Basin of Eastern Persia and Sistan. Introduction 219 Route 220 Literature 221 Outline of report 222 The physiography of Eastern Persia 225 Climate : The cause of the desolation of Persia 227 The basin region of Iran 230 The tvvo basins of Iran 230 Geological history of the basins 232 Illustrations of the geological history of northeastern Persia 233 The mountains of Khorasan 233 Kopet Dagh 233 The Meshed Basin 235 The Kuchan earthquake 236 The Binalud range and the ncigiiboring basins 237 The Afghan depression 237 The Heri Rud Valley 237 The extinct lake of Zorabad 239 The Afghan depression south of the Russo-Afghan boundary 240 V VIII CONTENTS. Page. The Tertiary history of the basin of Eastern Persia 242 Persia as a typical example of an arid country 246 The cycle of erosion and deposition in Persia 246 Youth 246 Maturity 247 Old age 251 Persia as an example of the influence of changes of climate 253 ]/ Theories of terrace formation 254 Examples of terraces 254 The northern slope of Kopet Dagh 254 The Murg-ab River 257 The Heri Rud 258 Tlie lake of Kogneh Nemeksar 260 The Salt lake of Pul-i-Khatun 263 Nemeksar, or the playa of Khaf 264 Kulbcrcnj 265 Terraces among the mountains from Meshed to Birjand 266 The terraces on the borders of the Dasht-i-I,iit 267 Terraces in Turkey 271 Terraces in North America 272 The nature and the method "f action of the Quaternary climatic changes of Eastern Persia. 273 Sistan 276 The Helmund River 276 Description of Sistan 277 The delta of the Helmund 281 The Shila and the Ciod-i-Zirrah 283 The Quaternary era in Sistan 285 The deposits of the lake of Sistan 285 Lake deposits versus playa deposits 286 The cause of the alternations of the Sistan strata 288 Outlet theory 288 Diversion theory 288 Rhythmic warping theory 289 Fluvial or lacustral theory 290 The gravels of Sistan 291 The terraces of Sistan 293 Northwest side of the lake 293 Southeast side of the lake 295 Modern shorelines 295 Younger abandoned shorelines 295 Older abandoned shorelines 299 Climate and history 302 ■^ The ancient climate of Iran 302 Alexander's march 303 The desiccation of ancient ruins 30S Neh 306 The Merv oasis 307 Bal Kuwi and Anau 307 The northern border of the Dasht-i-Lut 308 The cause of the depopulation of Iran 308 The legendary history of Sistan 312 Agreement of legend, history, and physiography 313 Bibliography 316 ILLUSTRATIONS. PLATES. Pacing; Pftge. Plate i. Decorated pottery from the Anau tumulus g 2. Map sho»-ing route from Langar to Kara Kul 136 3. Map of Southern Turkestan 157 4. Map of Iran 217 5. Sections of lake deposits from various locations along the northwestern shore of the Lake of Sistan 284 6. Map of Sistan 288 TEXT FIGURES. Page. Fic. I. Section of the trenched tumulus at Anau 8 2. The trench in the Anau tumulus 8 3. The maul in the Anau tumulus 8 4. Section through a small muffle-shaped object in the Anau tumulus 9 5. Remains of earthen wall in the Anau tumulus 10 6. Plateau of accumulated debris of occupation in Ghiaur Kala 11 7. Paikent, a sand-buried city , 12 8. A mosque of the mediaeval Samarkand 13 9. Water-pool system in the culture accumulations of ancient Samarkand 14, IS ID. Sketch of the uplands across the Bosporus, looking eastward from near Robert College, north of Constantinople 26 11. Bird's-eye diagram of the Bosporus at its exit from the Black Sea 26 12. Sketch of headland and foreland, west of Samsun, south coast of Black Sea 27 13. Profile of elevated shorelines east of Trebizonde, south coast of Black Sea 27 14. Diagram to illustrate the occurrence of gravels near Trebizonde 28 15. Sketch map of the district southwest of Baku 29 16. An old Caspian shoreline, near Baku 30 17. Three-mile section of ridge, 6 miles northeast of Baku, looking north 31 18. The oil-wells of Bibi-Eibat, 2 miles south of Baku, looking south 31 19. A cobble spit on a ridge near Zuyk, 7 miles northeast of Baku, looking north 32 20. Rough sketch map and sections of the district about Krasnovodsk 34 21. An elevated Caspian shoreline in the Balkhan Mountains, near Jebel station 35 22. Dissected terraces at the base of the Kopet Dagh, south of the Kizil-.A.r\'at 42 23. Sand-hills near Bakharden, looking south 43 24. A barkhan near Bakharden, looking south 44 25. A village of Turkoman kibitkas, near Kizil-Arvat 45 26. Geological outline map of the Kopet Dagh, southwest of Askhabad 46 27. Terraces in the Serani Valley, looking northwest 49 28. Two-mile profile of terraces at Namali, looking east 51 29. Two-mile section of synclinal valley, southeast of Namali SI 30. Two-mile profile of terraces in the Duruigiar Valley, looking east 52 31. Scheme of terrace development S3 32. The central mound of Ghiaur Kala, from 60 to 80 feet high, in Old Mer\- s6 33. Sand dunes south of Charjui, looking northwest 57 34. Diagram of railroad cut, south of Jizak S9 35. Diagram of loess drifts, near Kara-bulak, looking south 62 36. Kambar-Ali, tlie min-bashi of Kugart 65 Z7- The min-bashi of Kugart and his men 66 38. Kuve-Gen-Shigai-ef, his younger wife, and children, and our head man, Ma'raim. . . 67 IX X ILLUSTRATIONS. Page. Fig. 39. Kuve-Gen-Shigai-ef and some of his men at Akh Tash, Son Kul 68 40. The flaHopped Bural-bas-taii, looking southeast ■;j 41. The flat -topped Bural-bas-tau, looking south j^ 42. Distant profile of the Ale.xander Range, looking west 75 43. Rough sketch map of the ranges southwest of Issik Kul 75 44. Ideal section from range C to D, figure 43, looking east 76 45. A tarentass at a station on the post-road between Vyernyi and Semipalatinsk. . . 77 46. Rough outline of the Dsungarian .\la-tau, looking south 77 47. Rough sketch of a range near Abukumof Station, looking south 78 48. The rolling steppe north of Sergiopol. Semipalatinsk 79 49. The Chalai Range from Kuni-ashu Pass in the Kok-tal Range, Jooking north. ... 84 50. Moraine in the Tuluk Valley, looking west 85 51. A young moraine within the old moraine in the Chalai Range, looking north. ... 86 52. Snowfield below Sutto-bulak Pass in the Kungei Ala^au, looking southwest. ... 88 53. Profile of a cirque at the head of a normal valley 90 54. Cirque in the Kalkagar-tau 90 55. Cirques in the Kalkagar-tau 91 SO. Cirque near Sutto-bulak Pass, Kungei Ala-tau 91 57. General cross-section of the Narin formation, looking east 92 58. A small monocline in tihe Narin formation, looking east 93 59. Three-mile section through Ulu-tuz gorge, looking east 93 60. The Alabuga Valley, looking north 94 61. Four-mile section across the northern border of the Narin formation, looking east. 95 62. Fifteen-mile section across the Kach-kar Basin, looking east 96 63. Terraces of the (western) Kugart, looking northeast 98 64. Three-mile section across the (western) Kugart Valley, looking northeast 99 65. Gorge of Dhe (western) Kugart, above Taran Bazaar, looking east 99 66. One-mile section of gorge in the (western) Kugart Valley, looking northeast. . . 100 67. Upper terrace of the (eastern) Kugart, near the Kirghiz Bridge 100 68. Gravel bluff in the terraces of the (eastern) Kugart, looking south loi 69. Ten-mile section of a landslide in the (eastern) Kugart Valley, looking northeast. 102 70. Two-mile section of terraces in Alabuga Valley, looking east 102 71. Three-mile section of terraces at the junction of the Alabuga and Narin rivers. . 103 72. Ideal section of terraces 104 73. A drowned vaJley in the plain at the east end of Issik Kul, looking northeast. . . . 108 74. Shorelines of Issik Kul at the northwest end (A), the middle (B), and the northeast end (C) of the lake 109 75. Diagram of the relation of a valley, the raised beaches, and the present shoreline of Issik Kul no 76. Profile of the Issik Kul shorelines on a granitic headland, looking west in 77. Effect of tilting on an inclosed lake ; uplift on the right 112 78. Effect of tilting on an inclosed lake; uplift on the left 112 79. Stone circles near Lake Son Kul 114 80. A carved stone on the plain at the east end of Issik Kul, looking south 116 81. A skeleton map of Fergana 123 82. Map of the Pamir, taken from Sven Hedin's map 124 83. A Kirghiz caravan on its way to the Alai Valley 125 84. A poplar tree in the Taldic Valley 125 83. Looking up the Taldic Valley at the entrance to the broad plain of Ak-Busa-Ga. 126 86. Ak-Busa-Ga 127 87. Looking across the Alai Valley to the Trans-Alai Mountains 127 88. The Kirghiz in the Alai Valley 128 89. Looking down the Kara Kul from Uy Bulak Pass 130 90. Deflated bowlder of granite 131 ILLUSTRATIONS. XI Page. Fig. 91. Deflated bowlder of granite, hollowed side facing east 131 92. A talus-shrouded mass of crystalline limestone 131 93. A glacial bowlder of crystalline limestone cracking from the changes of tem- perature 131 94. Common type of weathered bowlders 132 95. A kettle-hole lake on the moraine extending from the Kurumdi mass trans- versely into the Alai Valley 133 96. Section of Alai Valley transverse moraine 134 97. Ideal section of " twice troughed " valley 134 98. Section across Kizil-Art Valley at Bor Daba, looking north 135 99. Profile to show moraines and terraces of the Kizil-Art Valley 136 100. The northern peninsula of Kara Kul 138 loi. An east- west section of the Kara Kul Basin 139 102. Section of Kara Kul sediments exposed in hillock bluff 139 103. Moraine of the Kara Kul Basin, looking northwest to the older moraine 140 104 and 105. Sediment pushed up by an overriding moraine 141 106. Concretionary growths of calcium sulphate 141 107. Looking north from the front of the Kara Jilga moraine to the Kizil Kul steppe. 142 108. The valley heading a little west of Kizil-Art and joining the Kizil Kul steppe.. . 143 109. Drowned valleys on the west side of the north peninsula 144 1 10. Section looking north up the Sari Tash Valley 147 111. The eastern side of the Sari Tash Valley from about 5 versts below Katin-Art Pass 148 1 12. Remnants of Floor A, as seen looking down from just below Taldic Pass 148 113. Taldic Valley terraces, looking up the Taldic Valley from Floor B, about 63 versts above Gulcha 149 114. Taldic Valley terraces, looking up the Taldic Valley from Floor C, about 46 versts above Gulcha 149 115. Map of the Ak-Busa-Ga grass plain and stream channels 150 116. Section to show double change of slope in Langar gullies 152 117. Section en route, 20 versts north of Langar, loking 15° south of west 152 118. Explanatory diagram for example in determining relative antiquity of horizons of the waste on the plains 154 119. The sharp peaks south of the Alai crest 155 120. Sketch map of Central Turkestan 160 121. Sketch map showing location of fig. 120 161 122. Folds in the limestone in the Sugun Valley, west of Shor Kul, looking west. .. . 163 123. Ripple-marks on the lower half of the pink sandstone near Kan Su 164 124. Cross-section of the Tian Shan Plateau 172 125. Scene in the Yak Tash Basin, in the northern part of the Tian Shan Plateau. . . 173 126. View of the Tertiary strata on the edge of the Kashgar Basin 175 127. Fault scarp on the southern side of the Kuzzil Oi Basin, with a smooth deposit of silt lying in front of it 176 128. Drainage of the Kuzzil Oi and Min Yol basins 177 129. Gorge of the Ispairan in its lower portion 179 130. Limestone gorge of the western Kichik Alai 180 131. Longitudinal section of the Khoja Ishken or Kok Su Valley 187 132. Youngest gorge in the Khoja Ishken 188 133. Marble bowlders and beginning of the gorge associated with the fourth Khoja Ishken glacier 189 134. Cross-sections of the Khoja Ishken Valley 190 135. Cross-sections of the three gorges of the Khoja Ishken Valley 190 136. Sketch map showing the location of the Mudinmi moraines 191 XII ILLUSTRATIONS. Ptt|?e. Fig. 137. Cross-section of the Kan Su Valley at an elevation of 1 1,000 feet 194 138. Plan of the moraines of the Taka Valley iq6 139. Cross-section of the Taka Valley, looking north 197 140. View down the Kuzzil Su on the eastern border of Bokhara, showing a gravel- filled valley which has been re-excavated 203 141. Terraces and meanders of another Kuzzil Su near Chadir Kul, on the Tian Shan Plateau, at an elevation of 1 1,000 feet 204 142. Terrace wall of the Kan Su, west of Kashgar, showing horizontal gravel above tilted Mesozoic strata 205 143. Terraces of the Kok Kiya, on the Tian Shan Plateau, at an elevation of 11,500 feet 206 144. Cross-section of the Ispairan Valley, showing successive periods of cutting and filling 207 145. Shor Kul, looking south 209 146. North and south section of the plain of Shor Kul from the lake to the moun- tains of Dungsugot 212 147. Cross-seotion of a valley cut in the silt at Dungsugot 212 148. The gravel-covered lacustrine deposits at Dungsugot, illustrating the same features as the preceding diagrams 213 149. Windmills at Tabas 228 150. Horizontal section of a Persian windmill 228 151. Ruins at the Mil-i-Kasimaibad, near ZaJiidan 229 152. Sketch map of the double basin of Iran 231 153. The ruins of Old Kuchan 236 154. North and soutli section along the Heri Rud at Pul-i-Khatun 238 155. Section near Kliitayi, on the southern border of the 2U)rabad Basin 239 156. North and south section along die Anau Brook, across the Anau fault block. . . 255 157. Terraces of the Heri Rud, near Khatayi 260 158. Sketch map of Kogneh Lake and the Jam Basin 261 159. A slightly terraced valley in the mountains of Binalud Kuh, 30 miles north of Turbat-i-Haideri, March 3, 1904 266 160. Terraces in the valley of Haji Plussein Beg in the Ohahak Basin 267 161. The town of Bajistan, looking east 268 162. Terraces at the northeastern corner of the Bajistan Basin 269 164. A typical portion of the gravel desert northeast of Sistan 278 165. A raft of reeds poled by a sayid, or " fowler," on the edge of the swamp of Sistan. 279 166. An arm of the Lake of Sistan 280 167. Canals in the delta of the Helmund at Sistan 282 168. Ideal cross-section of the mesa of Kuh-i-Khoja 286 169. Ideal cross-section of the lake terraces and bluffs on the northwest shore of the Lake of Sistan 294 170. Lacustrine bluffs and recent sand dunes near Seh-kuheh 296 171. Abandoned beach and lacustrine bluffs at Sebazkim 297 172. Old lake beach at Sebazkim, looking wes-t 298 173. Ideal cross-section of the old lacustrine beaoh at Sebazkim 298 174. Sketch map of the ancient shore features in the Bay of Sebazkim 299 ARCHEOLOGICAL AND PHYSICO-GEOGRAPHICAL RECONNAISSANCE IN TURKESTAN Archeological and Physico-Geographical Reconnaissance in Turkestan. BY Raphael Pumpelly. INTRODUCTION. At the end of 1902 the Carnegie Institution voted a grant to nie "for the purpose of making, during the year 1903, a preliminar}- examination of the Trans- Caspian region, and of collecting and arranging all available existing infonnation necessar>- in organizing the further investigation of the past and present physico- geographical conditions and archeological remains of the region." The investigation was proposed because (i) there is a school that still holds the belief that central Asia is the region in which the great civilizations of the far East and of the West had their origins ; and (2) because of the supposed occurrence in that region, in prehistoric times, of great changes in climate, resulting in the fonnation and recession of an extensive Asian Mediterranean, of which the .\ral, Caspian, and Black seas are the principal remnants. It had long seemed to me that a study of Central-Asian archeolog\- would probably yield important e\-idence in the genealogy- of the great civilizations and of several, at least, of the dominant races, and that a parallel study of the traces of physical changes during Qxiaternar)- time might show some coincidence between the phases of social evolution and the changes in enviromnent ; further, that it miglil be possible to correlate the physical and human records and thus funiish a contri- bution to the tinie scale of recent geology. At my request Professor William M. Davis assumed charge of the plnsico- geographical part of the preliminary reconnaissance. ITINERARY. I left Boston March 18, accompanied by Mr. K. W. Pumpelly as assistant, and stopping over at London, Paris, and P.erlin, reached St. Peter.sburg on April 23. There I had to remain several weeks to perfect arrangements and obtain the papers nece-ssar}.- for an extended journey in Turkestan. On May 15 we left St. Petersburg, with Mr. Serge de Brovtziu as interpreter, and having been joined at Baku by Professor Davis and Mr. Ellsworth Huntington, a research assistant of the Carnegie Institvition of Washington, we cro.ssed the Caspian. I found throughout our sta>- in Turkestan that orders had been sent froin St. Petersburg to assist the expedition in all ways, and ever) thing was done to facilitate 4 i;Xl'l,ORATIONS IN TURKKSTAN. tlie work. Prince Hilkofs orders (>l)tained for us tlic continuous use of a car throughout our stay in Turkestan. While I became deeply indebted to the general hospitality of all with whom we came in contact, I am under special obligations to several gentlemen to whose ready assistance the expedition owes much of its success. From their excellencies Count Cassini and the Hon. Joseph H. Choate, Assistant Secrctan- of State Mr. Herl)ert Pierce, and Baron \-on Richthofen I reccixed \alual)le letters to St. Petersburg. There, from His K.xcellency Mr. Semenof, vice-president of the Imperial Geograph- ical Society, 1 had letters of great importiuice to high authorities in Turkestan, as well as from Generals Stubendorf and Artemonof. Valuable assistance was rendered b}- Mr. McCormick, our ambassador, and Mr. Ridler, secretar}- of the embassy. Their Excellencies Prince Hilkof, Minister of Ways and Communications ; Mr. Plehve, Minister of the Interior, and Mr. Yermolof, Minister of Agriculture, gave me circular letters to all the employees of their departments ; while from the office of the Minister of War, who has control of Turkestan, orders were telegraphed to extend any desired aid to the members of the expedition. ]\I)- plans were also cordially furthered by the Imperial Academy of Sciences at St. Petersburg, which passed a resolution asking the Minister of the Interior to facilitate our journe>- ; by Mr. Karpinsky, then director of the Imperial Geological vSun'ey ; Professor Schmidt, and Mr. Bogdanovitch, and by Mr. Tchernachef, now director of the Imperial Geological Sur\'e)'. In Turkestan we enjoyed the hospitality and assistance of their Excellencies the Governor-General and Madame Ivanof ; General Mediusky, governor of Sam- arkand; General Nalifkin, vice-governor of Fergana, and Madam Nalif kin ; (General Ussakovsky, governor of Transcaspia; Colonel and Madame \'olkovnikof, local governor of Krasuovodsk ; Colonel Kukol-Yasnoiwlski, governor of Askhabad ; General Ulianin, director of the Trans-Caspian railwaj- ; General Poslovsk}-, General Gedeonof, and Colonel Poulovtsoff. I owe the success of our Pamir expedition largely to the active interest and help of Colonel Zaitza, governor of Osh. To Baron Cherkasof, political agent at Bokhara, I owe nuich for his kindness during my visit to that place. At Old Mer\' we were entertained with great hospitality bj- Mr. Dubosof, superintendent of the Imperial estate. Using the railroad as a base and having horses and escorts wherever needed, we made flj'iug excursions to many points, at different distances from the railroad, both in going and coming. From Askhabad we made an excursion across the mountains of Khorassan into Persia, accompanied by Mr. Yanchevetzki, the secretar)- of the governor, and his intimate acquaintance with the water problems and with the countrj- from the Aral south was of great use to us. On our return to Askhabad we were joined by Mr. Richard Norton, who accompanied me throughout the journey. The next stop was at Old Mer\', where we spent sex-eral days among the exten- sive ruins. Thence, passing by Bokhara, and making only a preliminary visit to Samarkand, we went to Tashkent, the residence of the governor-general of Turkes- tan. Here the party divided. Professor Da\is and Mr. Huntington going eastward SKICTCH OF TIIK UKCION. 5 to Issik Kill, where, after a month of joint work, they separated, Mr. Davis returning to America via Omsk and St. Petersbnro;, and Mr. Huntinj^ton going on to Kashgar. After Taslikent, I visited Marghilan and Andizhan, the end of tlie raihoad. Continuing our journey to Osh, at the entrance of the mountain region, we organized an expedition to the Pamir, with the courteous aid of its governor, Colonel Zaitza. The wa\- to the Pamir covered part of the route and two of the passes, the Terek and Taldik, in one of the great currents of ancient trade between China and western Asia, and it promised light on the physico-geographical part of our problem. After returning from the Pamir we visited tlie ruins of Ak-si, in the northern part of Khokand, beyond the vS\r Dar)a, and examined the mined sites of Samarkand, and of Paikent in Bokhara and a trenched tumulus at Anau near Askhabad. Throughout the journey, both by rail and in the side excursions, we had occasion to note the existence and position of a great number of former sites of occupation, both towns and tunuili. It had been my wish to examine Balkh, the site of ancient Bactra, and other ruins of northern Afghanistan, but this was found to be impossible on account of the hostile attitude of the Afghans toward even Russians. OUTLINE SKETCH OF THE REGION. A glance at a map of the Eurasian continent shows that the three seas, the Aral, Caspian, and Black, occupy parts of one great basin, bounded on the south and east by great mountains, and on the north by the Aral-Arctic divide. If the Bosporus were closed and there should exist a continued excess of rainfall o\-er evaporation, these seas would merge and the basin would fill till it overflowed into the Northern Ocean. The area of tliis Asian Mediterranean woidd be detennined by the height of the northern divide, which is as yet unknown. In any e\ent, it would be sufficient to submerge a large part of southern Russia and much of Russian Turkestiin. If, on the other hand, there should be a continued increase of excess of e\-apo- ration, the seas would dp*- up ; the whole basin would be transfonned into a \-ast desert, on the borders of which the retreating river mouths would be lost in the sands. Turkestan, once largely covered by water, is now in a .state approaching this condition of aridit\-. The greater basin is broken up into smaller, disconnected ones, of which only the Black Sea has an outlet. The Aral stands 159 feet above the ocean, the Black Sea practically at ocean level, the Caspian 84 feet below ocean le\el. The great \'olga and several small streams reach the Caspian ; east of the Caspian only two rivers, the Syr and AmuQaxartes andOxu.s), reach the Aral; and they gather water only at their sources in snow-clad mountains ; all other streams are consumed by direct evaporation and irrigation and have short courses, ending in desert sand. According to Schwartz, al)out three-quarters of all this va.st region is desert and one-quarter is capable of sujiporting the herds of the nomads. Water can be distributed on about 2 per cent of the entire area, on land free from drifted sands. 6 EXPLORATIONS IN TURKKSTAN. Along the base of the southern mountains stretches a chain of narrow oases at the mouths of the mountain valleys ; there are other very narrow strips alonj^ the larger river courses, and more extensive areas inclosed between the projecting spurs of the eastern mountains ; all the rest of the basin has become the pre>- of the mo\ing sands, which are still ver\- slowly but surely invading the oases. The boundary is sharply defined ; within it is high cultivation ; beyond it is a sea of waves of sand. As they extend eastward the southern mountains increase in height, till both they and the great spurs of the Tian Shan, giant snow and ice co\-ered crests and peaks, dominate the oases which are the offspring of their waters. It is on these mountains of snow and ice that the life of the whole region is and has been from a remote period absolutely dependent. This life is also limited by another factor — itself a result of the desiccation — the moving sands. For, other things remaining equal, while the shrinkage of the water areas can continue only till equilibrium between supph' and evaporation is reached, and while there might be also cyclical periods of revivif\'ing afflux, these compensations are offset in the oa.ses by the slow but steadily overwhelming pro- gress of the sands. The progressive desiccation of Turkestan is shown by direct obser\-ations during the past centim-, by artificial landmarks, by historical statements, and by natural records. The Aibughir Gulf of the Aral was 133 kilometers long and 3,500 square kilometers in area in 1842, and dr^' land in 1S72. The vohime of the Svr Darva has diminished greatly, as shown by the remains of old irrigating canals along its whole lower course, which are now too high to receive water. The statements of Arabian writers show that, within recent histor- ical times, there was a far more numerous population than the country could support now, when all available water is utilized. Old water-level lines occur at various heights up to 225 feet above the Aral. The progress is not uniform, but is broken by periods of temporarily increa.sed precipitation. Dorandt measured in 1874-75 a fall of 70 mm. in the year in the Aral Sea. Schultz, in comparing his surveys of 1880 with earlier maps, found a lowering of the level of 38 cm. in nine years. On the other hand. Berg, in 1901, comparing the gage established by Tillo, found the level 121 cm. higher than in 1874. He calculates the total rise between 1882 and 1901 to be at least 3 meters, or 178 nun. yearly. Judging from our observations and from those of others, especially of the Arabian writers and of the later Russian explorers, it would seem that the country- has long been an interior region, dependent for its life mainly on the snows and glaciers of the mountains ; that there have been within the present geological period great fluctuations in the amount of water derived from the mountains, as recorded in high and low shorelines of the seas and in the strata containing living fonns left by difTerent expansions of the united waters of the Aral and Caspian, and that man already existed within the region during at least the last great maximum of moisture. ANCIENT SITES. 7 EVIDENCES OF FORMER OCCUPATION. In our earliest historical records we find the countr}" occupied as now by dwellers in numerous cities, surrounded by deserts in which lived nomad peoples. The town dwellers seem to have been at least largeh- of Arjan stock and the nomads of Turanian. Who were the contemporaneous and the successive dwellers in the man\' towns? To what different races may they have belonged? Whence did they come into the land ? What were their civilizations and what their relations to other civilizations and to those of the modem world ? These are our questions, and they can be answered onl\- to a greater or less extent b\- a study of the results of exca\-a- tion and in the concentrated light of comparati\'e science in archeology, ethnology, and language and of survivals in arts and customs ; for the answers to some of these questions will be found rooted deep in the human strata of the ancient world. Asia abounds in the fragmentary survivals of stocks, arts, customs, and languages. The vestiges of fonner occupation by man are varied in character — in the eastern mountains are pictographic inscriptions recalling those of American abo- rigines, some rock sculpturing, and rough stone idols. At Lake Son Kul Profes.sor Davis describes stone circles, recalling .some of the dolmen-like forms, and at I.ssik Kul submerged buildings were reported in the lake. Along the river courses are abandoned canals which can no longer be supplied with water, and the Russian maps abound in indications of ruined towns, '' forts," etc. The most important remains are the tumuli and the towoi sites. TUMULI (OR KURGANS). The tumuli proper are accunuilations of earth, of rounded, generally synunet- rical fonn, often more or less elliptical in horizontal section. We met with them first along the base of the mountains east of the Caspian, but I saw none at a lower elevation than 250 feet above that sea. From this point ea.stward they abounded, with some interruptions, as far as to near Andizhan. (Tcnerally the}- were large — 100 to 200 feet long and 30 to 50 feet high. They are nuich more abundant ea.st of the Oxus than to the w'est. At one point I counted fifteen in sight at once. Resides these larger tumuli, there are, especially along the Syr Dania in Fergana, localities with a great number of small mounds a few yards only in diameter, suggesting burial after battles. Mounds more or less resembling the larger ones are described by De Morgan at points in northern Persia, and they occur through southern Siberia and on the plains of southern Russia and of Hungary-. In all these countries they probably have different origins — different reasons for their existence. Those in Siberia and on the Black Sea have been extensively excavated. There has been some un.satis- factor\- excavation of those in Turkestan, mostly with unrecorded results. The kurgan at Anau, near Askhabad, which was trenched some years ago by General Komorof, afforded the best exposure of internal structure. It is nearly 200 feet long by 40 feet high and slightly elliptical in horizontal section. It consists of fine, horizontalh- stratified la\-ers of made earth. Layers of silt and broken col)bles 8 EXPLORATIONS IN TURKESTAN. alternate with la)-ers rich in g-ray ashes and charcoal, and others of closely matted fragments of potter\-. Animal bones, teeth, and jaws, some of which are partially ailcined, occur frequently in all layers, with a few human bones and skulls. Sev- eral whole \ases and muffle-sliaped chests, made of coarse pottery mixed with dung, had been cut bv the trench. These apj^eared to contain only fine ashes and char- coal. Most of the fragmentary pottery is of this coarse quality, but there are also, even at the bottom of the trench, many fragments of finer te.xture, decorated with , Clay walls over which the strata bend Fig. I. — Section of the Trenched Tumulus at Anau. simple designs of l>lack on red. We found sc\cral granite stones with cnn-cd- plane surface, which had evidently been shai)ed for mealing grain by the Dictate method, and also a roughly spherical stone, which had apparently been pierced for the insertion of a handle, then to be used as a maul. The whole character of the timuilus shows that it grew from the plain upwards, as a slow accmnulation of the debris of long occupation. Tlie fact that the layers, even at the top, extend hori- zontally to the edges pro\-es that it was fonncrly flat-topped and much larger, for had it dming occupation ever assumed a spherical surface the gro\rth would have Fig. 2. — The Trench in the Anau Tumulus. Fig. 3. — The Maul in the Anau Tumulus. been in concentric lasers. The same reasoning would show that it was ne\er abandoned for a long time and again occupied. Since its surface has not been gullied, it seems possible that it was shaped by wind action, although the earth is somewhat finnly cemented. General Komorof found one celt of quartzite and some needles of bone, but absolutel\- no metal. Of the bones, I sent a representative collection to Professor Zittel, in Munich, for determination. One peculiar feature in the structure is the interruption and bending over of the layers at the two apparent earth walls. (Fig. 5.) Turkestan. Plate 1. DECORATED POTTERY FROM THE ANAU TUMULUS. TAKEN FROM THE SIDES AT BOTTOV OF TRENCH ABOUT 10 FEET ABOVE LEVEL OF PLAIN. 1903. ANCIENT SITES. 9 Se\-eral other knrgfans that we examined, which had been partially cut awa\- for brick-making, etc., and .some of these were much larger and higher than that at Anau, showed tlie same horizontal stratification of earth, burnt earth, a.shes, charcoal, and fragments of bones and of pottery. In the upper part of some of these we obser\-ed traces of walls of unbunied bricks. The onh- artifacts found in Fig. 4. — Section through a Small MufBe-shaped Object in the Anau Tumulus. these were the simplest form of flat stone for grinding grain (like those found in the Anau kurgan) and some flat stones, each with a hole drilled wholh- or partially through it from both sides. ANCIENT TOWNS. The absence of easih' obtainable stone for constniction throughout the low- lands of Turkestan determined the use, almost exclusiveh-, in constniction, of clay, both unburned and burned. Unburned clay predominated innnenseh-, used both as sun-dried bricks and in hea\y layers of raw clay. In consequence of this, all ruins older than a late Mussulman period are represented only b\- accunuilations of earth filled with broken pottery and fragments of burned bricks. These accumu- lations are flat-topped mounds, ranging up to half a square mile or more in area and from 15 to 20 feet upward in height, and in places, as at ]VIer\-, occurring in groups covering man}- square miles. They occur within areas in which now, or formerl}-, water was accessible, and are found iiho more or less buried in sands beyond the mouths of the retreating rixers, in places once fertile and now desolate. Ritiiis near A/rck J\iztr.—\ t\pe of regional desolation and abandonment is in the territory' between the lower Atrek and the Caspian. Here, over an area of many .square miles, are the ruins of cities, 30 or 40 miles from the river Atrek, the lO EXPLORATIONS IN TURKESTAN. nearest water, and in the heart of the desert. The remains of canals show that the cities were watered from tlie Atrek, but the ri\er now lies too low to feed the canals. Ancient Mcrv. — The ruins of ancient Merv are said to cover about 30 square miles and consist of several cities of different a- fertile oasis of the Zerafshan River, it lies also on the most open and easiest caravan routes connecting China and eastern Turkestan with Afghanistan, India, and Persia. Samarkand has, e\-en within the past two thousand \ears, been sacked, destroyed, and rebuilt man\- times. Like Mer\-, its rebuildings have often been on adjoining sites, and the determining of the whole area covered by these various sites remains to be made. There is evidence that it is ver>- extensive. The most ancient seems to be the plateau or "tell" called "Afrosiab," to which tradition assigns the site of the vSamarkand Maracanda of Alexander the Great. This is a plateau of "made earth," the dclms of niins, standing on the "loess" plain. It is covered to a great extent with .M(^hannnedan cemeteries, with some traces of Mussulman Fig. 6.— Plateau o( Accumulated Debns of Occupation m Ghraur Kala. occupation, and with fragments of potter\- and of bricks. The loess plain is deeply dissected b}' a stream, and several gullies have been cut in both the plateau of the ruins and the loess. It is difficidt to distingiiish between the "made earth" of the plateau and the underlying "loe.ss," except through the presence of fragments of pottery, charcoal, and bones. We found such fragments down to a depth of about 40 feet below the general surface, in the gullies, and it is not improbable that the thickness of debris is still greater. Abo\c this general surface rises the citadel mound to an additional height of 30 to 40 feet, or 170 feet abo\-e the stream at its base. Judging from the excel- lent topographical map of Afrosiab, of the general staff, the loess plain lies about 50 feet above the stream. This would make it possible that the citadel mound repre- sents an accumidation of over 100 feet of debris. The surface of the rest of Afrosiab is vers- irregular. While in general it ranges from 100 to 140 feet above the stream, 12 EXPLORATIONS IN TURKESTAN. there are numerous depressions, the bottoms of which arc level plains, 150 to 300 feet in diameter, standiiif,' 70 to 80 feet above the stream. The s,a'neral arranjjement of these depressions is such that if filled witii water thev would fonn a connected, irregular system of water-basins ; and there is a clian- nel about 100 feet wide which opens out on the stream valley, after coninninicating with most of the depressions. It all suggests a former water s>steni maintaining pleasant pools like those which still form an attractive feature of Bokhara. The fonner walls of the city are represented now by ridges rising 20 or 30 feet above the surface within. Where the walls are cut by gullies old galleries are exposed which seem to luu-e been continuous with the wall. Quintus Curtius states 70 stadia as the extent of the walls in the time of Alexander. This, if the short stadia were meant, would be about 3 miles, which would be approximately the cir- cumference of that jDart of Samarkand now called Afrosiab. As in all Turkestan, so at Samarkand, the older structures still standing are those of the Mohannnedan period. The man\- innnense and wonderfully decorated Fig. 7. — Paikent. a Sand-buried City. mosques built l)y Tamerlane, though now falling into ruin, belong among the wonders of the world ; and this not only on account of their great size, but also because of the licauty of their decoration. vSeen from Afrosiab, these ruins tower high above the rich foliage of the oasis city — e\idence of the wealth of treasure that Tamerlane had accumulated in Turkestan within two centuries after Genghis Khan had sacked the country and massacred nuich of its population. REVIEW OF THE FIELD. What I have been able here to sa)' regarding the archeolog\- of Russian Tur- kestan seems but a meager statement ; but it was soon clear that all that could be accomplished in such a reconnaissance would be the observation of the character and abtnidance of the evidences of former occupation, and to obtain some idea of their distribution and size. Our reconnaissance covered a territor)' nearly 1,400 miles long. It was neces- sarih' only of a preliminary character, and intended to supph' a general idea of the problems to be sol\-ed and of the best points at which to begin. REVIEW AXl) KECOMMEXDATIONS. 13 While we have been surprised at the abundance of the data in natural and ailificial records offered by the region toward these solutions, we are impressed with a realization of the intimate relation in which this region stands to the Quatemar)' and prehistoric history' of the whole continent. Physicalh- it forms part of the great interior region extending from the Mediterranean to Manchuria, whose history- has been one of progressive desiccation, but in Russian Turkestan the effects of this have been mitigated by the snows of the lofty ranges and the lower altitude of the plains. Archeologically this region has, through a long period, been a center of pro- duction and commerce, connecting the eastern, western, and southern nations, and its accumulating wealth has made it repeatedly the prey of invading aniiies. It has been from remote time the field of contact and contest between the Turanian Fig. 8. — A Mosque o( Mediaeval Samarkand. and Aryan stocks ; but its problems, both physical and archeological, are parts of the greater problem underlying the study of the development of man and his civilization on the great continent and of the environment conditioning that development. The many fragmentar}- peoples sur\i\ing in the remote comers and in the pro- tected mountain fastnesses of Asia, preserving different languages, arts, and customs, indicate a very remote period of differentiation, with subsequent long periods for separate development. The)- point also to the long periods of unrest and battling in which the survivors of the vanquished were forced into their present refuges. And this unrest was probabh- the remote protot>-pe of that which in the later pre- historic and historic time sent out its wa\-es from the Aralo-Caspian basin. It was probably from the beginning a condition in which the slowh- progressive change toward aridity in interior Asia was ever forcing emigration outward, displacing 14 EXI'LORATIOXS I\ TURKESTAN. other ])eoples, and tlius \vorkin- • ■^•.l^a' ^ Fig. 9. — Water Pool System in the C REVIEW AND RECOMMENDATIONS. 15 cities of Chinese Turkestan, and much more, of a destructive character, by others. To the north we must cross the great deserts and steppes to reach in Siberia the nearest systematic excavations of Radloff and others. In Persia, M. J. de Morgan has for several }-ears been conducting a tlioroughh- scientific investigation at several points, and especially at Susa, where he has alread^■ obtained results of the greatest interest. The acropolis of Susa is 105 feet high. M. de Morgan's preliminary tunnels, run into the hill at different levels, showed it to be composed of made earth from the base upward. Stone implements and potter)- abounded up to 36 feet from the top. The potter\- impro\-cd from below up, and among the fragments he recognized a variety- belonging to a grouj) peculiar to Egj-pt, Syria, Cyprus, and most of Asia Minor, but not known from Mesopo- tamia. De Morgan had found this in predynastic tombs in Eg>pt, and ascribed it to a period before the eighteenth century B. C. At 45 feet below the top he found tablets 'and cylinders with cuneiform inscriptions which Scheil considers as belonging to a period before the fortieth century B. C. M. de Morgan asks : " If the refined civilizations of the past 6,000 years, with their great structures and fortifications, have left only 45 feet of debris, how many centuries nuist it ha\e required to accumulate the lower 60 feet, when man used more simple materials in the construction of his abodes? " The thickness of made earth in the abandoned sites of Turkesbxu is sufficient to give reason for expecting evidences of ver>- long continued occupation. The dr)-ness of the climate makes possible the preser\'ation of an\- traces of written or incised documents that may have existed. Excavation conducted with the idea that e\er>thing met with — the earth itself, the character, position, and a.ssociation of fragments — is part of history, can not fail to be most fruitful in results. lations of Ancient Samarkand. l6 EXPLORATIONS IN TURKESTAN. It is the opinion of an important school of archeologists that the earliest prodncts of metallurgy in bronze and iron successi\-eh- progressed to the western world from the far East — a progress that in each case carried witli it a re\olution in civilizations. We do not know whether this region saw the birth of the metallnrgj' of those elemental substances which — beginning with copper and tin and progressing through bronze to iron and steel and the use of coal — marks the birth of civili- zation and its great revolutions. If it was not the birthplace of this art, and if it was a distributing center, it is a long step nearer to an\- far eastern source, whether this was China, Kast Turkestan, India, or Persia. RESULTS IN PHYSICAL GEOGRAPHY. Both our own obsen-atious and the excellent and extensive work of the Russian geologists show that the progressive desiccation of the region has greatly diminished both the area of cultivable land and the volume of water, and greatly reduced the population. Is this change a phase of cyclical phenomena — of c)-cles of long periodicit>- ? In what relation have the geologicall}- recent secular phenomena in central Asia stood to man and civilization in that region and to the outside world? One of the chief objects of the reconnaissance of the past season was to deter- mine whether a systematic investigation would be likely to throw light on these questions. Perhaps the most important result is our finding that successive physi- cal events have left such abundant records, written in large strokes, all o\-er the mountains and the plains. The work of this year has not onh* made a most promising beginning in this interpretation, but has shown that it is probably possible to correlate the different events among themselves and with the period of human occupation, and possibly with similar ph)sical e\-ents in Europe. As an interior region, central Asia is arid and dependent for its water almost wholh- on its bordering mountains. It is also self-contained, i. e.^ without drainage to the ocean. Changes of climate, resulting in great fluctuations of water supply, would therefore probably be recorded b)- old shorelines at different levels. They might also be more or less legibly recorded in the evidences of repeated glaciation and erosion in the high mountains. It will be seen from the report of Professor Davis that he has found traces of an old shoreline about 600 feet above the west shore of the Caspian Sea, and a \er>- distinctly marked one on the east side, at an elevation of 200 feet or more. Further search for shorelines was left to form the object of a more extended special stud>- than could be made in our general reconnaissance. In the eastern mountains, near Issik Kul and Son Kul, Professor Davis found clear evidence of two and probabh- three glacial epochs. Mr. Ellsworth Hunting- ton, working in the higher Tian Shan, found proof of three epochs, and later of five phases, in the successive moraines of a large number of glaciers studied by him in REVIEW AND RECOMMENDATIONS. I7 the Alai Mountains. Between some, at least, of these there were long interglacial intervals. Mr. Huntinofton reports records of climate oscillation shown not only in these moraines, but also in the vallc)- terraces, and considers them to be members of a group of sympathetic glacial phenomena. Professor Davis noted along the northern edge of the Kopet Dagh, the moun- tains bordering the plains east of the Caspian Sea, and in the eastern mountains evidence of a longitudinal dislocation, accompanied by great block uplifts, fonned apparently after the w^earing down of the mountain masses to a peneplain and preceding an active dissection of the elevated mass. This dislocation had been already observed by Muschketof, who states that it extends far along the edge of the Kopet Dagh. Mr. R. W. Pumpelly studied independently the region from the Syr Darja southward across the two mighty snow and ice ranges, the Alai and Trans-Alai. He found clear evidence of two long-separated glacial epochs recorded in extensive moraines, and, on the Pamir, in apparently corresponding high shorelines around Lake Kara Kul. These glacial epochs he has coixelated with orogenic movements of the Trans-Alai, there being a definite relation between the glacial trough bottoms of the two epochs and the present stream floors. In the Alai range, he found that there had been a block uplift followed by a block tilt, both with a dislocation through the border of the lowland plains to the north, and leaving their records in alluvium-capped hills and terraces along the valle}- sides and in the dragging up or tilting of the fluvial sediments or river fans on the lowland borders. These movements he has correlated with the glacial geology, making the block tilt an interglacial event. These block uplifts, b>- lowering the base level, caused a remodeling of the mountains, and have left their record on the lowland plains, which they have helped to create, by the vast amount of material poured out on them by the eroding streams. The block-uplifting and the tilting being correlated with the growth of the alhuial Fergana lowlands, and the relation of the glacial expansions to the \-alley- cuttings in the Trans-Alai range being clearly recorded, it becomes a matter of great interest to correlate these Quaternar}- events of the Trans-Alai \-allo\s with those of the Alai range and the lowlands, and the growth of the plains witli the progress of human occupation. It is not impossible that, by extending the study of glacial records from the Central-Asian ranges through the Elburg and Caucasus, it may be practicable to correlate Asiatic and Alpine glacial events ; and since the great basin was fed both by glaciers of the southern ranges and by the great ice cap of Russia, this correla- tion of both might be effected ; for, in view of the great orogenic movements to which the Caucasus, the Persian Mountains, and the Tian Shan have been subjected, it can not be positi\elv asserted that the Central-Asian glacial expansions were all contemporaneous with phases of the nuindane glacial epoch. 1 8 EXPLORATIONS IN TURKESTAN. RECOMMENDATIONS. Since Turkestan is under the control of the Minister of War and nuich of its frontier is closed to travelers, it is necessan.- to ha\-e the permission and good will of the goveninient in order to pursue investigations. To inaugurate anj- extensive plan of archeological excavations will require tactful negotiation at St. Petersburg. I have good reasons for believing that the desired concessions can be had on a basis of division of objects found, and with a sufficient time allowance for the study of all the material. Such a plan should include both town sites and large and small tumuli. Of town sites I would recommend the following, as points to begin on, in the order stated.: Town sites. — Afrosiab (Samarkand), Ghiaur Kala (Old Mer\'), Paikent (west of Bokhara), Aksi (on the Syr Dar^-a) ; the high ruins seen several miles to the north of Ghiaur Kala ; a ver}- high one seen from the railroad a few miles west of the Amu Dar}-a. Tumuli. — Both tlie tumulus mentioned at Anau, near Askhabad, and another a short distance from it ; others west of Askhabad, north of Old ]Mer\-, and near Jizak ; also manj- mounds of small size which seem to have a different significance. As bearing on the age of the tumuli, it is important that the relation of the base of the mound to the surrounding earth be studied to detennine by how nuich, if any, the level of the plain has been built up since the first occupation of the site, and to see also by how nnich the mound has shrunken in size at its base, as it certainly has in horizontal section at the top. In connection with the question of age of the tumuli and in relation to the last expansion of the Aralo-Caspian seas, it would be very desirable to determine the lower altitude limit of distribution. I did not .see any below 250 feet above the Caspian. Similar obsei-\-ations are needed on the west coast of the Caspian, where De ]M organ found no antiquities on the lowlands in the Lenkoran countr}-, but at a higher level abundant tombs of the bronze period and of the transition to iron. As further connected with the relation of human occupation to the fonnerly expanded water area, there is needed a detennination of the altitudes of the Manytsch divide between the Caspian and the Black Sea, and of that between the Aral and the Arctic Ocean. Both of these are now not far from railroad bases. As regards further wtjrk in physical geograjDhy, Profes.sor Davis writes : "The order in which I should like to see the * * * studies taken up on the plains, in order to define most rapidly the conditions of early human history-, is as follows : "The shorelines of the Caspian and Aral seas; first on the southwest, south, and southeast, then on the northeast and the associated plains. "The double belt of piedmont plains and bordering ranges with special work in certain glaciated valle)-s. " The deposits of loess from Samarkand to Tashkent. "The Issik Kul basin, by a special, independent part}-. "Secondarily, Block mountains and the Narin fonnation." REVIEW AND RECOMMENDATIONS. 19 SUMMARY. We have shown that the recent physical history of the region is legibly recorded in glacial sculpture and moraines, in orogenic movements, in valley cutting and terracings, in lake expansions, and in the building up of the plains, and we have made some progress in correlating these events. We have also found full confinnation of the statements as to a progressive desic- cation of the region of long standing, which has from a remote period continually converted cultivable lands into deserts and buried cities in sands. We have found, widely distributed, great and small abandoned sites of human occupation, with evidences of great antiquity. We have reason to think that a correlation of these physical and human events may be obtained through continuance of the investigation, and that archeological excavations will throw light on the origin of Western and Eastern civilizations. A JOURNEY ACROSS TURKESTAN. BY WILLIAM M. DAVIS, Sturgis-Hooper Professor of Geology, Harvard University. A Journey Across Turkestan. By William M. Davis, Sturgis-Hoopcr Professor of Geology, Harvard University. ITINERARY. Ou April 17, 1903, accompanied by Mr. Ellsworth Huntington, who had been appointed research assistant b}- the Carnegie Institution of Washington, I left Boston; sailed from New York, April 18; landed at Cherbourg, April 24; spent April 25 in Paris, April 28 in Vienna, and May i to 3 in Constantinople; crossed the Black Sea to Batoum, May 4 to 8 ; and went thence by rail to Tiflis, May 10, and to Baku ou the Caspian, where we arrived Ma}- 12. We crossed the Caspian on the night of May 22, and started from Krasnovodsk on the Central Asiatic Railway on the afternoon of May 24. After making short stops at Jebel, May 25, Kizil Arvat, May 26, and Bakharden, May 27, to examine the piedmont border of the great plains of Turkestan, we delayed at Askhabad, May 27 to June 9, long enough to make a five-day excursion. Ma)- 30 to June 4, into the Kopet Dagh, the mountain range along the Russo- Persian frontier. Leaving Askhabad by train the evening of June 9, we stopped at Mer\', June 11 to 14, and Samarkand, June 16, and on June 17 reached Tashkent, where we remained three days. On June 20, accompanied by IMr. Huntington and Mr. Brovtzine, intei-preter, I went b)- rail to Andizhan, where we stopped from June 21 to June 27, to outfit for an excursion across the western ranges of the Tian Shan Mountains to Lake Issik Knl. We set out from Andizhan, June 27 ; spent two days, July 8 and 9, at Lake Son Kul ; reached Issik Kul on July 14 ; made a short trip into the mountains on its southwestern side, and then moved along the northern shore to the Russian settlement of Sazauovka. Here, on July 22, IVIr. Huntington turned southward to begin his excursion to Kashgar, with the object of continuing over a large district of the high ranges the study of old moraines and terraces that we had begun together on the road to Issik Kul ; while I turned northward with Mr. Brovtzine and began my homeward joume}-. \'yem\i was reached Juh- 26 ; we went in tarautass to Semipalatinsk, August 2 ; by boat down the Irtysli to Omsk, August 7; by train to St. Petersburg, August 15, where Mr. Brovtzine resided ; I continued by train to Ostend and London, August 1 7 ; and by steamer from Liverpool to Boston, August 20 to 28. NATURE OF OBSERVATIONS. In the geologic and physiographic reconnaissance of the region tra\-ersed, the chief subdivisions of Turkestan were visited in the following order : The Caspian Sea on the west, the central plains, and the mountains on the south and east. 23 24 EXPLORATIONS IN TURKESTAN. While it may be desirable later to make as precise a detennination as possible of the geologfical date and of the physiographic surroundino^s of human monuments or artifacts, it did not seem advisable to combine detailed local obsen-ations with a general reconnaissance during our first season in the field. My work was therefore directed to gaining a broad view of the region and its development, from which it should be possible to plan and direct a series of more thorough studies regarding the subdivisions of later geological time, in case such studies are to be undertaken in the coming years. It is a matter of regret that, owing to the deficient represen- tation of Russian material in our libraries, it has not been possible to make as full a study of the work of earlier observers as was desired in the preparation of this report. THE CASPIAN REGION. The region traversed naturally divides itself into three parts: The sea on the west, the mountains on the south and east, and the plains between the two. The waters of the Caspian are gathered in an area of relative depression ; the mountains are the scene of active erosion because of their relative elevation ; the ri\-ers stri\-e to earn,- the waste of the mountains down the \-er\- gentle slope of the plains and deposit it in the sea. The climatic changes, well proved to have taken place over other parts of the world in later geological times, may be believed to have had their effect in this region also. The Caspian is known to have stood at a greater height and to have covered a much larger area in Quaternary- time, especially to the east and north, as is attested by its abandoned strands and shell deposits; the existing glaciers of the eastern mountains have been longer than they are now, as proved b>- their abandoned Ouaternar}- moraines, reported by various explorers ; the rivers between the mountains and the sea must ha\-e, in some way appropriate to themselves, responded to these var\'ing conditions at their two extremities, and hence even in the strata of the plains some record of Quaternary' climatic variations may be discovered. • There can be no question, however, that the record of Quaternary climatic variations on the plains would be of much more difficult recognition than in tlie mountain valleys on the east, or around the great sea basin on the west. It was for this reason that my reconnaissance was directed chief!)- to the Caspian shorelines and to the extinct glaciers of the Tian Shan, and that the study of the plains was left to a later year. THE TERTIARY AND QUATERNARY CASPIAN. The existing Caspian Sea is the successor of the expanded water body of late Tertiary time which made the Black, the Caspian, and the Aral basins confluent and which laid down a series of stratified deposits, known as the (Tertiary) Aralo- Caspian fonnation, apparently the equivalent of the Congerian or Pontic stage of Europe. These deposits are now more or less deformed and eroded ; for example, near Baku and next eastward in the Apsheron peninsula, where the Caucasus range THE QUATERNARY CASPIAN. 25 descends into the Caspian. Here a t>'pical section shows anticlinal and monoclinal Aralo-Caspian ridges, with strata dipping 20° or 30°, and crests rising from 600 to 800 feet o\er the present Caspian level. The existing Caspian is by a still greater measure of time separated from that ancestral water body in which the Akchlag^l strata of the Ust-urt plateau as described by Andrussof (1902) were laid down, these being pre-Pontic and post-Sannatian. The Tertiary seas represented by the Sannatian and Mediterranean stages (Miocene) were yet more ancient. Their deposits are so widely distributed on existing lands and so much deformed and eroded that their parent waters had little resemblance to the seas of to-da\-. The Quaternary Caspian, with whose shorelines and deposits we are concerned, is more modem than the latest of the seas above named. It does not seem to have been the immediate successor of the expanded Tertiar\' seas, for although Neumayr thought that there had been a progressive diminution of water area from Sannatian times, not interrupted by expansion even during the glacial period (1875, 32), Andrussof sa)s that at the end of the Tertiary- the Caspian was probably lower than at present (1888, 113). Our observations confinn the latter view. There must have been indeed a considerable period of late Tertiar\- or early Quateman' time when the Caspian had a lower level than now, for not only the high-le\-el Quateman,- shorelines, but even the present Caspian shorelines, contour around the eroded ridges of the deformed (Tertiar\) Aralo-Caspian strata at Baku. The low- water epoch between the Tertiar}- and Quatemar}- periods of Caspian expansion nmst have endured for a much longer measure of time than that of the Quatemar}- high-water stage and the present mid-water stage, taken together ; for the erosion that the defonned (Tertian) Aralo-Caspian strata suffered before the Quatemar\- Caspian rose upon them at Baku is hundreds of times greater than the sum of the erosions recorded in the Quatemar)- strands, and thousands of times greater than the erosion that the strands have suffered since the waters retired from them. It is also important to note that the historic oscillations of the Caspian are all short-lived events, and that their order and rate of change can not be safely used to determine the time since the high-level Quatemar}- shorelines were occupied. The Quatemar}- Caspian appears to have been confluent with the Aral on the east, as will be more full}- stated farther on ; hence the tenn Aralo-Caspian has been applied to this expansion of the sea as well as to that of late Tertiar}- time ; and it is not always easy to understand which sea is meant when this ambiguous name is emploved. The Quatemar}- Caspian was also confluent with the Black Sea, for its strands are hundreds of feet above the existing water level, while the pass between the two seas in the Man}-ch depression north of the Caucasus range is only 26 feet over the Black Sea, and 112 feet over the Caspian. It is indeed eminently pos- sible that the confluence of the Caspian and Black seas may have taken place at the time when the Bosponis was a nonnal river ; hence our passing sight of this beautiful water passage was of peculiar interest in connection with our later observations farther east. 26 EXPLORATIONS IN TURKESTAN. THK BOSPORUS. The Bosponis has been \vell described by Philippson (1897) as a young ri\er valley incised in an uplifted peneplain f'einetypische Denudationsflache"); a ver\- modem depression has changed the normal river valley to a strait, about 160 feet deep, leaving the uplands of the peneplain still from 700 to 1,000 feet above sea level. All that I saw from the steamer's deck, on two passages through the Bos- ])orus, and from a walk on the uplands back of Robert College, about 5 miles north of the Golden Horn, fully confirmed this interpretation. The defonned rocks in the walls of the gorge, the wide view over the undulating uplands with their subdued resi- dual hills or monadnocks (fig. 10), the sharp dissection of the upland by the winding main valley and its branches, and the general appearance of submerg- ence along the present shorelines, admit of no other explanation. The space available for occupation along shore is commonly so narrow that houses are often built directl)- on the water's edge. The water is so deep close to the shore that large \-essels may make near approach to the land. As a result, collisions not infre- quently occur between bowsprits and house walls ; we saw a house from which one corner had been torn out in such an encounter. The Golden Horn is simpl)- the drowned lower part of a side valley that comes into the Bosporus at Constantinople from the northwest and north. Philippson dates the erosion of the gorge as not older than the Upper Pliocene ; the depression of the region, changing the Bosporus from a river to a strait, is placed in the recent past, during the existence of man. THE SOUTH COAST OF THE BLACK SEA. Fig. 10. ^Sketch o( ihe Uplands across the Bosporus, looking eastward from near Robert College, north of Constantinople. The reasons for suggesting that the Caspian and the Black seas ma}- have been confluent before the Bosporus was submerged are based on certain indications that the land at the southeastern end of the Black Sea was lower than now at the time when the land at the southwestern end was higher. These indica- tions are as follows : The coast at and to the east of the Bosporus (fig. 11), as seen from the passing steamer, showed sharply cut modem cliflTs, but no benches or terraces above the present shoreline. The map of the region, in Stieler's Hand-Atlas, shows no delta at the south of the Sakaria River, about 90 miles east of the Bosporus. At Samsun, near the middle of the south coast, where our steamer Fig. 1 1 . — Bird's-eye Diagram ot the Bosporus at its exit from the Black Sea. THE SOUTH COAST OF THE BLACK SEA. 27 -Sketch of Headland and Foreland, west of Samsun, south coast of Black Sea, looking west. stopped for a day, the headlands to the west and east showed no elevated sea-cut benches, but they were both well cliffed with respect to the present shoreline ; a low foreland, from 300 to 600 feet wide, stretched in front of the western cliff, as in fig. 12. Whether the foreland was a slighth' ele\-ated wave-cut bench, or simply a broadened wave-built beach, I could not determine, as it was seen only from the steamer ; but in either case its attitude is inconsistent with any strong recent movement of depression or elevation. Further indication of modem coastal sta- bility in this district is seen in the large deltas of the Kyzil Innak and Yeshil Innak (the Halys and Iris rivers of ancient times), 20 miles west and east of Samsun. Stieler's Hand- Atlas makes the radius of these deltas 12 or 15 miles, although the Yeshil, the smaller of the two rivers, has a drainage basin of less area than the Sakaria, where no delta is shown. A heavj- rain fell while we lay in the roadstead of Samsun, and a stream east of the city spread its yellow flood gradually farther and farther from the shore. When the discolored water reached the steamer, half a mile from land, it still formed so thin a film that the oars of passing boats disclosed the blue water beneath. We steamed eastward past the delta of the Yeshil about sunset. It is an extensive plain, hardly above sea level, in strong contrast to the bold coast that we had seen earlier. When we reached Trebizonde, near the southeastern corner of the sea, the profile of the sloping spur next ea.st of the harbor exhibited three well-defined benches, outlined in fig. 13, which we estimated to stand 20, 100, and 250 feet above sea level; and a small stream that passed through the cit)- flowed in a narrow, steep-sided gorge. Thus there seems to be indication of a modem depression of 160 feet at the Bosporus, of no significant modem movement at Samsim, and of a modern elevation of from 100 to 250 feet at Trebi- zonde. But somewhat farther northeast, at Batum, there was again indication of stability rather than of elevation. No benches were seen there on the hillsides, but the Choruk-Su (river), of drainage area similar to that of the Yeshil, has a well- fonned gravel delta that stretches several miles forward from the end of its steep- sided valley through the mainland hills. The absence of elevated shorelines here makes it hazardous to extrapolate, towards the Manych depression and the Caspian, the indications of recent tilting that we found on the south coast. A few words may be said on the possible eastward extension of the uplifted peneplain in which the Bosporus trench is cut. The south coast of the Black Sea is submountainous. The valleys that we saw were rather sharply incLsed in uplands that sloped with moderate irregularity from higher hills or mountains in the background toward the cliffs of the shoreline. It seemed plausible to associate Fig. 1 3. — Profile of Elevated Shorelines east of Trebi zonde, south coast of Black Sea, looking east. 28 EXPLORATIONS IN TURKESTAN. these sloping uplands with the more nearly horizontal uplands of the Bosporus, and to regard them both as parts of a peneplain, with many unconsumed residuals or monadnocks, in a late Tertiary cycle of erosion. A ver^- moderate warping would suffice to have depressed part of the peneplain in what is now the basin of the Black Sea, and to have raised an adjoining part in what is now the sloping northern border of Asia Minor. The sloping uplands woxdd then be dissected by valleys, whose depth would rapidl}' increase inland, and whose sides would have a younger expression than that of the uplands in which they eroded, as was so dis- tinctly the case along those western, middle, and eastern parts of the coast that we saw. A daj- ashore at Trebizonde was gi\en chiefly to the gravels that lie on the uplands back of the cit}'. Level beds of ashy gray sands and gravels, covered with angular waste which has crept down from the next higher ledges, were found in two localities on the steep hillside about 300 feet above the sea level (A, fig. 14); Fig. 14. — Diagram to illustrate the occurrence of gravels near Trebizonde. more extensive beds of yellowish gravel (B) occurred at a height of 500 or 550 feet on the shoulders of the sloping upland where it was cut by the narrow valleys. Scattered pebbles (C) occurred at still higher levels, up to about 800 feet. These gravels have been described by Wright, who regards them as later than "the entire rock erosion of the region " (p. 249). It was not possible, in the short time at our disposal, to reach an independent conclusion as to whether the gravels were older or younger than the vallejs of the district No fossils were found in them, and hence it can not be said whether they are of marine or fluviatile origin. It should be stated that the uplifted shorelines, next east of Trebizonde, seemed to turn somewhat inland along a \-alley side; hence the relation of higher sea level and valley erosion is not a simple problem. THE QUATERNARY CASPIAN SHORELINES NE.\R BAKU. It has already been pointed out that the present shoreline, as well as the ele- vated shorelines, of the Caspian skirt an eroded surface of late Tertiar}- Aralo- Caspian strata in the Baku district. Hence the waters of the sea must ha^•e been, for a considerable part of early Quatemar}- time, lower than they are now. This lower water stand, inferred from ph)-siographic evidence, should not be confused with the lower water stand during the historical ]\Iiddle Ages, about the tenth cen- tury, as demonstrated by the occurrence of the walls of several buildings (H, fig. 15), nearly submerged a few hundred feet offshore in Baku Harbor. Nor should the CASPIAN SHORELINES NEAR BAKU. 29 rate of lowering of the Aral in the past century- be taken, as it has been by Obnichef (1890, 253), as a basis for calculating the antiquity of the Aralo-Caspian Sea ; the fluctuations of the Caspian and the Aral in modern times, or of Great Salt Lake, are episodes of the existing climate, and should not be assumed to have been in continuous progress since the middle Quatemar\-. It should be noted, however, that a long-continued tendency toward increased aridity appears to characterize the Caspian region in the historic centuries. A detailed account of recorded changes of level in the Caspian is given in Briickner's excellent summary- (1890). The story, current in Baku, concerning an old road marked by wheel tracks that descend below water level on the island of Nargin, 8 miles from Baku, appears to be without valid foundation. We visited the island and walked all around its j T- ^.jr>.i^ / 1 1 BAKU jf^fi^ 1 r / 1 1 if / > / ■* / J / ■* : \ u 1) 1? '"knW E . B A T ; ^0 : ; < ^^^y^m . " y a s5 1 1 \ % ' i % '% ^V Turkish s 11 1 1 1 P- '/ \| 1 j^^-^^ \ 1 y^ C "V V \ / 1 / ABOUT 3 MILES . / Fig. 1 5. — Sketch Map of the District southwest of Baku. shores without finding the semblance of an old road, thus unconsciously repeating the negati\-e conclusion of Eichwald and Chan>kof (cited by Briickner, 64). It is worth noting that the chief water stipply for Baku, apart from certain springs that are unpalatable to the European residents, is derived from distillation of the brackish Caspian water with cheap petroleum fuel ; the latent heat given out in condensation of the steam is economically used in wanning the next intake of water from the sea. The water works (WW) and the water tower (WT) are indicated in fig. 15. The most notable feature of the elevated Caspian shorelines near Baku is their comparative faintness. They are not marked by strongh- cut cliffs or by continu- ous benches, but by rather discontinuous benches, much less pronoiniced than the shorelines of to-day. In spite of the large size of the Caspian, its abandoned shore- 30 EXPLORATIONS IN TURKESTAN. lines are much less developed than are those of our Quatemar)- Lakes Bonneville and Lalioiitan in Utah and Nevada, or of our Laurentian C.lacial (keat Lakes in New York and farther west. The Caspian shorelines are, howexer, easil\- recognized at many points on the hillsides about Baku, where they are marked by horizontal benches of cobbles, gravel, and shells, more or less cemented, at various levels up to 300 or 500 feet (fig. 16). Sjogren says that the last rise of the Caspian left marls and clays 50 or 55 meters o\'er the present water level. On the most exposed headland that we visited, about 6 miles northeast of Baku and 160 feet above the sea, blocks of sandstone, 5 or 10 feet in size, were detached from their ledges and left standing in disorderly attitudes, which seemed less the result of ordinar)- pro- Fig. 1 6. — An old Caspian Shoreline, near Baku. cesses of weathering than of former seashore forces. There are also occasional mounds or delta-like deposits of fine silt in protected re-entrants of fonner shorelines as at A, fig. 15, at altitudes similar to those of the cobble benches ; but these features are so discontinuous that it was not possible to correlate them safely. Their discon- tinuity does not appear to be due to subsequent erosion, for none of the shore records seem to have suffered significant change, except one of the silt deposits that lies in a ravine, and that has been channeled by its wet-weather stream. This silt deposit (A', fig. 15) is just west of Bibi-Eibat and contains land shells in its upper part, but its fonn and jx)sition are such as to indicate the deposition of its greater volume as a delta. It lies on a bed of well-rounded cobbles and bowlders, exposed CASPIAN SHORELINES NEAR BAKU. 31 in the ravine, and thus shows that the high-water stand when the silt was deposited liad been preceded by a time of less high water. A few miles east of Baku, a flat hill-top (B, fig. 17) was sparsely strewn with water-worn cobbles at a height of 430 feet ; and here we found a well-formed pothole, about 3 feet in diameter, and of somewhat less depth, with a c round stone hing in it. South- west of Baku, near the southern end of the monoclinal ridge be- yond the oil-wells of Bibi-Eibat, a small patch of cemented cob- bles, pebbles, and broken shells lay at a height of about 460 feet; but it may be that this is simply a remnant of a Pliocene deposit. The most interesting records of the modern high-level Caspian near Baku were found in three cobble spits at about 600 feet altitude above the present water level. As no accounts of the Baku district that I hav'e read make mention of shore records Fig. 17. -Three-mile section of Ridge, six miles northeast of Baku, looking north. Fig. 18. —The Oil-Wells of Bibi-Elibat, two miles south of Baku, looking south. at SO great an altitude, these spits will be described in some detail. The first one was found at S, fig. 15, on the top of the horseshoe ridge of the late Tertiary Aralo- Caspian (Pontic) .sandstones that incloses the anticlinal valley of the Bibi-Eibat oil- wells. The spit was somewhat east of the apex of the ridge cur\e. The anticline is figured in section in the little handbook, "Guide VII des Excursions du VII 32 EXPLORATIONS IN TURKESTAN. Congres international geologique," and the section is reproduced by Mushketof (1899, I, 304). Tlie ridge may be reached by going ni>hill, southwest from Baku, past a church and cemeter*' on a gravel-covered ])ench that o\-erlooks the cit)- at a height of about 330 feet. A quarn,- on this bench shows the late Tertian,- strata, with abundant shells. The view from the ridge over the Bibi-Eibat valley with its oil-wells and the Caspian beyond (fig. 18) is a repaying one. The spit is 250 feet wide at its proximal end, 20 or 25 feet thick, and 1,300 feet long; it trends N. 20° W. (magnetic) for most of its length, but turns N. 70° E. near its end. It descends gradually, so that the northern or free end is 50 feet lower than the southern or attached end. Its eastern or seaward side slopes about 5° ; its western or landward side slopes 18°. A number of pits tliat have been dug in its western Fig.. 19. — A Cobble Spit on a ridge near Zuyk. seven miles northeast of Baku, looking north; fissured Aralo-Caspian Strata in the foreground. side show that it is made in great part of small pebbles that seem to ha\'e been derived from the somewhat pebbly sandstone of the horseshoe ridge; but it also contains rounded sandstone and conglomerate cobbles and bowlders up to 3 or 4 feet in diameter. The anomalous feature here is the absence of corresponding marks of shore action on the slopes of the higher ground to the southwest, where the hill-tops are nearly 300 feet higher than the ridge on which the spit is fonned. Furthermore, on crossing the barren monoclinal \-alley of the \'assaniala (which is followed by the railroad to Tiflis, a few miles west of Baku, fig. 15), to the anticlinal hills of petroleum-bearing strata, whose summits reach about 1,000 feet altitude, we were unable to find any well-defined shore marks corresponding to the level of the long spit The highest safe record here was a bed of cobbles at 200 feet altitude. CASPIAN SHORELINES NEAR KRASNOVODSK. 33 We were therefore disposed to doubt the existence of a 600-foot shoreline until further search on the hills east of Baku, in a much more exposed situation than that of the anticlinal hills to the west, discovered other cobble spits on the west slope of the north-south monoclinal ridge of west-dipping Aralo-Caspian (Pontic) calcareous sandstones over the little village of Zuyk, at essentially the same altitude as the long spit on the Bibi-Eibat ridge. The position of these spits is shown at C, in fig. 17, and the profile of one of them in fig. 19. It should be remarked that they are on the western side of the ridge, and therefore turned away from the open Caspian. They are about 600 feet apart. Each one has the form of a flat spur, a little lower than the crest of the ridge, about 160 feet wide and 250 feet long, falling off with a steep western face of 1 5 feet on the free western side. They are composed, as far as may be judged from tlieir surface materials, of rock slabs, from 2 to 4 feet in diame- ter, and of rounded cobbles, derived from the ridge ; also of pebbles, worn from the ridge-making pebbly sandstone. Close by the southern spit is a small patch of cobbles, lying on the bare rock of the ridge slope; 1,000 feet further south is a larger oval patch, 250 feet in diameter and 8 or 10 feet thick, of cobbles up to 2 feet in diameter. Although the inner structtire of these spits and patches was not revealed, we were constrained b>- the significance of their materials, fonn, and position to interpret them as the mark of a fonner Caspian shore, when the crest of the mono- clinal ridge appeared only as a low island, exposed to the full force of deep-water wa\-es, by which the slabs were toni from the exposed eastern face of the island and thrown on its western side. As in the case of the cobble spit on the Bibi-Eibat ridge, these spits nuist ha\-e been rapidh' formed during a relatively brief high-le\-el stand of the Caspian. In an\- case, a special importance attaches to the highest shoreline, and it was therefore with no small degree of interest that we looked forward from our stay at Baku to the opportunity of studying the eastern coast of the Caspian at Krasnovodsk. THE QUATERXARV SHORELINES NEAR KRASNOVODSK AND JEBEL Krasnovodsk is on the north side of a bay that is inclosed from the Caspian by a long soutli-pointing sand-spit. Here we were courteously received by Colonel \'olkofnikof, governor of the district, who detailed one of his mounted guards to ser\'e as a guide. An afternoon and a morning gave us time to measure a number of elevated beaches and to find some high-lying cobble beds of doubtful relations. The barrenness of the landscape was remarkable, in view of its innnediate proximity to the sea, whose waters stretch beyond the horizon to the south and west. The town stands in part on the eastern slope of a "tombolo" or gravel reef, which, with a similar but higher reef a mile or more to the west, has tied a fonner island of granitic rock to the limestone escarpment of the mainland on the north, as shown in fig. 20. The eastern reef is about 135 feet over the Caspian ; the western reef, more exposed to the sea waves at its time of making, reaches a height of 185 feet. A ditch that had been cut through the eastern reef disclosed something of its structure, from which we inferred that it was built during a time of rising water. 34 EXPLORATIONS IN TURKESTAN. Beaches and cobble beds in the same neighborhood were noted at 8, 20, 35, 45, 60, 1 15, 135, and 210 feet. The precipitous southern escarpment of the barren Kuba Dai,'-h, which stretches east and west, a mile north of Krasnovodsk, has a steeper slope and a lighter color near its base than above, because of the subrecent under- cutting h\ the high-le\-el Caspian waves and the resulting exposure of un.weathered rock ; this suggests a verj- recent high-water stand of the sea. The elexated beaches that extend from the eastern tombolo along the mountain Ijase are skirted by the railroad for some miles. Many sections of their rolled gravels are exposed. All these reef and beach deposits are so laid as to sho\\- that previous to their forma- tion the surface on which the)- rest had been subject to subaerial erosion. Hence here, as at Baku, the Caspian rose to its fonner levels, yet whether from a lower level than to-day I can not affirm ; but Walther quotes the record of a boring on the shore of the Caspian southeast of Krasnovodsk in which "dune .sands" were found Fig. 20. — Rough Sketch Map and Secrions of the District about Krasnovodsk. to a depth of 35 meters (1898 ,2 1 1). The volume of material in these reefs and beaches, on the lee shore of the Caspian, was much greater than in those about Baku, and the beaches were comparable in size to the beaches on the ele\ated shorelines of the Bonneville and Laurentian lakes. The size of the spit that incloses the bay of Krasnovodsk at present sea level is also much larger than an}- wave-built sliore fonns that we had seen near Baku. Shorelines of similar altitude were seen on the flanks of the Balkhan Moun- tains, near Jebel station of the Central Asiatic railroad, about 100 miles east of Krasnovodsk. The station was 56 feet over the Caspian, and from this we detennined the neighboring delta beaches, a mile or two distant, to be 150 and 250 feet over the same base. One of the higher deltas is shown in fig. 21. There was nothing indicative of shore-wave work seen at still higher levels on the mountain side. It was to deposits of the Pliocene Caspian that Konshin (1886, 383) refers in a neighboring locality as giving unmistakable traces of seashore action at a height of almost "50 sazhen" (roughly 300 feet) over the present Caspian. Walther makes brief reference to the deltas near Jebel (p. 103). It is to be noted that the delta beaches of the two le\-els here recorded occur in the lower part of ra\-ines eroded in the northwest face of the mountain, and show that here as elsewhere CASPIAN SHORELINES NEAR KRASNOVODSK. 35 the processes of erosion had had a lower baselevel before the beaches were built ; that is, the Caspian here as elsewhere rose upon the mountain flanks from a fonnerly lower level. The more problematic cobble deposits near Krasnovodsk lie at altitudes of from 400 to 470 feet over the Caspian, in notches (NN, fig. 20) on the steep southern face of the high escarpment, the Kuba Dagh, fonned of vertical Jurassic limestones, whose sharp points rise 600 or 1,000 feet abo\'e the sea. There can be little doubt that the well-rounded cobbles and bowlders, from 2 to 5 feet in diameter, indicate wave action, but it is not clear when the wave action took place. A curious feature is the occurrence with the cobbles of subangular scraps of dark crystalline rock, up to 5 or 6 inches in diameter, apparenth- derived from the cnstalline ridge at the Fig. 2 1 . — An Elevated Caspian Shoreline in the Balkhan Mountains, near Jebel Station, Central Asiatic Railway. end of the tombolos, although a mile of low land now separates the ridge from tlie Kuba Dagh. It is eminenth' possible that the cobbles should be associated with the horizontal marls and limestones, Andrussow's " Aktschlag\lscliichten," a section of which we saw on the caravan route to Klii\a on the north side of the Kuba Dagh, micoinformably overlying its vertical layers, as in fig. 20; and if so, they would be iiuich older than the modern Caspian shorelines that we were looking for. The only safe test to apply to these cobble beds, as well as to those in the 600- foot spits near Baku, will be to search for them at other points where the coast is high enough to have received similar marks. If we provisionally accept the Baku spits as marking a temporaiy shoreline, it is possible that much of their exceptional height may be due to relativeh^ local warping. Such a supposition is not inherently 36 EXPLORATIONS IN TURKESTAN. improbable, for Baku lies on the line of the Caucasus range, where great disturb- ances have taken place in not remote geological periods, and where minor movements might exjDectably be continued into recent time. It should be noted, moreover, that the highest shorelines at Krasnovodsk, 210 feet, and at Jebel, 250 feet, differ by a greater amount than should be ascribed to error of barometer readings, and that both of these levels are decidedly below the undoubtable signs of modem wave work near Baku, at 400 feet In further confirmation of warping, we may quote Mushketofs statement (1886, I, 692) to the effect that in the southern Caspian the Quaternary Aralo-Caspian shoreline almost merges with the present shoreline. In \-iew of this it is desirable to measure the elevated shorelines of the Caspian at many points before attempting to restore its outline at the time of its maximum extension. It is very possible that the relative dates of the various shorelines may finally be better detennined by means of the amount of warping that the\- have suffered — the latest ones the least — than in any other way. Further consideration of the eastern extension of the Caspian will be found in subsequent pages. THE PLAINS OF SOUTHERN TURKESTAN. A great part of Turkestan, south and east of the Aral Sea, is a desert plain connecting southwestward with the lowland bordering the southern Caspian by the Balkhan gateway in the belt of highlands that, farther to the southeast, fonns the boundar\- of the Russian and Persian dominions. A large part of the desert plain is described by some of the Russian geologists as having been covered by the Pliocene Aralo-Caspian Sea, and a smaller southwestern part by the post-Pliocene sea, whose waters have since then gradually withdrawn to their present separate basins. It is evident that the varying area of this great inland sea must have, directly and indirectly, exerted a controlling influence on the distribution of the contemporan,- human hihabitants of the region, if any such there were ; hence the importance of gaining as full a knowledge as possible of Aralo-Caspian histon,' in the course of our explorations. The following summary' concerning the relation of the southern Turkestan plains to the Aralo-Caspian problem, as detennined by Russian observers, ma\- ser\-e as an introduction to the record of our own obser\ations. One has frequent occa- sion, in reviewing the reports of the Russian explorers, to admire the persistence with which the>- penetrated the desert region, and to percei\-e in their successful subjugation of this part of the Asiatic wilderness a close similarity to our " winning of the west," except that theirs is the greater task ; for the deserts of Asia are broader and more barren than those of North America, and the mountain ranges are higher there than here. The settlers of the United States had a continent of moderate width to cross and found within it only a scattered native population, and on its Pacific side only a slightly resistant offshoot of Spanish power, while the Russians are expanding into the broadest of the land masses, where the people of the interior are well established, where the British occupation of the populous peninsula of India is more aggressive than the Spanish occupation of Mexico, and where the enonnous populations of the Pacific border find no American analogy. THE ARALO-CASPIAN SEA IN THE KARA-KUM. 37 The plains of southern Turkestan are described by Mushketof and others as occupjing an extensive area of depression which has received the waste washed into it from the surrounding higher lands. These higher lands are as follows : The Ust-urt plateau on the west is an uplift of late Tertiary- strata, being covered in its western part at least by the Akchlag\l formation of Andrussof (1902). Krasno\-odsk lies southwest of this upland, and the sections already given in fig. 20, as well as the escarpment of the Ust-urt farther east, suggests that the upland is bordered by a fault along its southern and southeastern margin. The Kopet Dagh, on the south, has been described by Bogdanovich (1887). The range is largely composed of Mesozoic and Tertian.- limestones, folded in a .somewhat orderly fashion, with axes trending west-northwest. The northwestern part of this line of disturbance is known as the Kurian Dagh, the Small and Great Balkhans, and the Kuba Dagh (the last rising back of Krasnovodsk). The farther extension of the same line leads to the Caucasus range. The plains are bounded on the east by the out-reaching members of the great mountain systems of Central Asia, well known to in\-ol\e late Tertiar>' and post-Tertiar)- uplifts, as will further appear in Mr. Huntington's report. To the north the plains continue far beyond the region here considered. The depressed area between these higher lands, the southern Turkestan depres- sion, is called a grnbcn by Mushketof, at least that part between the I'st-urt and the Kopet Dagh. It seems to have been kept below the surrounding highlands b}- repeated differential mo\ements, and it has therefore long been receiving their waste. It slopes away from the higher borders after the fashion of piedmont fluviatile plains, of which it seems to be in large part an excellent example. Its surface materials are coarse near the margin, but become finer farther forward. Many of the streams that descend from the mountains wither away on the plains; only the largest rivers, the Amu and the Syr, succeed in reaching the Aral. The Tejen and the Murg-ab disappear on the southern plains ; the Zerafshan, greatly reduced by use in irriga- tion in Bokhara, approaches but fails to reach the Amu ; and the Clui wastes away on the plains farther north. It is the district south of the Amu with which we are at present concerned. This part of the plains is chiefly a barren waste, the Desert of the Black Sands, the Kara-Kum. THE QUATERNARY ARALO-CASPIAN IX THE KARA-KUM. The deposits of the Pliocene Aralo-Caspian are described by some WTiters as underlying all the Kara-Kum, but there does not seem to be entire agreement on this point. The Ouaternar].- Aralo-Caspian is belie\ed to have been of less extent, but it has not been well defined in Turkestan (cf Mushketof, 1886, I, 696), probably because of the difficulty of exploration in the desert. Jakalof (1882) speaks of the general belief that the Kara-Kum is the bed of the expanded Aralo-Caspian Sea, but notes that sea shells are not found in the desert. Sjogren (1S8S) briefly states that the last rise of the Caspian covered the Kara-Kum. Konshin ( 1 896) gives a sketch-map of the sea, showing its area at the beginning and at the middle of the Quatemar}- period and at the opening of the present or historic period, and thus ^o )4 6 38 EXPLORATIONS IN TURKESTAN. indicating a progressive diniinntion of size. A continuous decrease from the larger Pliocene to the diminishing Quaternar>- area is inferred by this observer and explained by dr}-ing winds and by uplift of the eastern part of the plain, where the surface is now 2,000 feet above sea-level. Obruchcf also describes the Quateniar)- Aralo-Caspian as the direct successor of the Pliocene sea, the decrease of area being ascribed to uplift on the east (1890, 25). Neither of these obser\-ers gives explicit recognition to the idea that the Quaternar)- sea resulted from the expansion of a smaller early-Quaternar}- sea, to which the waters had shrunk from their great Pliocene extension. The Aralo-Caspian is marked by Konshin, in the article just refened to, as reaching, at the beginning of the Quaternar)-, eastward to the present ends of the Murg-ab and Tejen rivers, and southward to the base of the mountains at Kizil- Arvat ; farther west it connected with the Caspian basin by the Balkhan gateway ; to the northwest it spread be)-ond the present Aral ; to the northeast it had a well-defined boundar)' south of the Anui River. Here a higher northeastern part of the Kara-Kum, underlaid by Pliocene and older strata, breaks off in a dissected, south-facing escarpment, the Ungus, which Obruchef ascribes to a fault (1890, 250), and along the base of which Konshin describes shorelines (1887, 238), probably contemporaneous with those at Krasnovodsk and Jebel. The floor of the depression south of the Ungus is stated by Lessar to be 44.6 meters below the Caspian (1889, 7 14). This escarpment and the shorelines along its base are features toward which future obser\'ation might well be directed, with the hope of deciphering the histoiT of the sea in greater detail. If I understand Konshin's description, the dissection of the Pliocene strata in the escarpment must have taken place before the shorelines were made at its base. It might, therefore, here be possible to recognize the time interval that obsen'ations elsewhere lead us to suppose elapsed between extensions of the Pliocene and the Quaternar}- Aralo-Caspian Sea, and perhaps to decipher the pre- sumably complicated histor}- of the Quaternary- sea itself In the late Quaternary-, the sea was reduced to lower and lower levels, and the Caspian and the Aral were thus separated, except for a water passage or channel, the Usboi, which passes along the southeastern base of the Ust-xnt and through the Balkhan gateway. There has been much discussion regarding the nature and origin of this channel. As it has the form of a river channel, and as the Anui is the only large ri\-er in the region, the Usboi has been repeatedly said to be the former course of the Amu. For example, Sievers (1873) describes the Usboi as a channel so well preser\'ed that it seems to have been only lately abandoned ; it is about 65 feet deep, two-thirds of a mile wide, eroded in the unconsolidated deposits of the steppe or in the firmer Miocene beds on the border of the Ust-urt. The channel has man}- bends ; it often divides, .so as to include islands, but there are no branch channels entering it. Other obsers-ers have noted that the gentle southwestward descent of the channel is broken by the sills of rapids at several points, from wliich it may be inferred that the stream by which the channel was eroded did not endure long. The Amu being a large river not far distant, its former connection with the Usboi seems to ha\-e been assumed without waiting to trace an actual connection between THE USBOI CHANNEL. 39 the two. So, in 1881, wlicii Koiisliiii first saw the Usboi, he also took it for the old path of the Amu (18S6, 380), l)ut on further examination he concluded that while the depression in which the Usboi is eroded had served as a strait to unite the expanded Aral and Caspian seas, it had never sen-ed as the path of o\-erflow from the Aral to the Caspian, and that the river-like channel along the axis of the depression was the work of local wet-weather streams (1886, 427-431) ; but it should be noted that one reason for this conclusion was the deductive belief that the Aral could not have had a water supply sufficient for overflow after the climate had become so dv}- as to cause the Caspian to shrink below the Aral level (1886, 428). Some ten years later (1895) Konshin reversed this earlier opinion, and treated the Usboi as the channel carv-ed by the Aral overflow outlet. He still maintained, however, that the Amu had never flowed directly into the Usboi, and in evidence of this he pointed out that there was no channel leading from the Amu to the head of the Usboi ; that the Sary-Kamish depression lay between the two, and that the Usboi channel was decided!}- smaller than that of the Amu to-da)-. More than one writer notes the absence of canals and ruins along the Usboi, and concludes that the river which eroded the channel must therefore have been salt and unattracti\'e to settlement. This conclusion mifortunately begs the important question of the existence of a house-building and canal-cutting human population at the time the Usboi was formed. No independent proof of man's existence at that time and in that place has yet been found. In this connection the levels at some critical points may be introduced. Bala Isliem, 336 feet (72 meters) above the Caspian, is at the divide between the Aral and the Caspian districts ; the Usboi is eroded on the gentle slope southwest from the divide ; no channel occurs on the northeast slope. Sary-Kamish is the name of some .salt lakes in the bottom of a depression north of Bala Ishem, 50 feet (15 meters) below the Caspian, whose separation from tiie Aral of to-day may be due to the growth of the great Amu delta between the two basins. Walther quotes various other altitudes (1898,212). As the Amu now enters the Aral alone, the fonner waters of the Sary-Kamish depression have been e%-aporated almost to dryness, thus repeating the case of the Colorado River at the head of the Cnilf of California. The I'sboi channel nuist have lengthened southwestward as the Caspian retreated, thus producing features similar to those well known in the Bonneville basin of Utah. It is pertinent to quote in this connection Semenofs obser\-ation that the plain bordering the Caspian southeast of Krasno\odsk appears to be the remains of spacious deltas fonned by large rivers which for man}- centiiries here entered the sea from the east (1888, 292). Konshin (1887, 237) notes that Caspian shells are abundant on the desert plain for 125 miles (200 km.) east of the present shore and up to nearl}- 200 feet (60 meters) above the present level; but the}- are not mentioned in association with the .shorelines of the Ungus. Obmchef gives similar statements (1890, 246). Tliere seems to have been comparatively little discussion of the relation of the Quaternary Aralo-Caspian in Turkestan to the climatic changes of the glacial period. .Sjogren (1888) cxjilains the ex]>ansion of the sea b\- the greater volume of water received from the glaciated area of northern Russia, and suggests that as far as 40 EXPLORATIONS IN TURKESTAN. the Aralo-Caspian region is concerned, the expansion of the sea was the cause rather than the consequence of local climatic changes. Petrusevitch (1880) ascribes the shrinkage of the sea and the withering of the Murg-ab and the Tejen from an inferred connection with the Amu, to an assinned destruction of forests in the neighboring mountains. The probability of repeated Quate^lar^• expansions of the sea does not appear to have been considered ; but in this statement I may be doing injustice to Russian obser\'ers, whose more recent articles I have not been able to consult. THE PIEDMONT PLAINS. Since the withdrawal of the Pliocene sea, the eastern and southern borders of the plains of southern Turkestan appear to ha\'e been aggraded by the rivers that flow out upon them from the mountains. That a certain measure of such constnic- tive action has taken place is announced by the Russian geologists, but it is not apparent that tlie full measure of ri\er action has been recognized. Some of the strata of the plains are .said to be not fluviatile but lacustrine, because they are of fine texture and uniform structure, without the variable layers of gravel that are by implication supposed to be always indicati\'e of river work ; but this seems to be a simpler solution than the problem deserves. There are man}' rivers that do not carr\- gravel, and there are many river plains whose smooth surface nuist receive ver)" even and unifonn deposits of flood-laid silts o\'er large areas. Records of borings are quoted by Walther (1888, 210) which show river nuids on sand and loess to a depth of nearly 50 meters beneath the bed of the Amu River at Charjui, where the great railroad bridge was built. The record of a well boring at Askhabad, quoted by the same author (1900, 105) shows variable piedmont deposits over 2,000 feet deep. It seems, indeed, as if we had in the plains of Turkestan and the Great Plains of our West one of the most striking of the many physiographic resemblances between Eurasia and North America ; and that there as well as here an increasing share may be given to the action of aggrading rivers in fonning the plains, as obseiA-ations are extended. It is well known that the tide of geological opinion in this countr\' has in recent years tunied more and more toward a fluviatile origin for the strata of the Great Plains that slope eastward from the Rocky Mountains, and the traditional lacustrine origin of the plains strata has been repeatedly questioned; so we may e.xpect, as closer attention is given to the details of river-laid fonnations, that a larger and larger share of the fresh-water strata that slope westward from the mountains of Central Asia may be interpreted as fluviatile rather than as lacustrine. In one respect, however, the comparison between the two continents reveals a contrast. In North .\merica the rivers that flow eastward from the Rocky Moun- tains are now dissecting the plains that they once built up, as has been so well shoxsTi by Johnson ; while in Turkestan the rivers that emerge from the mountains, heavily silt-laden, are still engaged in building up the plains. This is notably the case with the Murg-ab and the Tejen, as will be more full\- stated below, for these rivers wither away without reaching the sea, and ever>- particle of sand and silt that they bring from their headwater valleys in the moimtains must be laid down as the}- dwindle to dryness on the plains. Moreover, while the rivers at present bring abundant gravels out from the mountains and spread them on the nearer parts of THE AKHAL-TEKIN OASES. 41 the plains, the ri\ers of late Tertiar>' time must have had a much smaller quantity' of coarse detritus ; for, at that epoch, the mountains had been reduced to relatively low relief, as will be shown particularly in Mr. Huntington's report, and the waste that they then shed must have been for the most part of fine te.xture. It appears, therefore, that a ver}' careful examination of the fresh-water Tertiary- and Quaternary .strata in the plains of Turkestan should be made with a view of deter- mining not only the date, but also the physical conditions of their deposition. It is evident that the opportunity for organic life, and especially for human life, would have been very different, according as the plains are of lacustrine or flu\iatile origin. Inasmuch as man}- mounds and ruins occur within the area of debatable action, the solution of this problem has a close relation to the objects of our expedition. THE .\KHAL-TEKIX OASES. The gently sloping plain that lies piedmont to the Kopet Dagh and the asso- ciated ranges — the mountains that divide Persia and Turkestan — is a case in point The plain here receives from point to point sufficient water from the mountains to support a series of \-illages, known as the Akhal-tekin oases. The Central Asiatic railroad, from Krasno\-odsk to Tashkent, naturally was constructed through this settled belt on the way into the interior. A section of the mountains at Kizil Ar\-at is given by Bogdanovitch (1887), in which the north-dipping ^Miocene limestones and clays on the crests and flanks are followed b)- the horizontal layers of the plains, which are labeled Aralo-Caspian. Again, Konshin's sketch map (1896) of the Quaternary- sea brings its border close to the mountain base at Kizil-Ar\-at. He had earlier (1883, 383) reported the occurrence of variegated clays in the gorges back of Kizil- Ar\-at, which he referred to the Pliocene Aralo-Caspian. During our brief stop at Kizil- Ars-at we rode out to the mountains and had a good view of their structure. The mountain-making rocks are hea\-y- limestones, underlaid and overlaid with clays or shales, all compressed into great folds, and much denuded. We looked from one of the anticlinal limestone ridges into an inner syn- clinal valley, where the weak clays that overlie the limestones were terraced. Tlie stream from this inner \alley cuts a narrow gorge near the end of the west-pitching limestone anticline, but the road follows a valley around the west end of the anti- cline. Where the stream issues from the mountains it has terraced the reddish and yellowish clays on the northern slope at several levels, and has strewn gravels on the terrace floors. The terraces decrease in height northward, as if they would merge in the plain, but the front of the higher terrace has been much consumed and eroded into a sort of bad-land topography-, shown in fig. 22, during the produc- tion of the lower terraces. This suggests a recent uplift, with its greatest measure in the range and rapidly decreasing toward the plains. The spurs of the mountain ridges hereabout seem to ha^•e been graded to moderate slopes with reference to the uppennost terrace, while narrow ravines and gulches are cut in the mountain flanks with respect to the present valley floors. Evidently- a much longer time must have been de\-oted to the erosion of the highest terrace floor, which once extended continuously along the mountain base, than in opening the 42 EXPLORATIONS IN TURKESTAN. narrow valley floor of the present stream. Evidence of similar terracing in the range southwest of Askhabad will be given in a later section. We saw no indica- tions of deltas or other shoreline features here — nothing but the results of forward- washing stream action. It may be that the chief evidence for drawing the Quater- nar>- Caspian shoreline near Kizil-.\r\at is to be found in the agreement of the altitude of the plain, a few miles from the mountain base, with the level of the sea as detennined b>- recognizable shorelines elsewhere. In that case its location can, of course, be onh- approximate. At Bakharden, between Kizil-Ar\-at and Askhabad, we rode out to the dunes along the course of a small stream, \\hose occasional floods keej) a graded jiassage open among the sands for several miles from the mountains. The surface of the led Terraces at (he base of the Kopet Dagh, south of the Kizil-Arvat, looking southwest. The horizontal Hmestones o( the Mountain on the lef Fig. 11. Dlssec I the Terraces in the middle distance left are suddenly bent down so as to pass under the clays of sands was irregular at first (fig. 23); then the dunes began in moderate relief, seldom exceeding 15 feet in height. The scarps of the crescentic dunes or barkhans (fig. 24) were to the west, as if the sands had been drifted by easterh- winds. The sand bore a scanty growth of grass, except on the freshest dunes. Between the dunes and the mountains there was no sign of shore-terrace or delta observed. The piedmont slope extends forward without interruption as far as we saw it. It should, of course, be remembered that the abandoned Caspian shorelines, wherever they stand on the piedmont plain, may be faint and not easily recognizable ; nevertheless, they were recognized so easily at Baku, Krasnovodsk, and Jebel, that failure to see THE AKHAL-TEKIN OASES. 43 them at Bakharden and elsewhere along the base of the Kopet Dagh inaj- be fairly taken to indicate tliat the\' do not exist there. The little deltas in the ravines on the nionntain flank near Jebel were recognized at the first glance, though a mile or more awa}- ; the strands at Krasnovodsk were visible as such from the steamer before reaching land. The treeless piedmont plain on which the Akhal-tekin oases are distributed is open, as .soon as one leaves the villages, without obstruction to the view for miles together, and yet shows nothing that coidd be interjjreted as a shoreline. It may l)e noted that familiarit}- with the Bonneville shorelines in Utah gave us all the more confidence in the correctness of our conclusion that no shore- lines occur along the base of the Kopet Dagh at Kizil-Arvat and farther eastward. Fig. 1}. — Sand-hills near Bakharden. looking south. The railroad journey through the belt of oases afforded excellent op]')ortunity for many general views of tlie piedmont slope. Gorges in the barren mountains ojDen upon fans, whose long forward descent was well seen in profile before or after passing them. The}' had no resemblance to the flat-topped deltas built in the high-level Bon- neville waters along the base of the Wasatch Mountains in Utah. In a district where the limited water supply liardly suffices for the needs of even a scanty population, and where the unredeemed desert counts more area in miles than the fields rescued from it count in acres, it was curious to note the precautions taken to guard the railroad from destruction by floods. The faintly convex surface of the fans sheds the floods now on one radius, now on another; the point where a flood will reach the track 44 EXPLORATIONS IN TURKESTAN. can not be foretold. Embankments or dikes are therefore thrown np in oblique lines on the ii])-slope from the track, so as to gfiiide the floods toward strong cuh'erts under the roadbed. Yet even these safeguards do not alwajs suffice. Not long after we left this part of the country the news o\-ertook us of a destmcti\'e flood b\' which a jxirt of the track near Kizil-Arvat had been washed away. The irregular structure of the piedmont slope, as exposed in cuts along the railroad line, is well described by Walther (1900, 104). There is a frequent and irregular alteration of stratified or massive loess-like clay, finely stratified sands, and coarse gravel, with many local unconfonuities ; all this being the result of the variable action of floods that sweep suddenly, unguided by channels, down the Fig. 24. — A Barkhan near Bakharden, looking south. piedmont slope ; now eroding, now depositing ; here sweeping along coarse blocks, there depositing fine silts. Ten miles south of Askhabad, where the railroad station is 819 feet altitude, we saw, when returning by the Meshed road from an excursion in the Kopet Dagh, more abundant piedmont deposits of moinitain-waste dissected to depths of several hundred feet. A great thickness of these deposits has been penetrated by the artesian boring in the suburbs of Askhabad, already mentioned, 2,000 feet deep, and therefore with more than half its depth below sea level, but without securing a water supply. The whole depth, as shown in the record quoted by Walther (1900, 105), is in variable layers of clay, .sand, and gravel, similar to the deposits seen in the borrow-pits near the railroad embankments, or in the natural THE AKHAL-TEKIN OASES. 45 sections; and all of this heavy deposit is therefore best explained by conditions and processes like those of to-day during^ persistent depression of the surface. The failure to secure a water supply from this deep well is in itself vor>- suggestive of the irregular underground structures and of their torrential origin. Among the most interesting features of this region are the gently ascending tunnels that are driven in search of water into the gravels of the piedmont slope, near the mountain base. Streams of sufficient size to use in irrigation are thus led forth. The practice is au ancient one, and is in use from Turkestan to India. It has lately been introduced, with good results, in the arid parts of southern California, where piedmont fans of mountain-waste are extensiveh- developed. We were told Fig. 23. — A Village of Turkoman Kibitlcas, near Kizil-Arvat. at Askhabad that trouble frequently arises between neighboring villages when the excavation of a new tunnel causes a lessening of the water suppl}- from an older tunnel. The native \-illages (fig. 25) seemed wretchedly poor at first sight, )-et some of the circular tents — kibitka.s — are well furnished on the scale by which the people there measure the needs of life; and the carpets and wall-bags are wo\en — one should rather say crocheted — with a remarkable degree of taste in design and color, and of skill in memorized execution. W'e were entertained one afternoon near Askhabad bv the head man of the native village, who had been with us on an excursion. Rugs were spread in his little orchard, tea and fruit were ser\-ed, and native music was provided. 46 EXPLORATIONS IN TURKESTAN. THE KOPET DAGH. Our intention in making an excnrsion fioni Askhabad into the Kopet Dagli range was to make fnrther search for any geologic or physiographic featnres in the mountains which miglit suggest subdivisions of recent geological time, the correla- tives of which could then perhaps be recognized in the more monotonous structure of the piedmont plain. We were fairly successful as far as the mountains were concerned, for indications of subrecent terracing were found in tlie valle\s here even more distincth- than back of Kizil-Arvat, but the recognition of the effects of the V7. ai9' fl A.SKABAD •^Arl,•^ian Well. Markou 5058' %P'-, steep-dipping limestones. This range is believed to be faulted iip along its front, because the strata in the neighborhood of the gorge either dip southwest into the range or lie nearly horizontal. The scarp of the range, much ravined, looks directly upon the open plains. General subaerial erosion can not have removed the forward extension of the strata to any great extent, for erosion has as yet only succeeded in battering back somewhat the steep walls of the o-orge ; hence the absence of the strata in front of the range can only be explained by faulting. It should be noted that we caught a glimpse, while we were still on the plains, of what .seemed to be steep northea.st dips in the strata of the front scarp a few miles northwest of the gorge ; hence the faulted monocline may there assmne the character of a toin anticline. The treeless hills of the Firuza syncline revealed their structure most clearly. The dip of the .strata was distinctly steeper on the northeast than on the southwest side ; the lower beds were grav .shales, on which subsequent vallejs were opened ; the upper ones brownish sandstones, which rose in ridges. The total thickness was probabl)' i , 500 or 2,000 feet. The limestone flanks of the main range exhibited many smooth stnictural slopes of moderate dip, green with vegetation, and deeply gashed by con.sequent streams. The upper Firuza gorge was seen as a deep chasm, which we followed through the next day. Its stream was only 10 or 15 feet wide, but about a month after our visit we heard that it rose in a destructive flood and swept through the village, doing much damage to the houses and gardens. The upper gorge is as fine an example of a transverse through-going defile as I have seen. It is 10 miles long, and in that distance the valley floor rises about 2,500 feet. For the first half of the way there is a narrow flood plain between pre- cipitous walls, hundreds of feet in height ; then after passing a strong fault, expressed by local defonnation and a change in the character of the limestones, the walls are less steep and the floor is more encroached upon b}- talus and fans. The mountain tops, 4,000 or 5,000 feet above the stream, could not be seen. As the wagon road ended at Firuza, our further progress was on horseback with pack train, and thus we crossed the boundary into Persia. We met a few men in the gorge driving donkeys laden with fagots, but came upon no habitations till we reached the open longitudinal consequent valle>- where the little Persian ^•illage of Serani is situated amid green irrigated fields, at an altitude of about 4,700 feet. The irri- gating stream is chiefly supplied from a large spring at the base of the limestone range on the soiithwest side of the valley. The stream is used to drive a primitive mill near its source. THE KOPET DAGH. 49 THE SERANI VALLEY. The Serani Valley is worn down on the gray shales of a pinched and torn syncline, between the broad limestone anticline of the main range on the northeast and the torn or fanlted anticline of the Bnuzan range (8,922 feet) on the sonthwest. The shales are largely removed and the limestone flanks of the valley are shaqjly ravined near the exit gorge ; bnt a few miles to the northwest we saw the terraced remnants of a higher valle>- floor (fig. 27), estimated to be 600 or 800 feet over the present stream. It was noted that the limestone flanks of the mountains sloped by relati\-eh- gentle and somewhat graded decli\-ity to these terraces, and that the flanks descended b\- much steeper and more ragged walls to the floor of the new valley near the outlet gorge, where the terraces had been largely removed. When the high terraces of the Serani \'alley are considered in con- nection with the lower ones alread}' described at Firuza and at the mouth of the lower gorge, a differ- ential uplift of the region is sug- gested. Such an uplift of the Serani Valley with respect to the moinitain front would not be measured simply by the height of the \'alle}- terraces. Fig. 27. — Terraces in ihe Serani Valley, looking northwest. Under the supposition of ui)lift, the slope of the stream in the gorge must ha\-e been much more gradual when it connected the now dissected floors of the earlier Serani and Firuza valleys than it is to-da}- ; for the earlier valley floor must have approached maturity, as is shown by its greater width in the Firuza syncline and by the more nearh* graded slopes of the limestone mountains over the Serani terraces, while the present valley is relatively inunature, as is shown by its narrowness in the shales of the Firuza syncline and by its abru])t walls and its land-slides near Serani ; and it is well known that mature valleys in a mountainous district must have a much more gradual slope than immature valleys. It is therefore reasonable to estimate the inferred recent axial uplift of the range at 1,000 feet at least; indeed, 2,000 feet does not seem to me an excessive measure. On following the Serani Valley to the southeast on the morning of June i, we soon passed two large landslides (see fig. 26). The second one was a good mile in length, with irregular mounds and hollows strewn with huge limestone blocks. The slides seemed to ha\e come from the main range and to have been precipitated by the revival of valley erosion, whereby the basset edges of the limestones on the torn slope of the anticline were undennined. Beyond the slides the valley floor was aggraded for a mile or more, and the stream was here lost in its own deposits. At about 6 miles from Serani the ^•alle\■ is obstructed by a broad spur of shale, which remains there because the stream has become engaged in the limestones on the flank of the main range, in which it has cut an impassable chasm. The trail climbed the shale spur, which we then recognized to be, like the terraces at the other end of the Serani Valley, a remnant of an old wide-open valley floor, 400 or 500 feet above the present stream. The chasm by which the stream passes around the spur is therefore to be regarded as a result of a local wandering of the stream 50 EXPLORATIONS IN TURKESTAN. to the northeast side of its former valley floor before the revival of erosion ; so that, when the recent downcnitting began, the stream became superposed on the limestones, from which it has not yet been able to escape. The spur gives location to a cross-trail, b}- which the Persian villagers in the headwater valle\s of the Atrek system traverse both the limestone anticlines on their way to Askhabad. Leaving our pack train to make camp on the stream (altitude about 6,ioo feet) just beyond the shale spur, Huntington and I, with one of our jiggits, followed the cross-trail to a high pass in the main range, and then climbed on foot to the summit of Chapan (about 9,300 feet), where we enjoyed a grand view in all directions. Riza, the highest summit of the region (9,732 feet, according to the Russian map), lay a mile to the east — a broad dome, in which the limestones were nearly hori- zontal, as they were indeed all along the mountain crest. The slope toward the Serani Valley was moderately dissected ; the slope toward the plains, 8,000 feet below us on the north, was deeply gashed with enonnous ravines. Askhabad was clearly in sight, being only about 20 miles distant ; the farther plains faded away in the haze of the lower atmosphere. It was diiScult to realize, while we were enjoy- ing the fresh, clear air of the mountain top, that the plains were still as hot as we had found them a few days before in the glare of noon on the railroad. The Firuza synclinal basin was reviewed ; its inclosing monoclinal range was seen to be of moderate length, perhaps 20 or 30 miles ; the syncline of the basin was tenninated on the west by a great anticlinal dome, on whose northeastern flank a curious meandering gorge is cut in the slanting limestone, probably another case of struc- tural superposition. The view southward into Persia showed a broad synclinal shale basin south of the Buuzan anticline, and several other limestone anticlines, with which we made closer acquaintance on the following day. What with form and color, it was comparatively easy to sketch the general structure for miles around. We followed the Serani stream nearly to its head on June 2. A second chasm, due to stream displacement, was passed about 2 miles above the first; then the valley shallowed rapidly, and soon opened in a broad upland, about 7,000 feet in altitude, which we may call the Chibin upland, from a spring that is noted on the map at its southwestern end, and here we came upon some Kurds in their summer camps. On the south rose the narrow and sharply serrate anticline of Giluli peak (9,378 feet), which seems to open and blend with the main anticline farther south- east, and which soon weakens to the northwest, leaving a broad and low ridge between it and the Buuzan anticline. These two ranges are so closely in line that they should be regarded as parts of a single upfolding, the variation in height along the line being probably referable to differences in degree and sharpness of folding, and perhaps in part to faulting. THE SELSUPARALI BASIN. Our road led us across the lowest point of the broad ridge, which we approached by gentle ascent from the Chibin upland on the north; but its aspect changed when, on looking down its .southern slope, we found there a rapid descent of 1,000 or 1,500 feet into the open basin of the broad Selsuparali shale syncline. This basin is drained through gorges in the Isferanli anticlinal EXCURSION INTO PERSIA. 51 range b\- headwaters of the Atrek wliich finds its way westward through the mountains to the southern Caspian. On account of the lower level of the Persian than of the Turkestan drainage system at this point, one of the headwaters of the Atrek system is actively gnawing its way through the escarpment at the lowest part of the divide into the Chibin upland and capturing drainage from the headwaters of the Serani Valle\'. Fig. 28. — Two-mile profile of Terraces at Namali, looking east. After studying the view from the crest of the unsymmetrical divide, we descended by a zig-zag trail and hired permission to camp in a grassy apricot orchard, among irrigated fields on a narrow valley floor at an altitude of about 5,500 feet. Above us was the village of Namali, a cluster of mud houses on the end of au interfluve. The village had seemed picturesque enough when first seen from the escarpment, but it appeared squalid and miserable on nearer approach. In the afternoon I ascended one of the interfluves for a review of the district. Like the Serani Valle\-, the Selsuparali basin shows signs of re\-ived erosion. The mature branching streams occup\' vallej-s 200 or 300 feet below the even- topped interfluves, whose fairly accordant levels indicate pretty clearly that the weak shales of the basin had been reduced to a peneplain before the \-alleys were eroded. There were, furthermore, faint signs of earlier cycles of erosion, not perceived at Serani or Firuza, and hardly worth recording here but for their confirmation farther east on the following day. The earliest cycle is indicated by the round-shouldered fonn of the Isferanli and Akh- kemar limestone anticlines on the south and southeast of the basin, where the cur\-ed surface over the crest trun- cates the strata, as if with reference to a baselevel of which there is no record preser\'ed in the less resistant shales. Certain benches on the mountain flank back of Namali appear to be remnants of graded spurs at an intermediate level. Then come the interfluves and the valleys of to-day, as shown in fig. 28. The broad synclinal basin of Selsuparali, between the Buuzan and the Isfer- anli anticlines, becomes narrower southeast of Namali, where the closely folded and serrate inclosing ranges may be named the Giluli and the Akh-keniar, after their chief peaks. On June 3 we followed the longitiidinal consequent Namali stream Fig. 23. — Two-mile section of Synclinal Valley, southeast of Namali. 52 EXPLORATIONS IN TURKESTAN. to its head, about 6 miles distant. While crossing the headwater col, as well as while descending the opposing longitudinal stream of Duruigar Valley southeast- ward, we passed a number of Kurd encampments. The valley was well inclosed at the col by the steep mountain walls, where great triangular sheets of limestone rose between successive lateral consequent ravines. The floor of the col, smoothly worn on the shales of the \-alley syncline at an altitude of nearly 7,000 feet, seemed to belong to the earlier cycle of erosion; the opposing longitudinal streams have intrenched their competing valleys so as to leave terraces of the older floor on either side, as in fig. 29. We camped on the further stream, about 10 miles from its head, and went up on the terraces in the afternoon. THE TERRACES OF DURUIGAR VALLEY. Successive cj'cles or impulses of valley deepening in the eastward extension of the s)nclinal valley were shown here more clearly than near Namali. The southern anticlinal range, now called the Telli Dagh, showed unmistakable graded slopes beveling the inclined limestone strata far up toward the crest of the range, as in fig. 30 ; remnants of sloping terraces occurred on the shales at less altitude ; then came the chief terrace, below which the present valley floor is eroded along the axis Fig. 30. — Two-mile profile of Terraces in the Duruigar Valley, loolung east. of the shale syncline. The period in which the upper limestone slopes were beveled and graded must have been the longest of those here shown ; the later periods pro- duced graded slopes onl)- in the weak shales. It may be noted, however, that, by whatever process the terraces were produced, their record of terracing impulses is probably incomplete, for the reason that each long-lasting period of wide-valley erosion must have obliterated the work of earlier, shorter periods. In the ideal case of eight impulses to deeper erosion and terracing, shown in fig. 31, the records of only three are preserved to-day. In such cases it is only the successively smaller and smaller maxima of the whole series of impulses that make themselves known, as is well shown in the beach lines made by successive storms of decreasing intensity ; for example, in the so-called "curbs" of tile great Chesil bank of southern England. The four valley floors in the Kopet Dagh must not, therefore, be taken to imply that there have been only four periods of renewed erosion ; there may have been many more. It is difficult to detennine the cause of the terraces by which the ^•alle^•s in the Kopet Dagh are ornamented. Terraces may result from certain changes of climate on a stationarj' land mass ; or from uplifts of the land in an unchanged climate ; or from TERRACED VALLEYS. 53 Fig. 3 1 . — Scheme of Terrace Development. the interaction of these two causes. The slope that would lead, in the present altitude of the mountains, from the high-level floor of the Serani Valley through the former floor of the Firuza gorge to the plains, seems rather steep for a graded valley, its fill being about 4,000 feet in 20 miles ; yet it does not seem impossible that under a climate even drier than that of to-day such a grade might have been developed and maintained by a stream of small volume and abundant load, after which a moister climate would pennit \alley erosion to a greater depth. On the other hand, it is manifest that uplifts of the mountain mass, whereby the streams were periodically accelerated, would result in terraces of a depth proportionate to the amount of uplift, and of a breadth proportionate to the interval of time between uplifts. The choice between these two possible explanations is not advisedly made by following a preference for one or the other, but rather by means of some crHx\, which contra- dicts one explanation and supports the other. This crux may perhaps be found on further exploration, if the terraced valleys are found to interlock in such fashion that no simple movement of uplift could ha\-e accelerated all the terracing streams, as is believed by Mr. Huntington to be the case for the Tian Shan valleys. Our few days in the Kopet Dagh did not enable us to apply this test there. We continued southeastward on June 4 along the Duruigar \"alle^•. It soon widened ; the Telli Dagh, on the south, becoming a broad anticline with moderate dips, and the Kara Ilikhi, as the continuation of the Giluli range is called, on the north, seeming to be cut oflf b>- faults. In the wide \-alle\- thus fonned the shales have been broadh- planed and covered with from 50 to 150 feet of gravel in con- tinuation with the chief terrace seen on the preceding afternoon. A patch of higher terrace, associated with a beveled limestone slope behind it, was seen on the side of the Kara Ilikhi range. The modem xalley is cut about 300 feet beneath the main terrace, and here has gained a width of half a mile at an altitude of about 4,800 feet. Leaving the valle\-, we crossed the gravelly terrace plain eastward, and after about 3 miles descended to the Russian frontier post, Gaudan (about 4,440 feet altitude), on the great Meshed-Askhabad road, which had crossed the terrace plain somewhat to the southeast of our trail. The main anticline of the Kopet Dagh here breaks down in some manner, but is soon replaced by the Suru-nuizdar anticline, an open but crooked vallej- separating the two. The bend of this \alle\- into the vSuru-muzdar anticline seemed to give opportunity of seeing the basal members of the heavy mountain-making limestones, but we had no time to leave the road to search for them. The head of the valley is gnawing southward into the broad, gra\el-covered terrace. The road follows northward along the valley, which is manifestly enough guided by an oblique fault as it opens on the plains ; for here we had the eastern dips of the heavy limestones overlaid with the shales of the main anticline on our left, and a bold scarp of the same limestones in the obliquely breached Suru-muzdar anticline on our right. Farther on the shales were be\eled in smooth, graded slopes, co\-ered with 100 or 200 feet of cobbles and 54 EXPLORATIONS IN TURKESTAN. gravels, and now dissected b}- the re\i\ed streams in ravines from 300 to 500 feet deep near the mountain base, but shallowing as the graded slopes descended to the plains. The return along the road from the frontier to Askhabad, some 30 miles, we covered rapidly in carriages. The net results of the excursion into the Kopet Dagh, in so far as they bear on the work of the expedition, are as follows: A series of changing conditions has prompted the streams to tenace their \-alleys at se\'eral le\'els. The sticcessi\'e changes in the beha\-ior of the streams indicated by the terraces ha\e probably had some recognizable effect in changing the character of the piedmont deposits ; the latter changes may possibly be recognized b)' borings and may then be correlated with the changes in the mountain valleys. It is ven,- probable that terraces similar to the ones that we saw occur in other parts of the range. If the valleys were examined at intervals of 30 or 40 miles all around the border of the plains on the south and east, it might be possible to connect the dates of the several terraces on the west with the history of the Quaternary Aralo-Caspian Sea, and on the east with the glacial records of the more lofty ranges. Thus successive piedmont deposits could be dated. It is evident, however, that there are many difficulties in the solution of such a ])roblem, and that much time and patience would be required before a solution could be reached. Yet in no other way does it seem possible to decipher the recent history of the piedmont fluviatile deposits. THE DESERT PLAINS. The railroad journey across the desert plains from Askhabad to Samarkand with three days stop at Old Merv, was extremely interesting, even if monotonous. The surface was absolutely plain to the eye, except for the dunes, and the dunes departed from the plain only as \vind-wa\-es at sea depart from a calm surface. Although apparently level, the plain has slope enough to give the Tejen, the Murg-ab, and the Amu rapid currents, in which these rivers carry forward a great volume of mountain waste. Mushketof (1891) describes this part of the plain as of fluviatile origin. Obruchef does the same, adding that the thickness of the river- laid layers is only several fathoms (1887 ; 1890, 247). The rivers have great varia- tion of \olume. The population of Mer\-, depending entirely on the Murg-ab for irrigation, had crops abundant enough in 1891 to export some of the surplus to Russia; and in 1892 had but little more than half the ordinary yield (Tarnovski, 1895). We were fortunate enough to see the Tejen and the ]\Iurg-ab in flood. The former had overflowed its channel and spread in a thin sheet for miles over the plain. The latter would have spread but for the restraint of dikes at IVIerv. Some of its waters had escaped further upstream and came to the railroad, wandering across the plain among the dunes, a curious combination of too much and too little water supply. The rivers had been still higher a few weeks before our arrival, and the Tejen bridge had been carried away, as well as some of the track on the plain west of Merv, causing great delay to traffic and especialh- to freight transport. By the time of our arrival, June 10, a temporary foot-bridge had been built across THE DESERT PLAINS. 55 the Tejen, and the track elsewhere was relaid sufficiently to allow trains to cross the breaks at low speed. An engine that had approached the flooded Tejen too closely was seen mired in the softened mud of the plain ; the track had collapsed under it. THE .\GGRADING RIVERS OF THE PL.\INS. The most notable feature of this district was the absence of valleys. The rivers have channels in which their waters are usuall}- restrained, but there were no valleys in which the river floods were limited. The plains were open to overflow as far as flood supply held out. We were told, however, that some distance upstream (to the south) the IVIurg-ab has a flood-plain slightly depressed beneath the plain. This we interpreted as meaning that the river had there changed its habit from aggrading to degrading. On crossing the Amu at Charjui we saw a low bluff on the north or right of its course, although on the south the plain is not significantly above the river. The general absence of valle>s is a natural, indeed an essential, feature of a fluviatile plain in process of aggradation by flood deposits. It is peculiarly appro- priate to rivers like the Tejen and Murg-ab, which dwindle away and end on the plain, so that even- grain of sand and even,- particle of silt must be laid down as the water volume lessens and disappears. The absence of \-alleys would, on the other hand, be surprising in a lacustrine or a marine plain, for the reason that coincidence could hardly be expected between the slope that might be given to such a plain when it is laid bare and the slope that is satisfactory- to the graded rivers that run across it. It is not, however, as has already been pointed out, always the case that fluviatile plains have no valleys eroded beneath their general level. The river-made plains of northern India are now commonly somewhat trenched by their rivers. Our Great Plains, piedmont to the Rocky Mountains, are likewise in pro- cess of dissection b>- their rivers. The plains of Turkestan are therefore somewhat exceptional in this respect. As a result we had unfortunately no opportunity of seeing sections of the plains in which the structure of the deposits could be examined. A well on the Czar's estate at Bairam Ali, a modern \-illage near Old ]\Ier\-, where we were most agreeably entertained by the superintendent, Mr. Dubassof, was said to have shown nothing but " .sand and loess." The desert and river deposits found by borings beneath the Anui River bed at Charjui have already been noted. The inspection of these vast plains of silt was very suggestive in connection with the problematic origin of the fresh-water Tertiary fonnations of the western United States. Certainly no one who sees the river-made area of the plains of Turkestan can doubt the capacity of rivers to lay down extensive fine-textured deposits. The ruins of old IMer\' are situated on the fluviatile plain, where large canals must have once led a plentiful water-supply from the upper Murg-ab. They lie some 1 2 miles east of the oasis of modem ]\Ier\-, in which the greater part of the river is now used for irrigation. It is therefore especially desirable to make careful exam- ination of the earliest of the ruins with respect to the level of their foundation and its relation to the surface of the surrounding plain. Some of the ruins are only a few centuries old ; the cities that they represent are known to history. Others have 56 EXPLORATIONS IN TURKESTAN. the appearance of much greater age, being more completely decayed. The largest of these, Gliainr Kala (fig. 32), a group of huge mounds within a degraded wall, must have had a beginning very long ago. The relation of its earliest, deepest-lying artifacts to the strata of the plain deserves the closest scrutiny. As no sections could be found, it is impossible to say whether any subdivisions can be established in the fluviatile deposits of the plains. The best means of deter- mining this point would be by the aid of a soil auger, the use of which is to be recommended. As an encouragement to study of this kind, it should be remem- bered that graded rivers, like those of these desert plains, are in a ver^' delicate Fig. 32. — The Central Mound o( Ghaiur Kala. from 60 to 80 feel high, in Old Merv, looking north. adjustment, and that a change of climate or a change in the altitude of their head- waters should e.xpectably produce a change in their regime. During a moister or cooler climatic period these withering ri\'ers must have been longer than they now are ; indeed, they would probably be longer than they are to-day if their waters were not distributed over the fields of the oases. There is good reason for believing, as various observers have suggested, that the Zerafshan would now reach the Amu but for its use on the fields of Samarkand and Bokhara. But whether the climate of the region has been moist or cool enough in Quaternary time to extend the Murg-ab and the Tejen so that they might join the Amu, as has been suggested, has not yet been proved. BARKHANS OF THE KARA-KUM. 57 The right-handed shifting and bhiff-cutting of the Amu, as a result of which the admirably irrigated and fertile oasis of Charjui is on its left side, has been taken as an illustration of the deflective force of the earth's rotation (cf Walther, 6r, 114)- but it is still questionable whether this small force is sufficient to produce the results that are ascribed to it. The doubt on this point has greatly increased in my mind by reason of the measured deflection of the Mississippi, as detennined recently by one of my students from the maps published by the Mississippi River Commission, he- iii& greater on the east (left) than on the west (right) in a period of twelve years. In any case, the bluff"-cutting by the Amu must be determined by some other cause Fig. 33. — Sand Dunes south of Charjui, looking northwest. besides the earth's rotation, inasmuch as it involves not mereh- a right-handed shifting, but a degrading action at the same time; and degradation by such a ri\er implies some alteration in individual regime, such as climatic change or crustal mo\ement would produce. The railroad crosses a tract of typical crescentic dunes (barkhans) before reach- ing the oasis of Chaijui on the Amu. Some areas had scattered bushes among the sands; others were essentially without vegetation, and there the dunes were at their best (fig. 7,2,). They were under the influence of northerly winds, for their longer slopes were to the north, and their steep scarps and lateral horns were to the south. According to Russian obsen,ers, the fonn of the barkhans has a seasonal variation, following the change in the prevailing winds. Besides the seasonal variation of dune fonn, there appears to be a secular extension of the dune-covered area, in some places averaging 20 feet a year (Walther, 1900, 119). 58 EXPLORATIONS IN TURKESTAN. The dune-co\-ered area was abrupt!)- cut off as we eutered the irrigated fields of Charjui ou the plain bordering the Amu on the south. The fields of the gently sloping plain are delicately graded to level surfaces, each fed by a little canal and bordered by a little dike next to its lower neighbor. The canals are divided and subdivided, like nerve endings, the smallest ones being hardly noticeable. Many of them are bordered with trees. The houses and the walls of inclosed gardens are of gray, sun-dried mud. There are no fences between the fields ; hence horses and cattle are tended or tethered while pasturing. Grain, lucern, and cotton were the principal crops noted. The change from the desolate sands to this thriving oasis was a beautiful example of the beneficent work of irrigation in the desert. LOESS DEPOSITS. It was suggested by Professor Penck, during our conference with him at Vienna on the outward journey, that special attention should be given to deposits of loess, in order to detennine in how far they are now in process of accumula- tion, or in how far they should be referred to .some period of past time. This problem was made the more interesting by seeing at Krems, on the Danube, above Vienna, a well-defined deposit of loess from which some 15,000 artifacts have been gathered by the patient work of Dr. Strobl. Some specimens of rudely chipped flints were kindly given to us to serve as samples of things to be searched for in the loess of Turkestan. Our hurried movements made it impossible to undertake any such search, or indeed to make any close examination of loess-covered areas ; but we passed certain loess deposits regarding which our observations, even though made only from train windows or from post-wagon, seem worth placing on record. LOESS NEAR SAMARKAND. On approaching Samarkand, June 15, the railroad crosses an extensive deposit of loess, at once seen to be unlike the gravelly piedmont slopes near Bokhara, and equally xinlike the sea of sand-dunes on the plain south of the Amu, but not easily distinguishable in a passing view from the fine silts of the Murg-ab and the Tcjen plains, e.Kcept that the surface of the deposit here was not level, but broadly undulating and sub-maturely dissected. A 30-foot cut, where the railroad made its way between opposite valley heads, was unfortunately passed in the twi- light. At Samarkand a deep valley is cut in loess, well seen a short distance east of the railroad station. A few miles farther on, near the ridge across the Zerafshan, the hill slopes are cloaked with loess, on which a thin cover of angular waste has crept down. All these deposits, therefore, seem to be and to have long been in process of dissection rather than of accumulation. It occurred to me that even if other conditions were now favorable for the accumulation of loess in this district, the irrigation and cultivation of the Zerafshan flood plain is distinctly unfavorable to its accumulation ; for the cultivation of crops and, perhaps even to a greater extent, the growth of trees, lifts the wind from the ground, and thus greatly diminishes the amount of fine silt that can be carried from the flood plain and deposited elsewhere. In the absence of cultivation the flood plain LOESS NEAR JIZAK. 59 would be relatively barren and the finer material would be blown from it with relative ease. It is here assumed that the loess is not chiefly supplied from the products of weathering on uplands and mountains, where the finer soil has less lime than loess contains, but that it comes in greater part from flood plains, where the finer silt, largely produced by the mechanical attrition of cobbles and gravels, may be highly' calcareous, as has been pointed out by Penck. LOESS NEAR JIZAK. A loess deposit of unusual interest was seen on June 17 on the uplands north of the Zerafshan, where the railroad contours around the eastern spurs of a detached part of the Turkestan range, west of the valley of the Sankar. The Sankar follows a valley that is rather sharply cut down in an upland or local pene- plain. The upland and the loess upon it are briefly described by IMushketof (1886, 355). The valley is about 100 feet deep where the railroad enters it, but the depth increases to 300 or 400 feet farther north, where it opens on the broad Fig. 34. — Diagram of Railroad Cut, south of Jizak. Hunger (Golodnaia) steppe near the town of Jizak. The valley floor is usually about a quarter of a mile wide ; it narrows where a belt of harder rocks forms "Timur's Gate." The valley sides are graded, except for the outcrops of the most resistant ledges. The upland or peneplain, where it is preser\-ed on the spurs between the numerous side valleys, truncates the disturbed rocks of the district ver>' evenly. The side vallejs that dissect it are fairly well open and graded far up the mountain slopes on the west. Kurgans (mounds) occur in some of these valleys. As the steppe is approached, the side valle)s increase in depth and width, and the even upland of the spurs is replaced b)- maturely rounded hills. Then the steppe suddenly opens, as if the upland were terminated by a fault or sharp bend; for if the level of the upland were prolonged northward it would run out into the air, far above the present plain. Its even profile was well seen by looking back from the train after we had run some miles out on the plain. The main and branch vallej-s of the Sankar must have been eroded after the faulting and uplift of the district with respect to the steppe. The railroad must be man}' hundred feet abov'e the main valley where it crosses the divide between the Zerafshan and the Sankar ; it descends to the Sankar across many of the spurs and side valleys, cutting the first and filling the second. Our train ran at moderate speed and we had a good sight of the cuts, whose fresh walls disclosed sections that are generalized in fig. 34. A somewhat uneven rock floor was cloaked with loess to a thickness of 10 or 15 feet. The loess contained sharply 6o EXPLORATIONS IN TURKESTAN. irregular partings, carrying a thin deposit of angular stony waste ; it also showed faint color bands, nearly horizontal, which were distinctly cut b)- the slopes of the spur sides ; hence the valleys were regarded as younger than the loess. If this interpretation be correct, there is reason for thinking that the loess of the spurs is older than the uplift on the north-bounding fault, by which tlie revival of valley erosion was prompted. Evidently, then, this loess deposit ceased accumulating long ago, and has since then been much eroded. The fine loess-like deposit of the southern part of the Hunger steppe is colored as river-wash on Muhsketof's map. Its surface is gently rolling, and the railroad cuts in the swells repeatedly show its fine, unifonn texture. Near the mountains on the south it is traversed by the flat- floored valleys of dwindling streams, where we saw many cattle pasturing. The uplands and loess-capped spurs over the Sankar Valley, and their relation to the Hunger steppe, impressed me as particularly well worth a closer stud)'. A considerable area of dissected loess was passed after the railroad had crossed the Syr on the way to Tashkent. Like the other deposits, this showed every sign of having long submitted to normal erosion. Where the S}t swung against it there are vertical bluffs lOO feet or more in height. LOESS IN FERGANA. The interesting ride through the Fergana basin, from Chernyayevo junction, on the main line, eastward to the end of the branch line at Andizhan, deser\-es mention in this connection, from the striking suggestion that it gave of the conditions, fiivorable and unfavorable, for the supply of loess from rivers. At various points, as near Posieto\ka, Kokan, and Andizhan, there were extensive plains of gravel, washed, from time to time, by the flooded streams from the mountains on the south. The plains were usually barren and open to the action of the wind. Dunes were sometimes seen upon them. Such surfaces might afford much silt fine enough for carriage by the winds, after the floods that bring the silt subside. Neighboring areas of fine soil were irrigated and seemed richly productive with crops of cotton, wheat, rice, and lucern, with vines and fruit trees, and many rows of poplars. Much silk is produced here. It is woven in se\eral of the cities. Many cases of cocoons are sent to France. The silt is deposited in the fields by the turbid irrigating streams, as well as by the winds, and is protected from the winds by the trees and smaller plants. There can be little question that the occupation of this basin for many centuries past has caused a considerable deposit of silt on the cultivated areas and held it from being swept away to the uplands by the winds. If the water were not led about in canals and spread out on delicately terraced fields it would nm wild, and much of the silt that is now detained under plant protection would be more open to wind transportation from the torrent flood plains. Culti- vation thus seems to be distinctly favorable to the deposition of stream-borne silt on the valley plains and unfavorable to the deposition of wind-borne loess on the neigh- boring uplands. LOESS IN FERGANA. 6 1 There is, however, another condition that is even more adverse to the suppl)- of wind-borne silts. This is found where the streams have incised their courses in narrow gorges instead of broadly spreading their floods over torrential fans; that is, where the streams are engaged in degrading instead of aggrading their beds. We crossed a degrading stream about 7 miles west of Khojent. It had for some reason cut a sharp and deep trench in the plain, so that it was not seen until we were close upon it. There was no possibility of its overflowing the plain, and so all its silt was washed along its channel. The sprawling and shifting streams else- where seen on the fans were in most marked contrast to this secretive river. Hence, in so far as loess is derived from rivers, there can be little question that it comes from aggrading rather than from degrading streams ; and this conclusion seems to be applicable to the loess of the Alpine region, as described by Penck, and to that of the Mississippi basin, as described by Shimek and others, as well as to that of Turkestan. The ride through Fergana was most entertaining from its variety. The great snowy ranges of the Alai rose in the south. Their Alpine crests and snow fields were brilliantly clear in the early morning. By noon they were much hidden under diurnal cumulus clouds. We could see, with our field glasses, man)- features of gla- cial origin, further described below. Northeast of Khojent was an e.xcelleut exam- ple of one of those sharply dissected ranges at whose base a series of digitate spurs interlock with branching valley floors, so as to make a most sinuous base line, in strong contrast to mountain ranges of simple border, like the range south of Jizak. The latter seems to belong to the class of somewhat dissected fault blocks; the former, if it ever had a faulted front, has lost all signs of it. South of Maxrani rose a high dissected dome of apparently crystalline core, wrapped around by colored sedimentaries — first, a dark belt that lapped on the flanks of the dome, then a weak gray belt; then more resistant red beds. The colored belts are nmch narrowed as they curve around the northern base of the dome from east and west, as if they were torn by marginal faulting or tilted to steep dips. Dissected fans stand forth from the larger ravines of the dome; younger and smoother fans are built at their base ; then come the gravelly flood plains of the streams, with many dunes heaped on them. Near Marghilan we passed benches of uplifted gra\-els, probably corresponding to the uplifted and dissected sub-recent ridges that we saw a few days later on a ride south of Andizhan. Here the strata dipped 10° or 15° north- ward, and fine gray silts alternated with coarse gravels. Similar alternations of gravels and loess-like silts were seen in the borders of the Kugart \'alle>', where we entered the Tian Shan ranges on June 30. LOESS IN SEMIRVETSHEKSK. Much loess was seen on the steppe west of Vyernyi at the northern base of the Trans-Ili Ala-tau ; it seemed less dissected than the deposits west of Samar- kand and south of Tashkent. More remarkable deposits of loess were seen while posting across Semiryetshensk — the Seven-river district — from \'yemyi northward 62 EXPLORATIONS IN TURKESTAN. to Seuiipalatinsk, July 28 to August 2, in several headwater valleys of the Karatal, a river that flows into the mid-southern side of Lake Balkash from the western spurs of the Cis-Ili Ala-tau. Near the village of Kugalinsk (see sheet 12 of the 40-verst Russian map), the northwest slopes of the Chulak range were cloaked with grassy loess and somewhat dissected by small consequent valleys, across which the road had many ups and downs. On the ridge between Kugalinsk and Tzarat- zinsk the slopes are strewn with irregular pig. 35.— Diagram of Loess Drids. near Kara-bulak. mounds of loess of small relief, in which looking south. the roadside cuts were creamy white. The surface was well covered with grass ; hay had been cut in places. On the ne.xt ridge, which divides the Kok from one of its branches, there was a curious mixture of fresh and hackly ledges and smooth mounds of loess, in which some road-cuts were 10 feet deep. The mounds seemed to have a trend from the northwest or west-northwest, and occurred up to altitudes of 4,000 or 4,500 feet. The valley of the Kusak, near Kara-bulak village, afforded the most significant features, for here the drifted form of the loess became verj' pronounced. The vallc)- floor, at an altitude of about 2,800 feet, very smooth and about a mile wide, opens westward between long spurs descending from the range on the east. The stream has cut a narrow trench, 20 or 30 feet below the floor, along the base of the northern spur. The current is rapid, with large cobbles on its banks. A few miles to the west the trench opens on a broad, fan-like plain, where the road was very rough from the abundance of rolled stones. The valley-side spurs were covered with loess drifts, hundreds of feet in length, thinly overgrown with herbage, somewhat barkhan-like in form, gracefully convex in their longer ascent from the west and falling off steep to the east ; crowded together and overlapping like a school of fish hurrying upstream ; more closely packed to the west, and thinning out to the east. Their form is too systematically drawn in fig. 35. The difference between these aggraded drifts and the normally dissected slopes of the spurs of country rock farther up the valley was very striking and suggestive. The latter had all the down-hill lines that indicate the work of ordinary erosive forces, and repeated the ravined forms so familiar elsewhere. The former showed no sign of down-hill grading, but expressed most clearly the sweeping of the wind over their graceful curves. Hence, unlike the deposits near Samarkand and Tashkent, the loess here is of so recent a date as to be uuchanneled. It preserves most perfectly its wind- swept form; it may still be growing. The phrase, "wind-swept form," is used because, although the loess drifts are now covered with scanty herbage, the profile of the drifts, gently convex to windward and falling more abruptly to leeward, suggests that the actual motion of the wind has had nuich to do with shaping them. As to the constitution of the drifts, we had the most convincing evidence while descending across them on the southern side of the valley. An impalpable white dust was raised in a blinding, smothering cloud by our galloping horses and rolling wheels ; and the penetrating power of the dust here and elsewhere was LOESS IN THE TIAN SHAN MOUNTAINS. 63 shown at the end of the ride by the condition of our clothes, which had been carried in a well-wrapped valise, unwisely tied on at the back of our tarentass. The form and distribution of the drifts by Kara-bulak leaves no doubt as to the recent derivation of the loess from the plains on the west and northwest. Not only does the fan-like flood plain of the Kusak open in that direction, but the great sandy wastes of the lower Hi and Karatal, south of Lake Balkash, stretch for scores of miles beyond. All this gives further support for the supposition that, in this region at least, loess is not derived from mountains, but from the river plains. To be sure, the waste that is laid on the plains comes originally from the waste of the mountains, but in the mountains the slopes are often plant-covered, and are therefore better fitted to gather loess than to furnish it, as seems to be attested in the loess mounds that have been so manifestly laid up on the ridges over the Kok River above mentioned. It is not from ordinary river valleys that loess is best supplied, but from the open plains of aggrading rivers ; and, moreover, it is chiefly while the aggrading rivers are wandering over their plains that loess can be furnished in greatest quantity, as was pointed out in the notes on Fergana, above. The former broad valley floor of the Kusak by Kara-bulak, for example, is not to-day in condi- tion to furnish loess, because it has been plant-covered since the river has intrenched itself below the plain, and the river trench is as yet too narrow for the outspreading of silts. Further west, where the same river emerges from its trench to wander upon a broad plain, loess ma}' now be swept off in good quantity' by the westerly winds, to settle on the plant-covered hills. LOESS IN THE (western) KUGART VALLEY. The loess drifts of the Kusak valley-sides give me confidence to put on record certain notes made in the valley of the (western) Kugart, in the outer spurs of the Tian Shan, about 20 miles northeast of the town of Jellabad, in northeastern Fergana. The treeless hillsides seemed often to be loess-covered, and in many places the loess had slipped down, leaving a scar. Ravines were worn through the loess, hence it was not of verj- modern date. The loess and the \-alley floor were well covered with herbage. But the most significant feature was the drift-like appearance of the loess; it seemed to lie in pillow-like masses (fig. 64), whose lines of modeling were not down-hill, except where the drifts were gashed by ravines, but along the hillsides, as if here it had been wind-swept down the valley to the southwest. We asked our jiggits, who had been detailed by the native chief of tiie department to accompany us to the head of the pass, from what direction the wind blew in winter; and the answer was, "Strong from the northeast" The Kugart River is to- day intrenched from 300 to 400 feet below its former valley floor, which was here a mile or more wide. The terraced walls of the trench show the valley to have been heavily aggraded with gravels and sands. It is therefore probable that the loess on the hillsides was largely supplied from the valley floor during the period of aggradation, and that since terracing began the accumulation of loess has ceased. 64 EXPLORATIONS IN TURKESTAN. THE TIAN SHAN MOUNTAINS. The general geology of the mountain ranges that border the plains of Turke- stan on the east is too large a subject and too little connected with the special interests of our expedition to have been itself an object of special study by our party. Moreover, it is precisely in general geolog)' that Russian explorers have done such excellent work in this region. But the more modern histor}- of the mountains, as recorded in their physiographic development, seems to have been less examined ; and since this phase of the subject is closely associated with our study of the plains, we gave it our first attention here, as we had previously done in the Kopet Dagh. My own report deals with the Tian Shan ranges between the provinces of Fergana and Semiryetshensk. The report of Mr. Huntington sets forth the results of his visit to Kashgar after leaving me at Issik Kul. The report hereto appended by Mr. R. W. Pumpelly tells of his observations on the mountains south of Fergana during a visit to Lake Kara Kul on the Pamir. PREP.^RATION FOR THE MOUNTAIN JOURNEY. My party from Andizhan across the moimtains to Lake Issik Kul included Mr. Huntington as assistant and Mr. Brovtzine as interpreter. General Ivanof, governor-general of Turkestan, had given us during our stay at Tashkent letters of introduction to various officials; among others, to the governor of the Andizhan district, Colonel Korytof, from whom we had much a.ssistance in securing our outfit. He detailed a member of his police force, a Sart of marked intelligence, to act as our head-man and cook, and we had much efficient service from liim. A second man was engaged to look after our three pack horses. We received generous aid also from Captain Asatians, secretary of the Military Club at New Marghilan, where we went for certain supplies. It was by Mr. Polovtzof, diplomatic official at Tashkent, and his .secretary, Mr. Andreef, that we had been given the practical suggestion of carrying colored handkerchiefs of bright and varied patterns, to serve as small change when paying the Kirghiz for supplies of mutton and milk and for service as guides in the mountains. We had a small canvas tent, but seldom found occasion to use it, as the clean felt tents or " yurts " in the summer camps of the Kirghiz, well furnished with felts, rugs, and silk quilts, were much to be preferred in the cool and occasionally rainy nights in the mountains. We carried no firearms. Besides the local sheets of the 40-verst map of the " Southern Boundary of Asiatic Russia" (1889), blue-print copies of the contoured 2-versts-to-an-inch map, as far as the sheets were completed along our route, were supplied to us by Major-General Gedeonof, chief of the topographical office at Tashkent, and we can testify to their accurate expression of surface forms. While at Andizhan we had the good fortune to meet Academician Chernichef, director of the Russian Geological Survey, and his assistant, Mr. Korolkof, on their return from a journey to Kashgar. Professor Chernichef gave us much information from his unpublished notes on the geologi- cal structure of the mountains; and Mr. Korolkof gave to Mr. Huntington a letter of introduction to his father, General Korolkof, in Przhevalsk, at the eastern end of Lake Issik Kul. PREPARATION FOR THE MOUNTAIN JOURNEY. 65 Andizhan had been badly injured by an earthquake a year before our arrival, and the Russian part of the city had hardly begun to recoxer from the destructive effects of the shock. Many of the inhabitants had left their shattered houses and still were living in box freight cars that were standing in trains on temporary tracks in the streets near the raihva}- station. In the absence of any hotel, we spent the few days of inevitable dela)-, while outfitting, in the small service car that had been obligingly put at our disposition by the railway superintendent at Tashkent, where we had left the rest of the party in the larger car that had brought us all from ]Mer\'. It was during this interval that we visited the ridges of tilted and dissected gravels and silts a few miles south of Andizhan, to which reference has already been made. One of the most interesting experiences of this part of our journey was the companionship, for the first three days, of Kambar- Ali, the ]\Iin-bashi or native chief (fig. 36) of the department of Kugart, through which we had to pass. Colonel Kor^tof summoned the Min- bashi to Andizhan the day before we left that city, and presented us to him as foreign travelers to whom he should show ever)' attention. The IMin-bashi accordingly met us shortly after sunrise on June 27, with his interpreter and several jiggits, or mounted police. Thus escorted, our cavalcade rode forth along shaded roads, through the fields and villages on the fertile and populous plain of Fergana. One of the jiggits, riding ahead, announced the coming of his chief, whereupon all other travelers dismounted and remained standing on the road- side to salute the Min-bashi and his party as we rode by. We lunched at a nati\e restaurant, where tea, rolls, and apricots were served. The first night was spent in the town of Kurgan Tepe, where we were the guests of another native chief, a friend of our host. On June 28 we crossed the Kara-dar}-a, a rushing, turbid river, in high-wheeled carts. The river was at that time about 200 meters wide in a mile- wide, barren flood plain of cobbles, gravel, and silt. The cultivated fields on the north and south were from 3 to 5 meters higher. We then crossed extensive wheat fields, owned by the Min-baslii, and were entertained for the night at our host's house, a spacious but simple residence near the village of Chanket. Here we met Fig. 56. — Kambar-Ali, the Min-Bashi of Kugart. 66 EXPLORATIONS IN TURKESTAN. several of his sons, but his wives and daughters remained in retirement in another part of the mansion. Among the objects of interest that were shown to us with justifiable pride was a photograph of chiefs and officers, the Min-bashi among them, who attended the coronation of the present Tsar. Although onr conversation was retarded b\- the necessity of two translations, the courtesy of our host never failed. When we took leave of him, on June 29, at one of his smnmer houses near the town of Jellabad (fig. 37), it was with regret that we lost so genial a companion. Three of his jiggits went on with us to the limits of his department. For four days we found that couriers had been sent ahead to make announcements of our coming, and to secure ns a welcome among the people of the uiouutaius. Kig. 37.— The Min-Bashi of Kugart and his Men. The Kirghiz were always helpful and hospitable. The Russians had described them as untrustworthy, and doubtless they resemble people in other parts of the world in including some who are lazy and evasive with others who are thrifty and truthful. Some of our felts were stolen in a village in the Tuluk Valley, but they were soon recovered. A similar experience has befallen me in a mining town in Montana. The leaders in the villages seemed to be men of energy and ability. They always received us with courteous attention and gave us of their best. In the midsummer season of our visit, the rude, mud-house winter villages in the valleys were almost deserted. We saw many of the houses open and empty; only a few men remained there to look after the irrigation of the wheat and grass fields. The rest of the popidation, with all their possessions, w^ere found in the high valleys. Around Son Kul in particular, at an altitude over 9,000 feet, we .saw great numbers of summer camps. The habit of life was that of seasonal migrants rather than THE KIRGHIZ OF THE MOUNTAINS. 67 strictly nomadic. Tlie chief men were certainly well-to-do, and seemed to want for nothing. One of these, Kuve Gen Shigai-ef (fig. 38), had been a judge among his people (fig. 39). He invited ns to lunch in his yurt at Akh Tash (White Stone) on the Son Kul plain. The yurt was one of the finest we had seen, with a hundred sticks supporting the clean felts of the roof His two wives, wearing heavv, white turban - like head - dresses, were seated by him, embroidering. His eldest son wrote the names of the family in my notebook in Turkish characters with a ready hand. The judge told us — through two trans- lators, as usual — some of his expe- riences in settling disputes, chiefly about pasture land, and gave us much information about our route, directing one of his sons to accom- pany us to his winter village, not far from Lssik Kul, a three days' journey. In another village, where the local chief was absent, his elderly father entertained us most genially. He was particularly interested in our maps, and asked many questions as to the names of mountains and streams, their distance and direction from his camp, and found much pleasure in confirming our readings by reference to his men. At the end of the evening's talk our host .said: "You have traveled far aud have seen much of the world; )ou must know many things. We are simple, ignorant people, who know only our own mountains and vallevs." Fig. 38,- Kuve-Gen-Shigai-ef, his Younger Wife and Children, and our Head Man, Ma'raim. ROUTE OVER THE MOUNTAINS. Our route, briefly indicated at the beginning of this report, may here be given in more detail in so far as the journey beyond Andizhan is concerned ; and it may be noted at the outset that there are wagon roads in the larger \'alleys, with bridges over some of the streams, while trails cross the mountains in all directions. In the prevailing absence of forests, movement is ea.sy, except in certain narrow and rock- walled gorges which some of the rivers have worn in their passage through the After leaving Andizhan on June 27, we went northeastward up the terraced valley (fig. 63) of the (western) Kugart River, a branch of the Kara Dan-a, following 68 EXPLORATIONS IN TURKESTAN. a wagon road half the way, and then crossed by a trail o\er Kngart pass in the Fer- gana range, about 10,500 feet altitude, in the afternoon of July i, and descended eastward, to camp in the \'alley of the (eastern) Kugart (figs. 67 and 68), a branch of the Narin, both the Narin and the Kara Dar\-a being branches of the Syr. On July 2 we crossed the Oi-Kain pass eastward to a branch of the (eastern) Kugart, and camped at Urgas-Khan, a summer village of Kirghiz, in a grassy valley at about 8,000 feet elevation. At noon of this day we o\-ertook a large caravan of horses and camels laden with merchandise for the interior. An open pass led us eastward to the headwaters of the Makmal on the morning of July 3, and after crossing a belt of badlands southward, we camped by a new bridge o\-er the Alabuga River. Here we met a Russian lieutenant of engineers, on his wa}' to superintend work on a Fig. 39. — Kuve-Gen-Shigai-e{ and some of his Men at Akh Tash, Son Kul. road over the Kugart pass. He had latel}- been in Kashgar, and gave Mr. Hunt- ington some useful suggestions about the road thither. We followed a good road down the Alabuga Valley northeastward (fig. 60) on July 4, and rested over Sunday, July 5, in the garden of a Kirghiz winter village, Tot-kui. On July 6 we reached the junction of the Alabuga and the Narin, and turned eastward up the Narin \'al- ley, camping for the night on the river bank at an altitude of about 6,500 feet, near a party of Sart sheep dealers, who had just brought a flock of some 3,600 sheep across the ri\-er with a loss of only ten, on their way to Fergana. Since July 3 the road had been in a dissected basin of Tertiary conglomerates and clays, which continued eastward far up the Narin Valley. On Jnl>' 7 we forded the Narin, and turned northward along a trail up a side valley, camping in the mountains with a party of Kirghiz, who were driving their THE ROUTE THROUGH THE MOUNTAINS. 69 flocks to summer pasture by Lake Son Kul. The next day, July 8, we went on with the Kirghiz, crossing the Dongus-tau range at about 10,000 feet elevation, reaching the lake about noon, and camping above 9,300 feet in one of the summer villages on its southern border, after an afternoon ride to a small glaciated valley. The gra}- }-urts of many Kirghiz encampments were dotted around the lake, and near each camp the grassy meadows gave pasture to camels by the score, horses and cattle by the hundred, and sheep and goats b}- the thousand. On July 9 we forded the outlet of the lake at its southeastern corner, went northward along the plains on its eastern side, visited two glaciated valleys of the Kok-tal range in the afternoon and then had our view of the flat-topped Bural-bas-tau range to the southeast; we camped in another summer village for the night. On July 10 we crossed the Kum-ashu pass in the Kok-tal range and descended northward to the Tuluk \'alley, camping again in a Kirghiz village. Having seen during the descent a large moraine in the Chalai range (fig. 49), north of the valley, we went up to it (fig. 50) on the morning of July 11, and in the afternoon followed down the Tuluk-su, eastward to its junction with the Juvan-arik (so-called by a post- master, but named Kara-khojur on the 40-verst map), and there stayed in the post station, Sari-bulak, on the road from Kashgar and Narinsk through the mountains to the open conntr}' of the north. On July 12 we went northward through deep gorges in the Yukok-tau range down the Juvan-arik to its junction with the Kach- kar River in the Kach-kar basin, south of the Alexander range, and rested at Serai Kara-gol over July 13. The river below the junction is the upper trunk stream of the Chu, which farther on escapes northward from the mountains and then flows far west to disappear on the plains ; but it is here called the Urta-Takoi. We followed it eastward on Juh' 14 and camped on the plain that borders the western end of Issik Kul at an altitude of 5,300 feet. On July 15 and 16 we made a detour south of the lake to see some glaciated valle}s in the Terskei Ala-tau range, camping the first night at a small spring in the mountains, and the second night enjoying the comfort of an excellent yurt at a summer village in the upper valley of the Ula-khol, an afiluent of the lake. On Jul\- x"] we returned to the west end of Issik Kul, where the rapid Chu makes a sharp bend from a northward to a westward course, and at the elbow gi\-es out a small distributar)-, the Kute-maldi, which flows with sluggish current eastward to the lake. On July 18 we followed the post road eastward along the north side of the lake and spent Sunday, July 19, at Turaigir station. We still followed the post road eastward on July 20 and 21, reaching the Russian village of Sazanovka. There Mr. Huntington left us on the morning of July 22, our head-man going with him, on the road around the east end of the lake, and thence southwest and south over the Tian Shan to Kashgar, as is duly set forth in his report. ISIr. Brovtzine and I turned northward, hoping to cross the Kungei Ala-tau range by the Sutto- bulak pass on the direct way to Vyemyi. We spent the night of July 22 at a Kirghiz camp in a moraine basin, at about 8,000 feet altitude, but on Juh- ij, were disappointed to find the valley head below the pass covered with decji snow. We attempted to beat a track for our horses (fig. 52), but gave it up on reaching the 70 EXPLORATIONS IN TURKESTAN. top of a fresh moraine at a height of over ii,ooo feet, near tlie end of a small glacier, and finding a mile of snow and nearly a thousand feet of ascent still before us. Our Kirghiz guides then .said they had known it would not be po.ssible for us to make the pass. We had asked tliem many questions the day before and they had promised to show us the trail. Their silence about the difficulty of the pass apparently resulted from a feeling of deference to foreign travelers. We returned to Sazanovka, sold our horses at about half purchase price, di.scharged our packer, and set out in post wagon (fig. 45), retracing the road along the lake through the afternoon and night of Juh- 24, descending northward through the Buam gorge of the Chu, between the Kungei Ala-tau and the Alexander ranges on July 25, crossing northeastward over the western branch of the Trans-Ili Ala-tau range in tlie night, following the piedmont plain eastward through the morning of Sunday, July 26, and reaching \'yernyi in the afternoon (altitude 2,400 feet). On Julv 27 we called on General Youof, governor of the province of Semi- ryetshensk, and on July 28 started for a ride of 1,000 versts northward across the steppes (fig. 48) in a tarentass, or springless post wagon (fig. 45). We made good time, stopping only to change hor.ses and for meals, and in spite of the loss of .seven hours from breaking one wheel and from binding another, reached Semipalatinsk, on the Irt\-sh, in the afternoon of August 2. The guest rooms in the post stations on the road were, with very few exceptions, clean and neatl\- furnished. Tea, bread, milk, and hone)' were among the chief articles of food to be had. At Semi- palatinsk we waited two days for a boat to go down the river, starting in the early morning of August 5, and reaching Omsk on August 7. The fast express on the Siberian railway carried us westward from Omsk at midnight, August 8. This joiirney furnished many entertaining incidents, some of which I have narrated elsewhere. It afforded continued opportunity for observations of geologic and physiographic interest, of which the most suggestive are here presented in classified rather than in narrative order, under such headings as mountains, glacial records, Tertiar)- basins, vallej-s with gorges and terraces, and lakes. The features of the mountains and the Tertiar}- basins do not bear directly on the work in hand. The other headings afford material of a kind that may, if sufficiently extended by further observation, suffice to determine a number of subdivisions of Quaternary time. On all these subjects, except the Tertiary basins, ]\Ir. Huntington's report on his journey south to Kashgar and west to Fergana in August and September contains important information supplementing that which was gathered while we were together through July. WE.'VTHER, CLIMATE, AND VEGETATION IN THE TIAN SHAN. The oppressive heat of the southern plains had already moderated at vSaiuar- kand and Tashkent. After leaving Andizhan the days were not uncomfortably warm, except for a few noon hours in the upper Narin Valley, and the nights were always cool or cold. Water froze near our tent at Son Kul on the night of WEATHER AND CLIMATE IX THE TIAN SIIAX. 71 Jul\- 8-9. Rain fell not infrequently between noon and night, for the most part from the mountain-made, overgrown cumulus or nimbus clouds, which drifted slowh- eastward, their cirro-stratus cover far outreachiiig the main cloud mass. Main- of the showers fell only on the mountains, leaving the open, inter-range depressions, such as the Alabuga and Narin valleys and the Issik Kul basin, dr)- and of subarid appear- ance. Thunder showers swept b\- while we were in the (western) Kugart \'alley, June 30, and while we were crossing the Kugart and Oi-Kain passes, July i and 2; hea\y rain and hail showers drifted over us at Son Kul, July 10. We wore long, black woolen waterproof cloaks (burkas) of the Caucasus, that protected us admira- bly while riding in the rain. The Chaar Tash range, ending eastsvard in the angle between the Alabuga and Narin rivers, fed a series of floating cumuli f July 6), which slowly dissolved as they drifted bejond the mountains. We saw a number of distant thunder storms o\-er the mountains by Issik Kul. The fair-weather days on this lake were characterized by clear sky over the water and by long rows of cumuli over the snowy Kungei and Terskei Alatau to the north and south. We were troubled with high wind only on July 17, when a dr}' gale from the west swept over the plain bj' Issik Kul ; and for a short time in the afternoon of August 2, when a furious dust squall from the west beset us as we rode into Semipalatinsk. The only climatic feature which our short excursion brought clearly forth is the contrast between the mountains and the deeper valleys as to rainfall and relative aridity. As already noted in the Kopet Dagli, a difference of elevation of a few thousand feet produced a marked difference in the appearance of the surface. \'egetation was scanty in June in the deeper interior \-alleys or basins of the Tian Shan at elevations of 7,000 feet or less ; it was abundant in the higher valleys above 8,000 feet. The cause of this contrast did not seem to reside mereh- in increase of rainfall with altitude, and in the protection of the inner valleys from the rain-bringing winds by the inclosing mountain barriers, but also in the direct excitement of rain-making processes on the mountain ranges and in the cessation or perhaps e\-en the reversal of these processes in the large, open valle\-s. The preceding paragraph tells of several examples in which the growth of thunder- shower clouds was intimately associated with moimtain ranges, thus suggesting their dependence on the ascending diurnal breezes on the mountain sides, as has often been noted elsewhere. In contrast with the mountain cloud masses was the prevailingly clear sky o\-er the open depressions, as noted in the Alabuga and Narin valle)-s and over Issik Kul ; and here a descending component of atmospheric movement should prevail to compensate for the ascending component where the cloud masses occur. Hence the open valle\s not only receive ver>- little summer rainfall, but they are swept over by air whose dryness has been increased b}- the descending component of its motion. Their descending component is not merelv that by which a wind should, after crossing a range, tuni do^^^lward into a basin. The descending component of this general origin must be largely increased by the local con\ectional circulation that is excited by the mountains. Thus the basins not onh- get little rainfall, but are parched by evaporation into the dr}-ing winds that settle upon them. The seasonal migration of the Kirghiz, with their herds 72 EXPLORATIONS IN TURKESTAN. and flocks, is an immediate response to the distribution of vegetation, as thus determined. The prevailing absence of trees is tlie most notable feature of the vegetation. There were open groves of poplars close b)- some of the streams, Ijut where the more important trails followed the valleys the trees had been unmercifully trimmed or felled for firewood, and few remained standing. In one of the branch valleys of the Alabuga a single large tree ser\'es as so notable a landmark that it is entered upon the large-scale Ru.ssian map. On our way from the Narin Valley up to Son Kid, we passed through fine groves of coniferous trees, but their occurrence was exceptional. Nothing of the sort was seen at similar altitudes when descending from Son Kul into the Tuluk Valley. Again, during our ascent into one of the south-opening vallej'S of the Kungei Ala-tau, north of Issik Kul, fine groves of conifers occupied the more shaded slopes of the side ravines. The line between trees and herbage was often verj- sharply defined. This was noted by Severtzof, who ascribed the general absence of trees to a recent change from a moister to a drier climate (1875, 66, 67); but it is difficult to believe that the prevailing absence of trees is natural on mountain slopes where flourishing groves are occasionally found. It seems more reasonable to ascribe the treelessness of the mountain sides to their long occupation by nomadic pastoral tribes, to whom pastures were of greater value than forests. It would be interesting, in this connection, to inclose and protect certain of the mountain tracts from grazing, and to plant them with tree seeds or young trees ; and it would be surprising if a thrifty growth did not result. It is also noteworthy that the absence of trees is not accompanied either by small rainfall or by barrenness on the mountain sides. Rains were abundant in the higher ranges in Juh', and gra.ssy herbage grew there luxuriant!)'. An interesting contrast in the relation of vegetation to insolation was noted in passing from the deeper valleys to the higher mountains. In the bad-lands of the Narin basin, at altitudes of 6,500 or 7,000 feet, the sunny slopes were prevailingly bare and minuteh' dissected, while the shady slopes were occupied by a sparse herbage and were of smoother form. On the high spurs of the Kungei Ala-tau, at altitudes of 10,000 feet or more, and above the tree line, the sunny slopes had the better cover of grass, while the shady slopes were relatively barren. In the first case, sunshine promotes aridity and exchides vegetation. In the second case, sunshine promotes snow-melting and favors vegetation. DEVELOPMENT OF THE TIAN SHAN MOUNTAINS. A number of the mountain ranges that we saw were of vigorous form, with sharp peaks and deei>car\'ed ^•alle}•s, in which it was impossible to recognize any trace of the original unsculptured mass ; but certain observations made in the central and northern ranges, near Lakes Son Kul and Issik Kul, and on the steppes that border the mountains on the north, led to the belief that the region had been verj' generally worn down to moderate or small relief since the time of greater defonna- tion, which probably occurred in the Mesozoic age ; that large areas of subdued or extinguished mountain structures are still to be seen in the low ranges and in the THE TIAN SHAN MOUNTAINS. 73 steppes north of the Hi River; and that the present relief of many of the higher Tian Shan ranges is the result of a somewhat disorderly uplift and of a more or less complete dissection of dislocated parts of the worn-down region. Mr. Huntington's report .shows the application of these conclusions to a large part of the central and southern Tian Shan. THE BURAL-B.\S-TAU. The first range that led to this belief was the Bural-bas-tau, which rises north of the Narin \'alle\- and southeast of Son Kul. Its name is taken from the Russian 40-verst map. Friedrichsen (1899) calls it the Mulda-aschu. We saw the range some 50 miles away as we were riding down the Alabuga \'alley on July 4 ; the Fig. 40. — The Flat-Topped Bural-bas-tau, looking Southeast. evenness of its snow-covered crest suggested that it nuist be a plateau-like mass of horizontal structure, amid its deformed neighbors. It was lost to sight after we had entered the Narin \"alley, and was not seen again until July 9, when we climbed the Kok-tal range northeast of Son Kul. It was there that figures 40 and 41 were Fig. 41. — The Flat-Topped Bural-bas-tau. looking South. sketched. The e\-enness of the plateau-like highland, all snow-covered at an estimated height of at least 12,000 or 13,000 feet, was most remarkable, and all the more so as our field-glasses now showed the range to be composed of massi\-e rocks, probably granites, such as are plentiful thereabouts. The highland has faint undulations, and slopes gently to the north and east. Great ravines, heading in glacial cirques, are car\'ed in its northern flank. The spurs between the ravines preserve their even crest for a short distance, but are then converted into sharp aretes. One ravine, longer than the others, cuts the highland obliquely. It reminded us of the Colorado Canyon in the Kanab plateau of Arizona, as we had seen it from the top of Mount Trumbull in the sunnner of 1902. One ravine-heading cirque, opening northward, seemed to head against another, opening southward, and there the even highland surface was reduced to a serrate ridge that sagged a little below the general level. The highland ascends gradiialh- westward, and in that direction its detached por- tions, with flat tops, are seen beyond encroaching \alleys; then, still farther west, these arc succeeded by peaks and ridges of ordinary fonn in the Dongxis-tau range south of Son Kul. 74 EXPLORATIONS IN TURKESTAN. There can be no question that the highland of the Bural-bas-taii was once part of a well-finished lowland of erosion, presumabh- a peneplain of subaerial degrada- tion. It must ha\e gained its present altitude with comparative rapidity, and in geologically modern time ; otherwise it would be more dissected to-day. When it still lay low, the lowland of which it was a part must have been much more extensive than the present area of the highland ; for lowlands can not be worn down on resistant crystalline rocks without the very general reduction of all neighboring and quiescent structures. It thus becomes probable, from the consideration of this range alone, that many neighboring ranges have shared its historj-, and if they do not all to-day imitate its plateau-like fonn, it must be that they were somewhat less worn down in the previous cycle of erosion, or, like the Dongus-tau, already more consumed (owing to greater uplift or to weaker structure) in the present cycle, or both. This conclusion did not long remain a matter of speculation only, for at Son Kul and around Issik Kul we found many other ranges that sujjported it. THE KOK-TAI. RANGE AND THE SON KUL BASIN. The steep-sided glacial troughs that we examined in the Kok-tal range north- east of Son Kid are eroded in a granitic upland of moderate relief that slopes toward the lake basin. The sloping tipland was continued east of the lake, where it gradtially descended to a broad granite floor, across \\liich the lake outlet has cut an open trench, 75 or 100 feet deep. All this granite surface is to-day suffering dissection and gaining stronger relief The lake outlet must fall rapidly in descending 3,000 feet to the Narin Ri\-er, and a deep gorge will in time be cut along its course. The side streams from the north will, therefore, intrench them- selves deeply, and the granite .slope between them will be converted into a series of .sharp spurs in the mature stage of the present cycle of erosion. The simple surface in which the glacial troughs and stream valleys have already been eroded is itself a surface of erosion, but it could not have been produced in its present attitude ; it must have long stood lower and more nearly level. Its present elevated and inclined attitude must have been gained by a warping uplift in modern geological time. We are, therefore, disposed to look upon the sloping upland as once having made part of the peneplain that is more clearly proclaimed in the highland of the Bural-bas- tau. The basin of Son Kid is probably the result of warping or faulting the same peneplain. The northern slope of the Kok-tal range descends rapidly into the valley of the Tuluk, and its slope is sharply dissected by man}- side streams. When seen from the moraines in the Chalai range, north of the Tuluk, the crest of the Kok-tal has a rather even crest line, much more even than the serrate crest of the Chalai range itself THE RANGES NEAR ISSIK KUL. The road through the gorges of the Juvan-arik gave us no sight of the mountain crests ; but when we entered the open Kach-kar basin, the long slope of the Alexander range ascended northward from the farther side of the basin, and its general appearance at once suggested block-faulting. This suggestion was con- THE RANGES NEAR ISSIK KUL. 75 Alexander FUinge, looking firmed b)- many features noted afterward. The south slope of the range had a hackly surface, due to the erosion of many small branching valleys among its \aricolored crystalline ledges ; but when seen in profile a few days later from the west end of Issik Kul, the smaller irreg- ularities of the slope were lost in a remarkably simple outline, sketched in figure 42. The crest rose above the snow patches of mid-July; one of its highest parts, isolated between two en- croaching valley heads, had an obliquely truncated summit in line with the long back (south) slope. The northeastern face of the range was much steeper and more sharply dissected by the side streams of the Chu. It was therefore concluded that the Alexander range is a faulted block of a peneplain, of which the former lowland surface is now uplifted, tilted to the south and moderately dissected, while the steeper northern faulted face is deeply carved in great spurs and ravines. The Kach-kar basin is apparenth' an aggraded area on the relatively depressed southern side of the block, as will be again considered farther on. Three small mountain masses (A, B, C, fig. 43), between the Alexander range and Issik Kul, had much the appearance of tilted and dissected blocks, sloping to the south and facing to the north. If this be true, their displacement ceased longer ago and their dissection has progressed farther than is the case in certain parts of the Wasatch range of Utah which I examined in 1902 ; for the spurs on the faulted face of the ranges by Issik Kul do not possess tenninal facets, and the ravines between the spurs on both the front and the back slopes have open mouths. On the other hand, the back slopes of these ranges still have general profiles of greater regu- larity than tliose of the Utah ranges that I have seen. This may be because the Issik Kul ranges were more smoothly worn down in the pre-faulting cycle than were the Utah ranges. The only sure indication of recent dislocation among these ranges was a fault scarp, 10 to 50 feet in height, more than a mile in length, and trending northwest- ward across the gravel fans at the northeastern comer of range B. It should be stated that this scarp was only seen at a distance of a mile or more ; but it was closely examined through a good field-glass from different points of view and in different lights. The manner in which it was crossed by the gullies radiating from the mountain ravines left no doubt in my mind as to its meaning and origin, A large fan, spreading into the Urta-takoi basin on the south side of the same range. ilftfe^ ALEX- '^ RANGE VSl LOFTY %mmi^j2^M SNOW COVERED :^My^ ^j^^^vvVllMlllrtoW'*"*^ -'^'^ -.. c, ALA-TAU 20 MILES ? Fig. 43. — Rough Sketch Map of the Ranges southwest of Issik Kul. jS EXPLORATIONS IN TURKESTAN. as well as many smaller fans at the base of other ranges, showed no signs of faulting. Their radial slopes were smooth and unbroken. The small range or block C, fig. 43, appears to be cut off from the larger block, B, b\- the gorge of the Urta- takoi (Chu) River. The post-road goes north through the gorge, but we turned eastward and followed the aggraded trough between ranges C and D, directly to the lake. A drs-stream bed, gathering all the wa.sh from the piedmont gravels of the much higher range, D, on the south, was pushed close to the base of the back slope of the smaller range, C, on the north, sometimes e\en undercutting the base of its spurs. The northern range was, where we saw it, composed of rough conglomerates and sandstones, dipping steep to the south, and to all appearance much older than the modern conglomerates of the Issik Kul basin. Their strike to the east-northeast ran obliquely to the trend of the range. The strata were obliquely truncated b\- the general back slope of the range, as in figure 44. The conglomerates and sand stones, generalh' dull-red on fresh surfaces, were so darkh' weathered with "desert varnish " that we at first took them to be basaltic lavas ; they were often cut by black Fig. 44.— Ideal Secrion from Range C to D, Figure 43, dikcs. The northern face of this range was looking east. , , i t^ much steeper than the southern. Range D, on the south, gave no conclusive evidence of block-faulting, for it was much dissected ; but its comparatively straight northern base-line and the great body of waste that has accumulated beneath it are suggestive of differential movements, with the appropriate consequences of degradation of the uplifted block and aggradation of the depressed block. A few knobs of rock rise tlnough the piedmont gravel slope. They may be interpreted as remnants of narrow blocks, on Gilbert's theory of faulting, or as remnants of a broader mountain mass on Spurr's theory' of compound erosion of the Utah-Nevada ranges. The Kungei Ala-tau, north of the west end of Issik Kul, is a dissected block- like mass with a plateau-like crest. It rises and becomes more and more dissected to the east. There is much evidence of subordinate faulting along part of its southern base, as will be more fully set forth in the chapter on Issik Kul. North of the middle of the lake this range is of well-developed Alpine form, with cirques and glaciers that are further described in the chapter on glacial records. It may here be noted that earthquakes, of no infrequent occurrence in the Tian Shan, are regarded by Mushketof (1890) as due to movement on fault lines along the base of certain ranges, the Alexander range being one. The shocks by which Vyemyi was destroyed on May 28, 1887 (O. S.), were ascribed by this observer to a fault along the northern base of the Trans-Ili Ala-tau. The shocks continued for about two years. Wosnessensky (1888) showed that they \-aried with the changes of atmospheric pressure, increasing with the occurrence of low pressure. We were told that Sazanovka, a Russian settlement on the north side of Issik Kul, was destroyed by an earthquake six years ago. THE NORTHERN RANGES AND STEPPES. 11 THE RANGES AND STEPPES OF SEMIRYETSHENSK AND SEMIPALATINSK. Our hurried northward ride from Vyemyi across the Seven-river and Seven- house pro\inces, above-named — one in Turkestan, the other in Siberia — to the cit^- of Semipalatinsk, allowed no opportunity for deliberate observation, yet it gave a sight of certain pliysiographic features that could be appreciated e\-en from a rat- tling tarentass (fig. 45), and which deser\-e brief record. The post-road crosses a broad plain, apparenth' loess-co\-ered and certainly very dust}-, north of the Trans-Ili Ala-tau, and gradually descends to a bridge across the Hi River at Iliisk. North of the river ledges appear and the surface rises more rapidly. The upland plain continues to the northwest, where we saw in the distance a narrow, rock-walled gorge, through which the ri\er flows to the desert bordering Lake Balkash. A solitary- monadnock- like mound rose above the broad plain near the gorge. Northeast of Iliisk low mountains of sub- dued fonn were crossed in the early evening. The ne.xt morning a western spur of the subdued Borochoro range north of the Kok River, by Tzaratziu post-station, presented fonns that suggested block-faulting, and that found no explanation in the structure of the cPiStalline rocks of which it was composed. It had a nearly even sky line, an abrupt southern face with simple base line, and short, steep ra\ines. The ri\-er flows through an open \alle\- by Tzaratziu, but enters and lea\-es the valle>- by narrow gorges. Farther northwest and north the relief decreases. It was hereabouts that we saw the first of the loess drifts, described above. F.g. 43.- -A Tarentass at a Station on the Post-road between Vyemyi and Semipalatinsk. Fig. 46. — Rough outline of the Dsungarian Ala-tau, looking south. On the third morning we had passed the western end of the Dsungarian Ala- tau, and saw it to the south of Arasan station at sunrise. Its sky line is notably even, although the northern flank is deeply carved, as in fig. 46. It gains greater height and greater irregularity to the east. Between Arasan and Abakumof sta- tions we crossed a branch of this range by an open pass at about 4,000 feet eleva- tion, an easy rise from the south being followed by a steeper descent for the better 78 EXPLORATIONS IN TURKESTAN. part of i,ooo feet to the north. Here one of the hind wheels of our wagon broke down, and we had leisure to look about while the postilion rode on for a new one. The branch range was composed of slates, with \-ertical clea\age striking abotit east-west. Its sunnnit was a broadly-rolling upland of gentle relief, while sharj)ly- cut ravines were gnawing into its steep northern slope. When we had ad\anced some miles across the broad plain north of the range, its upland was seen rising gradually eastward in a warped slope. Its northern face was finely carved in sharp spurs and ravines. Figure 47 is hardly more than a diagram of these features, verj- hastily sketched, yet it presents their essential character. Nothing but uplift and partial dissection of a peneplain can account for so remarkable a contrast of old and young fonns. The plain continued till nightfall, with small change of fonn. The fourth da)- opened on a broad, genth- rolling steppe, stretching from Ashi- bulak to Arganatinskaj-a. Occasional outcrops showed at first a crj-stalline rock, then a belt of slaty limestones, and finally a series of much disturbed slates. Gray loess-like silts, with angular rock scraps, occupied the shallow depressions. A lake a few miles long was seen to the east. The steppe, as a whole, was sometimes rather Fig. 47. — Rough Sketch of a Range near Abukumof Station, looking south. too uneven to be called a peneplain, although certain areas fully justified that term. The sky line was generally of moderate irregularity, and the galloping pace of our horses on a road that turned but little for mile after mile testified to the gentleness of the slopes. The low-arching hills seldom deser\'ed to be called monadnocks, except for a few knobs that rose over a broad swell in the belt of limestones and slates. Etj-mologists, who have not hesitated to give our language the word "antepenult," as well as "penult," might name a region in this stage of degradation an "antepeneplain"; but physiographers do not yet recognize the need of so elaborate a term. There was the appearance of a general and gradual rise northward, until we lost sight of the upland by descending a narrow and winding valley worn in the contorted and jointed slates by a north-flowing stream. When the valley had gained a depth of about a hundred feet it suddenly opened upon the broad plain that stretches east- ward of Lake Balkash. On looking back toward the upland we saw it descend to the plain by a low, regular, but somewhat dissected escarpment. A gentle slope of slaty gravel stretched a short distance forward from the escarpment to a claj- plain, varied with dust}- dunes and marshy swales overgrown with reeds. The road was ver}- bad here in sand or mire. Nothing that could be called an old shoreline of Balkash was noted. Toward evening we saw some low hills ; the plain became grav- elly, and low mounds of angular slate waste suggested that the rock was not far below the surface. The road at once improved, and in the night we had the best sleep of our posting trip. THE STEPPE OF SEMIPALATINSK. 79 All of the fifth day was passed on a rolling steppe (fig. 48). In the morning, near Sergiopol, the country rock was granite, but the relief was small. The up- lands stretched broadly between the shallow valleys. Once the road led through a rather narrow transverse \alley in a low swelling ridge. A few of the ridges might be called mountains in a flat country, but they hardly deserve so strong a name ; even the highest of them was of subdued fonn. Near Arkut station we saw the only sharp form of the da}'. A ragged ridge, 300 or 400 feet high, was silhouetted against the sunset sky. It may have been a dike of more resistant rock than that on either side. The peneplanation of the region improved in the final 40 miles of the road on the sixth da)-. In the morning some of the broad ridges of steep-dipping slates and slaty limestones, trending east and west, were from 300 to 500 feet over the inter- Fig. 48. — The Rolling Steppe north o{ Sergiopol, Semipalatinslc. vales, but the latter were 2 or 3 miles wide. In the afternoon the relief decreased ; low mounds, irregularly distributed, were strewn with angular scraps of quartz. The sky line was here so even and its occasional hills were so faint that sketching could do little justice to it. For some miles before reaching Semipalatinsk the country seemed perfectly le\'el. The Irt}'sh River at Semipalatinsk occupies a good part of a valley floor that is from half a mile to a mile wide, and about 30 feet below the surrounding plain. The valley sides disclose \-ertical beds of slate and sandstone, with strike about north ' and south, evenly truncated by the surface of the plain and veneered with sand and gravel, in which occasional boulders up to 2 feet in diameter were seen. This district shows as fine an example of a low-lying peneplain as I have ever seen. The vigorous Irtysh has begun the dissection of the plain ; but a few miles from the river the small streams still lie on the floor of the broad hollows between the low ridges. 8o EXPLORATIONS IN TURKESTAN. ORIGIN OF THE EXISTING RANGES OF THE TIAN SHAN. When the features here described from Son Kul to Seniipalatinsk are con- sidered in a broad way, they suggest many reflections of interest in theoretical geolog}-. The extended occurrence of surfaces of small relief, indifferent to the rock stnictures which they tnincate, implies a long cycle of uninterrupted degra- dation, continued past late maturity, even to old age. The earlier form of the eroded region may well have been motmtainous ; witness the steep-dipping or vertical strata seen at various points, as well as the occurrence at the surface of rocks whose origin nuist have been deep-seated, like granites. The agency of erosion was not the sea, of whose presence in modern geological time the region gives no indication ; nor was it the lateral swinging of rivers, as Philippson (1898) has supposed for the plains of central European Russia, for the eroded surface fre- quently possesses a minor relief that is inconsistent with such a process of planation. The various processes of subaerial erosion, of which the swinging river is but one, best explain the widespread peneplanation here obser\-ed. Although the peneplain was not observed by any means continiiously from Son Kul to Seniipalatinsk, there is good ground for thinking that it once stretched as an almost continuous lowland, interrupted only by residual ranges, over all this distance, and indeed over still greater distances ; for it is not reasonable to believe that a cycle of erosion which sufficed to develop a peneplain even on granitic rocks should find other rocks resistant enough to maintain a great relief, unless, indeed, tiplift came to aid resistance. There is, however, no direct evidence of uplift during the cycle of peneplanation. Where great relief occurs in the region to-day, it is accompanied b}- the suggestion of uplift after peneplanation — or, at least, after a ver}- late mature stage of erosion — had already- been reached. Witness the peaks of the Dongus-tau below the westward prolongation of the highland surface of the Bural-bas-tau, or the peaks of the central Kungei Ala-tan below the eastward prolongation of the even crest in the western part of the same range. If certain ranges do not to-day present such evidence of a former c3-cle of erosion, it is more consistent with the general features of the region and with the general principles of mountain sculpture to suppose that they have lost the e\-idence than that they have never had it. This conclusion, based on my own observations, is strongh- supported b)' the observations made independently by Mr. Huntington and presented in the report on his Kashgar journey. He describes large highland areas of the Tian Shan between Issik Kul and Kashgar as broadly uplifted peneplains, here and there bearing subdued mountains, the whole being in process of revived erosion. He therefore names the region " the Tian Shan plateau." It is, as he happily phrases it, not actually but only potentially mountainous. Previous observers hsLxe recognized the plateau-like highlands of the Tian Shan, but most of them do not seem to have recognized their meaning. Roborovsky, reporting on an expedition led by Piev- tsoff" in 1889, briefly describes a high plateau, between Issik Kul and the Tarim basin, called the Syrt, 100 miles wide, and at an altitude of 10,000 or 11,000 feet. " Scattered over it are separate mountain groups and ridges, running east and west" (1890, 23). St Ives, who crossed this region later, says that it is an immense PENEPLAINS IN THE TIAN SHAN. 8l plateau, known to the Kirghiz as the " Arpa," 3,000 meters in altitude, overlooked by serrated ranges and traversed by low hills (1900, 125). Alinasy, who traveled somewhat farther east in 1900, gives "syrt" as the Kirghiz name of the plateau, which he describes as occupied by highland meadows (1901, 254). In Friedrich- sen's thorough review of all that has been written about these mountains, there is no clear statement concerning the plateau-like quality of the inner region ; but it may be inferred from the statement that the general law of vertical relief in the Tian Shan is an increase of absolute height accompanied by a decrease of relative height in passing from north to south (1899, 209). In Friedrich sen's account of his own exploration, however, there is an explicit statement. He trav- ersed the syrt or highland southeast of Issik Kul at an altitude of 3,000 meters, and found it to be an extended, gently inclined plain in which the granite, gneiss, and steep clay slates are broadh- tnmcated, above which the snowy ranges (4,000 meters) rise with relatively small relief, and below which deep, canyon-like valleys are eroded by the Sary-jass River and its tributaries. He recognized it to be a " Denudations- flache" or peneplain (1903, 99). The deformation that the great peneplain has suffered in that part of its area which is now mountainous seems to have involved late or post-TertiarA- movements of relativel)- local uplift, as in the Bural-bas-tau ; or of much broader uplift, as south of Issik Kul ; or of moderate warping, as in the branch of the Dsungarian Ala-tan ; or of block faulting and tilting, as about the west end of Issik Kul. This is consistent with the account of the Tian Shan furnished to Suess by Mushketof, in which it is stated that the earlier deformation of these mountains was not before the Trias, and that the final configuration of the ranges was given in post-Tertiary- time. The latter statement is based on the occurrence of Tertiar}- strata at great altittides, no mention being made of the evidence from peneplanation (Suess, 1897, i, 619). It is noteworthy that there is no general evidence of crustal compression in the later defonnation that the Tian Shan seems to have suffered. True, the vertical strata and the \-ertical cleavage of slates impl\- that the region suffered a strong compression in some time previous to peneplanation ; but the existing Tian Shan ranges, so far as they are described, are not the result of that ancient compression. They are due to a later system of defonnation that gives little evidence of com- pression. The contrast between the earlier Tian Shan s)stem and the present ranges is similar to that pointed out by Ciilbert between the Appalachians and the Basin ranges of Utah and Nevada : In the Appalachians corrugation 'has been produced commonly by folding, exceptionally by faulting; in the Basin ranges, commonly by faulting, exceptionally by flexure. The regular alter- nation of curved synclinals and anticlinals is contrasted with rigid lx)dies of inclined strata, bounded by faults. The former demand the assumption of great horizontal diminution of the space covered by the .disturbed strata, and suggest lateral pressure as the immediate force concerned; the latter involve little horizontal diminution, and suggest the application of vertical pressure from below. * * * In the case of the Appalachians the primary phenomena are superficial; in that of the Basin ranges they are deep-seated, the superficial being secondary; that sucJi a force as has crowded together the strata of the Appalachians — whatever may have been its source — ^lias acted in the ranges on some portion of the earth's crust beneath the immediate surface ; and the upper strata, continually adapting tliemselves, under gravity, to the inequalities of the lower, have assumed the forms we see (1875, 61, 62). 82 EXPLORATIONS IN TURKESTAN. It therefore does not seem advisable to adduce the Tian Shan ranges in ilhistra- tion of the direct action of a " tanefcntial movement," as has been done by Sness (1897, i, 619) on the basis of Mnshketof's description. It is tnily possible that compression may have had .some share in producing the existing disordered attitude of the mountain blocks, for folds of late or post-Tertiary date occur in the Narin fonnation, as is further stated below ; but the share that compression had in raising the block ranges is so problematic that it should not to-day be accepted as an established fact, and still less should it be emploj-ed as the base of further theoretical considerations. THE BEARING OF THE TIAN SHAN RANGES ON THE THEORY OF HORSTS. The Bural-bas-tau and its fellows deser\'e special consideration in connection with the theor)' of the origin of horsts, or upstanding crustal blocks, as set forth by Sness, who regards such horsts as stationary parts of the earth's crust, with respect to which the surrounding lower land has sunk (1897, i, 263, 774, 777, 782). The evidence for this conclusion is chiefly that "we know of no force whatever that is capable of uplifting from below, between two plane surfaces, large or small mountainous masses, and of maintaining them pennanently in such a situation, against the action of gravity" (1897, i, 782; also 775). This conclusion and the reason for it both seem to me to place too high a value upon what we do not know. It is, of course, conceivable that horsts have stood still while the surrounding lands have sunk down, but it is also conceivable that the horsts have been raised, while the surrounding lands have remained stationar)- ; that the horsts have risen and the surrounding lands have sunk ; and that both have risen, the horsts more than the rest, under conditions suggested by the citation from Gilbert, above made. The last supposition seems eminently applicable to the Tian Shan. Direct observation seldom, if ever, furnishes evidence by which one can choose among these various mechanical possibilities. In the case of the Tian Shan there is certainly not enough now known concerning the attitudes of the faxdt planes b}- which various blocks are divided to make it worth while to discuss this recondite aspect of the problem. As to the way in which blocks of the earth's crust might be dislocated into irregular attitudes, we can conceive of many theoretical processes, every one of which is permissible in the presence of our abimdant ignorance of the constitution and behavior of the earth's interior. It seems, therefore, unsafe to-day to exclude all other processes than direct-acting gravity from a share in the production of horsts. Forces of uplift are still worthy of consideration. In such a problem it seems better to open the mind as freely as possible to reasonable speculation, rather than to restrain its inventive powers. Deep-seated movements of the earth's core, possibly due to deep-seated compression, may cause local internal up-swelling, over which the heavy- lying crust is broken and irregularly jostled in mountain blocks. It is this sup- position that is entertained in Gilbert's suggestion as to the origin of the Basin ranges of Utah and Nevada, above cited ; but neither the supposition of local jost- ling and uplift within a surrounding region of relative stability, nor the counter THE UPLIFT OF THE TIAN SHAN. 83 supposition of local stability within a surrounding region of depression, can to-day- be regarded as established for the Tian Shan. It may, however, be pointed out that Suess's view as to the stability of horsts involves extreme measures of the diminution of terrestrial volume. When the highland of the Bural-bas-tau is recognized as a fragment of a central Asiatic pene- plain, it must be recognized as having once stood not much above sea level ; and if 8,000 or 10,000 feet out of its present total altitude of 12,000 or 13,000 feet result from the depression of the Siberian part of the Asiatic peneplain, then all the oceans and all the continents of the world must have gone down with the Siberian area, except for such highlands, if any, that held their own with the Bural-bas-tau. This seems to call upon a very large mechanism to produce a relatively small result. Not only so. The plateau of northern Arizona, in which the young canyon of the Colorado River is cut, owes its altitude, by Suess's theor)-, to the depression of the Great Basin region to the west of the plateau ; but this plateau is also a pene- plain, as Dutton has shown, hence not only the lower land to the west of it went down, but again all the oceans and all the continents as well, and this time the Bural-bas-tau with the rest — unless, indeed, the depressions of the surrounding regions, by which the Bural-bas-tau and the plateaus of northern Arizona were left in relief, both occurred at the same time. In the latter case we have onl}' to con- sider one of the many other more or less dissected peneplains, that of southern New England, for example; all of these can not possibly have been left standing by a single movement of depression, because their present stage of dissection is so unlike. It thus appears that, according to Suess's theory, the diminution of the the terrestrial radius at any point ma}- be measured (if we neglect the altitude above sea level at which peneplains are formed) by the sum of all the non-synchronous depressions b}- which the horsts of peneplains have been left in relief, Diinns the altitude that a peneplain (if one occurs) happens to have at the point of measurement. As said above, there may be no evidence by which the theory that leads to this conclusion can be absoluteh' proved or disproved, but the conclusion is a curi- ous one, and as long as it is ba.sed chiefly on our ignorance of the earth's internal mechanism, it can hardh- have general acceptance. It does not appear clearl\- from Suess's work whether he recognizes the necessity of this conclusion or not, for he does not seem to take account of the altitude that the surfaces of horsts had with respect to sea level before they were isolated by dislocation. Indeed, his study of the Face of the Earth takes relatively little account of erosion. One finds, how- ever, an indication of the acceptance of great changes in sea level in such sentences as the following: "I hope to be able to show that there is ground for correcting more than one general!)- accepted opinion as to the position of the le\-el of the sea at epochs anterior to ours" (1897, i, 782). It will be a matter of interest to see how far problems of this sort are treated in the final volume of Das Autlitz der Erde. 84 EXn.ORATTONS IN TURKESTAN. GLACIAL RECORDS IN THE TIAN SHAN. Russian explorers of the Tian Shan liave discovered many glaciers in its hijifher ranji^es and have mentioned the occurrence of al^andoned moraines lower down the vallejs, but as far as I have read there has been little study given to the subdivisions of the glacial period. To this latter subject, therefore, we ga\-e chief attention while we were in the higher mountains. The strong ranges between Issik Kul and Kasgliar contain a much fnier development of abandoned moraines than any of the ranges that we saw between Andizhan and Issik Kul. The problem of succes- sive glacial epochs is, therefore, much more fully treated in Mr. Huntington's report than here. Fig. 49.— The Chalai Range from Kum-ashu Pass in the Kok-tal Range, looking norlh; a large old Moraine advances to the left, behind the dark spur. The crest of the Chalai Range is dimmed by clouds. MORAINES NEAR SON KUL. Although we recognized the occurrence of glacial cirques at a distance in several high ranges, the first moraines that we came upon were in the mountains south and northeast of Sou Kul. Those in the north-opening valleys of the Uougus- tau range, south of the lake, were of small size at altitudes about 10,500 feet ; the range summits seemed 1,000 or 2,000 feet higher. The glaciated troughs on the southwest side of the Kok-tal range, northeast of the lake, 8 or 10 miles from its outlet, were recognized in the distance. On riding and walking up to them in the afternoon, we found a well-defined moraine, with mounds and bowlders, kettles and GLACIAL RECORDS IN THE TIAN SHAN. 85 ponds, crossed bj- a cascading stream at about 10,500 feet, in a valley that had received the confluent glaciers from two troughs. The glacier from the larger trough must have been 2 miles long. In the next trough to the west, the glacier seems to have been smaller. No strong moraine was seen there. Further down the valleys there were smooth hills which we did not at the time take for moraines, but in the light of what was seen later, I am now disposed to regard them as weathered and rounded morainesof early origin. It was on the sides of these smooth hills that we saw the old irrigating canals, to be described in a later section. The glacial troughs, higher up the mountain, were of wide open, steep-sided, U-shaped form, eroded in the slanting granite highland already described. When descending from the Kum-ashu pass in the Kok-tal range, we .saw to the north a large moraine beneath a glaciated vallc)- of the Chalai range (Jumgal- tau on Stieler's map, sheet 62), beyond the Tuluk-su (fig. 49). The glacier that made this moraine must have been 3 or 4 miles long, heading in three cirques beneath the sharp peaks and aretes. On going up to the moraine the next morning, we .saw a second and larger one, which j\Ir. Huntington examined, about 2 miles Fig. 50. — Moraine in the Tuluk Valley, looking west. to the west. In both cases the large moraines were of well-rounded forms, with few surface bowlders and without distinct mounds or kettles, and the stream that issued from them had a well-opened valley with something of a graded and flood- planed floor. Moreo\er, the main ;\alley seemed to ha\e been significanth- deepened by the Tuluk-su since the moraine was laid in it ; and certainly some of the spurs on the south side of the main vallej- had lost their ends by the undercutting of the Tuluk, which the moraines had pushed against them, as shown in fig. 50 ; but the facets thus eroded on the spurs had roughly graded slopes, thus indicating that a considerable time had passed since the undercutting began. The other valley-side spurs showed no such facets, but tapered down to the valley floor. Within each of these large weathered moraines we found smaller moraines of much sharper and fresher form (fig. 51) ; their irregular mounds and ridges strewn with bowlders, their kettles holding small ponds, and their streams cascading in narrow courses. The youngest moraine ended about in line with the north rock wall of the main valley. This seemed to be a moraine of recession from a larger group of more advanced morainic loops. The time inter\'al of the retreat here indicated must have been short compared to the time that has elapsed since the larger moraine was formed. 86 EXPLORATIONS IN TURKESTAN. MORAINES IN THE TERSKEI ALA-TAU. When we reached the southwest shore of Issik Kul (July 14), the snowy summits of the Terskei Ala-tau were seen to the south ; so we crossed the outer, lower ranges from the delta to the upper valley of the Ula-khol, and there at once came upon an interesting group of moraines. The first moraines seen (M, fig. 43) were in a longitudinal valley at the northern base of the Terskei Ala-tau, about 3 miles to the southeast of the head of the Ula-khol gorge in the outer range. They had been formed by a glacier or Fig. 51. — A Young Moraine within the Old Moraine in the Chalai Range, looking north. glaciers that descended northward from the Kashga and Tnra side valleys, and stood at an altitude of somewhat over 7,000 feet. Their Iiills were delicately rounded ; the streams had eroded open-floored valleys acro.ss the morainic belt ; no undrained basins remained ; some hillocks were isolated, as if the valley-floor gravels had been aggraded around them. The materials of the moraine were, as a rule, unweathered, but we found in fre.sh-cut banks a few stones decomposed to a friable condition. About 2 miles to the south, and at an estimated elevation of between 8,500 and 9,000 feet, another moraine was seen in the Kashga \'alley. This was judged to be much younger, as seen in the distance, because the stream had cut onl)- a narrow trench through it. GLACIAL RECORDS IN THE TIAN SHAN. 87 In the afternoon of Jtily 16 we went 8 or 10 miles southwest of the head of the Ula-khol gorge, following the main stream west and south into the moimtains, and hoping to reach the valle}-s beneath the highest peak that we had seen from the lake shore ; ])Ut it proved that we were not far enough west ; and that bane of reconnaissance work, the lack of time, prevented our going farther. We found, however, at the mouth of a branch valley from the southeast a large, rounded morainic mass, similar in fonn and apparent age to those we had seen in the Tuluk Valley. A younger moraine was seen farther np the glaciated trough, in whose steep southern wall two hanging cirques opened. A terrace occurs in the main valley in association with the larger moraine. It was continued upstream as far as we could see, and there it was a hundred or more feet above the stream. It was distinctly traceable for half a mile down the valley, though with rapidly diminish- ing height in that direction ; farther down it was preserved only in small reinnants, and no signs of it were found in the longitudinal valley. Aggradation of the terrace seems to have been contemporaneous with the growth of the moraine, and the trenching and removal of the terrace with the weathering and rounding of the moraine. The moraine is thus doubly shown to be of considerable antiquity. This is confinned by finding that the terrace floor has been aggraded by wash from the moimtain sides, so that it now has a distinct slope toward the valley axis, instead of only a slope down the valley, as is habitual with young terraces. Two other old-looking moraines were seen ; one of them up the valley to the southwest, the other up a branch valley to the east. MORAINES IN THE KUNGEI ALA-TAU. As the Kuugei Ala-tau rises eastward along the north side of Issik Kul, the even crest line with which it begins is more and more dissected. Before the middle of the lake is reached the range has gained sharp Alpine fonns. A glacier was .seen high up among the summits, from near Tur-aigir station ; and a few miles north of Choktal station there seemed to be a moraine lying somewhat forward from the mouth of a valley, on the upper part of the piedmont slope, about 1,500 feet over the lake, or at an altitude of 6,700 feet. Further reference will be made to this moraine in connection with Lake Issik Kul. Severtzof mentions what he takes to be a moraine lying on "lake beds" on the south side of Issik Kul (1875, 32). The ascent from the Russian village of Sazanovka, near the lake shore, north- ward toward Sutto-bulak pass, in our unsuccessful attempt to cross it, carried us past what seemed to be an old, dissected moraine on the east side of the Ok-su Valley, at an altitude of 7,000 feet. Farther up a branch valley we came to a well- defined moraine whose lower end stands at about 9,000 feet, and whose western lateral ridge is 200 or 300 feet high. It is rather sharply trenched by the valle)- stream. The glacier that made this moraine nuist have been at least 3 miles long. We followed the vallc)- nearly to its head in our cfibrt to cross the pa.ss, .seeing a niunber of cirques on either side, inclosed by sharpened aretes (fig. 52). A small glacier occupied the head of the valle\- for half a mile or more at a height of about 88 EXPLORATIONS IN TURKESTAN. 11,300 feet. A small recent moraine lay about 300 feet forward from the end of the glacier ; a larger one, holding a .small frozen lake in its hollow, wa.s a half mile farther forward. There was too mucli snow on the ground just in front of the glacier to judge whether it was advancing or retreating at the time of our visit. SUBDIVISION OF THE GLACI.VI. I'ERIOD. The few exam])les above described of moraines of different ages suffice to suggest, but not to demonstrate, a subdivision of the glacial period, as it affected the Tian Shan Mountains. The many additional examples of more complicated series of moraines in the valleys below tlie higher ranges south of Issik Kul, afterward Fig. 52. — Snowfield below Sulto-bulak Pass in ihe Kungei Ala-tau, looking southwest ; a Cirque in the background. examined by Mr. Huntington, were fortunateh' more explicit in their testimony, and leave no doubt that the glacial period there, as elsewhere, was not a single climatic epoch, but a succession of epochs, and that the different epochs were of different intensities. It is important, as Mr. Huntington points out in his report, to bear in mind that the actual succession of glacial epochs was in all probability more complicated than the exi.sting records directh' indicate. It tnily seems po.ssi- ble, in our present ignorance as to the cause of glaciation, that four or five glacial epochs of progressively decreasing intensitv and duration might constitute the whole of the glacial period; but it is eminently prolxible that the first epoch was not the severest one, and that the record of earlier epochs of small intensity might be destroyed by the work of later and more intense glacial epochs. We therefore GLACIAL EROSION IN THE HIGHER RANGES. 89 have again a case, like the one already considered in connection with the terraced valleys of the Kopet-Dagh, of a series of decreasing maximum records, before and between which a number of minimum records ma}- have been made, only to be destroyed by the next stronger record. The preservation of four or five records makes it probable that the total number of glacial epochs in the Tian Shan was as many as six, eight, or ten. We fully concur with earlier observers to the effect that there are no indica- tions of general glaciation in the region that we crossed. GLACIAL EROSION IN THE HIGHER RANGES. This excursion across the Tian Shan gave me the first opportunity of seeing high mountains since reading Richter's Geomorphologische Untersuchnngen in der Hochalpen (1900). I therefore gave especial attention to the form of the mountains to determine how far Richter's thesis holds good as to the action of glaciers in sharpening the peaks and crests by causing the retreat of cirque walls. There was repeated occasion to test the thesis, and it seemed to hold good in every case. The Kugart pass, over 10,000 feet in altitude, and with the higher summits of the Fergana range on either side, presented no sign of glaciation. It is possible that some cirques occur not far to the southeast, but clouds covered the mountains too heavily in that direction at the time of our crossing to make sure. All the mountain forms by the pass were the result of the normal processes of erosion. The ridges were all dominated by the down-slope lines of creeping and washing ; and all the down-slope lines, decreasing in declivity as they were followed, combined in an elaborate branch-work system, adjacent lines alwa}-s meeting in accordant grade at their innumerable points of junction. In other words, the ridges were maturely dissected. As seen in profile, the down-slope lines had relatively little variety. Except for a small convexity near and at the crests, they were concave to the sky, and were systematically of decreasing slope downward through all their length, from mountain top far down the valley. This was particularly true for the stream lines of the many ravines which gather water and waste from the sides of their inclosing spurs, and which were prevailingly graded along their courses. It was true, also, to a remarkable degree for the waste-stream lines on the spur slopes, which were broken only by scattered outcrops of the stronger rock masses, and then only to a moderate amount. Here and there patches of hackly, ungraded ledges stood forth, not >et reduced to order; but on the whole the graded down-slope lines were remarkably well developed. The variety of these lines was shown in their plan rather than in their profile, and even in plan their variety is sj-stematic. The stream lines branch over and over again, as they are followed uphill, and the spurs are split repeatedly by the large and small ravines that fork beneath them ; but that is all. When the mountains are looked at hastily their variety of form seems confused, but when the fonns are more patiently analyzed their \-ariety is seen to result almost entirely from small changes on a simple scheme, and even,' element of form finds its explanation in the processes of nonnal erosion carried to a mature stage. 90 EXPLORATIONS IN TURKESTAN. The crest lines of the nonnally carved mature ridges are rather sharp and somewhat serrate. The slight convexity of the slope lines as they reach the crest shows that those processes of weathering in which changes of volume act nearly nonnally outwards from the weathered surface there have a relati\-el}- large share, along with gravitative down-slope washing, in the reduction of the mountain mass. This systematic coml)ination of nonnally eroded fonns was seen not only about Kugart pass, but in various other ranges, and in var)'ing degrees of develop- ment; but many of the liigher ranges exhibited fonns of another kind, imposed, as it were, upon the nonnal fonns of the valley heads ; and as these additional fonns were, in all cases where they could be closely examined, sj'stematically asso- ciated with moraines, they may at once be ascribed to glacial erosion and called glacial fonns. The glacial fonns are no novelty ; they are well known in other mountains. They are described here merely to show how systematically they repeat the features of similar fonns seen elsewhere. Their most significant features are as follows : They occur at great altitudes, such as 8,000 feet, in ranges that rise to still greater altitudes, such as 12,000 feet or more. They are independent of rock structures. When considered in profile they involve a double change of slope from that of nonnal fonns. If ABC (fig 53) represents a nor- mal slope, a glaciated slope, DEB, is steeper than nonnal in the upper part, D E, and less steep than normal in the lower part, E B. The steeper upper slope, D E, may be sunnounted by a less steep slope, A D, or it may rise directly to the crest line. When two such slopes meet, back to back, the crest is an unusually sharp and serrate arete. The lower slope, E B, may be hollowed to a basin form. When considered in plan, the glacial forms are simpler than the nonnal fonns that they have replaced, for they involve the substitution of a single broad-floored concave fonn for a number of inter- locking ravines and spurs. When two simple fonns of this kind are associated, the smaller one may open its floor in the wall of the larger one, so that the two floors do not join at accordant grade. Glaciated valle}' heads are so well defined that they have received a special name from mountaineers in different countries — cirque and kar in the Alps, botn in Norway, rMm in Wales, corrie in Scotland. All these features have been abundantly described by various writers — Bohm, Richter, De Martonne, Marker, Johnson, Gannett, Gilbert, L,awson, to name no more. Fig. 53. — Profile of a Cirque at the Head of a nonnal Valley. Fig. 54.— Cirque in the Kalkagar-tau. CIRQUES IN THE TIAN SHAN. 91 V. Forms of the kind thus characterized are not to be accounted for by the theory of normal erosion, and are not found where normal erosion has acted alone. They may, however, be accounted for by means of reasonable assumptions as to glacial action, and they occur, so far as is known, only in mountains that are otherwise proved to have been glaciated. Their occurrence may therefore be taken in evi- dence of the verity of the reasonable assumptions by which they are explained; all the more so because the process of glacial erosion is not open to direct observation, and because there are many different opinions as to its rate, method, and amount. For these very reasons it seems warrantable to determine the process rather by the forms that follow from it than by the little that can be seen of it in actual operation. The different glacial ranges of the Tian Shan that we saw either close at hand or in the distance afforded repeated examples of nearly every feature above named as characteristic of glacial action. Mention has already been made of the snowy range seen to the south of the Fer- gana basin, where our field glasses showed numer- ous cirques crowned with sharp peaks and aretes, and opening forward into trough-like valleys with over-steepened basal walls. These forms were as typical of strong glacial erosion as any that I have seen in the Alps. It was a surprise that features of this kind could be distinctly recognized at dis- tances of 30 or 40 miles, }'et we were persuaded that their identification was safe. We had a similar experience when looking from the Alabuga Valley at the Kalkagar-tau, some 30 miles to the south. Several of the cirques there noted are shown in figs. 54 and 55 as sketched through a field glass. All of these cirques are continued downward by narrow, steep-pitching normal valle>-s, with respect to which the cirques would have to be explained as the product of an earlier cycle of erosion if they were not admitted to be of glacial ori- gin. But if the open cirques were regarded as of normal origin, the mountain summits above them ought to be rounded fonns, while as a matter of fact they are as a rule singularh' sharp and serrate. Either fonn alone might be explained without recourse to glacial erosion, but the combination of the two fonns, sharp peaks and open val- leys, is believed to find explanation only by the special process of glacial erosion. While we were crossing the low ranges south of Issik Kul on July 16, a number of cirques and troughs were seen high up in the Terskei Ala-tau to the south and southeast. Some of the cirques opened on the walls of the larger troughs in true hanging-valley fashion. One of the troughs showed with remarkable Fig. 55. — Cirques in the Kalkagar-tau. Fg. 56. — Cirque near Sutto-bulak Pass, Kungei Ala-tau. 92 EXPLORATIONS IN TURKESTAN. distinctness the significant feature of over-steepened lower walls. All the cirques were associated with sharpened peaks and aretes. Two cirques, hanging over a glaciated trough, have already been mentioned in connection with the moraines on the headwaters of the Ula-khol. Similar features were seen farther east in the same range when we examined it a few dajs later through our glasses from the north side of Issik Kul. Cirques, needle peaks, and sharp aretes were well developed in the Kungei Ala-tau by the Sutto-bulak pass. One of the cirques opened in the side wall of the main valley several lunidred feet above its floor, as shown in fig. 56. Its floor must have been at an elevation of about 10,000 feet. The characteristic as.sociation of these various glacial forms in the higher ranges and their .striking contrast with forms of normal origin in the lower ranges was a suggestive lesson in mountain sculpture. THE NARIN TERTIARY BASIN. After crossing the open pass that separated the basin of the (eastern) Kugart from that of the Makmal, w-e found ourselves in a basin of partly consolidated conglomerates, sandstones, and clays, which was continued eastward down the Alabuga Valley, and whose end was not reached where we forded the Narin River and crossed the mountains on the way to Son Kul. Although no fossils were found Fig. 37. — General Cross-section of the Narin Formation, looking east. in the strata of the basin, we regarded them as of Tertiary age from their resem- blance to the Tertiaries of the Rocky Mountain region. The most noteworthy features of the Narin fonuation are as follows. THE PERIOD OF DEPOSITION. The basal beds of the formation were seen along the southern border of the Chaar Tash range, at the headwaters of the Makmal. They lay unconformably on granites and limestones. The surface of contact was of small relief, as far as could be judged b}' the continuity of the outcrops of the basal Narin beds along the mountain side. The formation consists of muddy conglomerates, bright red in color in its lower and marginal part, and of grayish clays, sometimes banded with red, toward the middle of the basin ; it includes a series of salt and gypsum beds in the lower members of the central area, as revealed there in a strong anticline. The stratifi- cation of the conglomerates and sandstones is variable and irregular, and cross- bedding was common. The stratification of the clays is often remarkably regular ; but in many sections of all these beds, toward the center of the basin as well as near the margin, lenses or " channel fillings " were of common occurrence. These THE NARIN TERTIARY BASIN. 93 were taken as evidence of a fluviatile origin of the deposits as a whole, while the salt and gypsum deposits, with tlieir associated clays in the lower central beds, were taken to mark a shallow central depression without outlet, sometimes holding a bitter lake, sometimes sheeted over with playa muds. The thickness of the whole fonnation must amount to thousands of feet. As in many other basins of hea\'y deposition, the basin floor, originally a land surface, must have been depressed thousands of feet, so that it in all probability lay below the sea-level. Hence, as far as crustal movements are concerned, the Narin basin is perhaps as noteworthy as the Dsungarian basin, at the east of the Tian Shan, in which the land surface to-day is below sea-level. The unusual feature of the latter basin may not be so much the depth of its depression, but the absence of sufficient waste or water-filling with which to fill it to a more ordinary level for a mid-continental area. The Narin basin was more normal in this respect, for while its area was slowly warped into basin form, centripetal streams carried abundant waste from the ele\-ated margins toward the depressed center, and the latter was aggraded at the expense of the former. The lenses or channel fillings in the mar- ginal conglomerates on the upper Maknial were from 30 to 70 feet wide and up to 10 feet thick. They usually showed cross-bedding, and were commonly of different texture from that of the bed in which the channel had been eroded. The lenses in the gray clays, well exposed on the south side of the Alabuga for several miles below the new road bridge, are ver}- numerous. They are from 20 to 100 feet wide and from i foot to 10 feet deep. They frequently exhibited a gentle cross-bed- ding. All the lenses were convex downward and plane upward. There can be little doubt that they represent cross-sections of the shifting channels of the streams by which the basin was aggraded. THE PERIOD OF DEFORM.^TION AND EROSION. The Narin strata have been much deformed on certain lines, but as a whole they have not been greatly disturbed. A generalized cross-section of the basin is given in fig. 57, representing a breadth of 20 or 30 miles. The dip of the basal g^^^^^^^^^ ■\\\\\\\\\\\\\v^^^ Fig. 58. — A small Monocline in the Narin Formation, looking east. Fig. 59. — Three-mile section through Ulu-tuz Gorge, looking east. conglomerate along the border of the Chaar Tash is sometimes as much as 50° or 60°, but this measure decreases rapidly as one enters the basin. A well-defined monoclinal flexure, trending about east and west, was crossed as we followed down the Makmal. A small monocline of diagrammatic pattern, with a displacement of about 300 feet, was seen a few miles farther south ; it is sketched in fig. 58. The strong and complex anticline, by which the lower beds are brought to light near 94 EXPLORATIONS IN TURKESTAN. the axis of the basin, nins about parallel to the Alabuga on its north side for some 50 miles west of its junction with the Narin. The trail crossed this anticline in the Uhi-tuz gorge, a few miles west of the new bridge over the Alabuga, and there we saw a section about 3 miles long, gi\en in fig. 59. Beds of salt and g}-psum occur in the center, and are greatly deformed. Bad-land clays lie horizontal on the north, and sandstones and clay-beds dip steep to the south on the south. The little stream in the gorge was intensely salt. Some miles farther east, beyond the transverse gorge through which the Makmal comes to the Alabuga, the anti- Fig. 60. — The Alabuga Valley, looking north. The east end of the Chaar Tash Range is seen over the dissected anticlinal ridge ot the Narin formation; gypseous efflorescence whitens the transverse gorge walls in the anticlinal ridge. Kirghiz Tombs in the foreground. cline has overturned dips on the south side and rises in a strong ridge, on which the g>'pseous efflorescence, seen in the distance, was at first mistaken for snow (fig. 60). Where we left the Narin basin on our wa)- to Son Kul, the border of the formation seemed to be determined by a fault, as suggested in fig. 61. A large part of the Narin fonnation, where we saw it, has been reduced to a peneplain along the larger streams since its deformation, and this peneplain is now trenched b\' terraced valle)-s, further considered below, with much bad-land dissec- tion of the clay beds in the residual uplands and on the valley sides. It was here that we saw that the bad-land forms were developed in sharpest detail on the southwestern slopes, while the closely adjacent slopes to the northeast had a thin cover of herbage and a smoother form, as noted in an earlier paragraph. RIVERS AND VALLEYS OF THE TIAN SHAN. 95 We were led to conclude that the crustal movements during the deposition and the deformation of the Narin strata should be associated with the movements that have given rise to the present relief of the Tian Shan. The red color of the basal beds, seen not only on the south side of the Chaar Tash, but in the southern distance along the north base of the Kalkagar-tau, is consistent with the reduction Fig. 61 . — Four-mile section across the northern border of the Narin formation, looking east. of the region to lowland form before the beginning of the deformation by which the Narin deposits were initiated ; yet the inclosing ranges to-day have serrate crests without indication of having ever been peneplained. Some smaller valley deposits, probably of Tertiary- date, will be described in the next section. THE RIVERS AND VALLEYS OF THE TIAN SHAN. If the theoretical considerations presented in the chapter on the Tian Shan are well based, we should expect to find streams of several kinds among the western ranges of this mountain system. Those of the first kind would continue from the fonner cycle of erosion, but would be revived to renewed activity in consequence of a favoring elevation of the region. The \alleys of these revived streams would be seen to-day where the relief of the fonner C3-cle remained in greatest strength, or where the new uplifts did not defeat the streams. Streams of a second kind would persist from the antecedent cycle of erosion in spite of an unfavorable elevation of the region. The valleys of these antecedent streams would be expected where the streams were largest and where the unfa\'orable uplifts were not too strong. Streams of a third kind would be of new establishment, following the slopes produced by the movements which introduced the new cycle. They might be called new consequents, and they would be expected where the movements were strong and the pre-existent streanas were weak. A fourth class of streams would include all those developed in the new cycle by headward erosion along belts of weak structures exposed in the \-alleys of the other class. Such would be called new subsequents. Examples of revived streams are probably to be found in the central plateau- like region described in Mr. Huntington's report. The gorges cut through some of the ranges suggest an antecedent origin. The gorge by which the Narin cuts through the eastern end of the Chaar Tash, just below the entrance of the Alabuga, the gorge of the Juvan-arik in the Yukok-tau range (fig. 43), and the Buam gorge of the Chu northwest of Issik Kul, all may be of this kind ; but the case is not clear. New consequents appear to be numerous on the northern face and on the southern back slope of the Alexander range, and in the longitudinal depressions between the ranges near the west end of Issik Kul. New subsequents of relatively small size are probably of common occurrence as branches of all the other kind of streams. g6 EXPLORATIOXS IN TURKESTAN. RIVERS OF THE ISSIK KUL DISTRICT. The rivers in the Issik Kul district proclaim their association with new-made ranges by their habit of (until recenth) aggrading the longitudinal valleys and of eroding the transverse valleys. This is notably the case in the members of the Chu system. The lower Tuluk Valley contains in its longitudinal portion several hundred feet of yellowish clays, interstratified with lenses and layers of coarse gTa\els and cobbles, all now dissected. The stream turns abruptly north- ward from this aggraded and dissected trough to a deep and narrow gorge through the eastern extension of the Chalai range, and then joins the Juvan-arik. The gorge is passable at low water, but at the time of our \isit the Tuluk-su was too high to pennit us to follow it, and we had to make a detour over a low pass. The upper (western) part of the Tuluk \'alley, where we first came to it north of Son Kul, did not present any sure signs of being a valle}- of recent deformation ; its sides were well dissected ; its lower spurs were well graded ; its present flood plain was eroded 50 feet or more below an earlier valley floor ; yet all this is consistent with the origin of the valley by subrecent defonnation, followed by dissection of its sides, accumulation in its most depressed part, and erosion of its transverse ^ALEXANDER RANGE Kachkar Basin KOK-TAL RANGE Fig. 62. — Fifteen-mile section across the Kach-kar Basin, looking east. outlet. The change toward a more arid low-level climate, indicated by an increas- ing sparseness of vegetation as we rode down the \alle)-, was distinctly noticeable in a distance of 10 or 15 miles. The Ju\an-arik comes from the east in a longitudinal valle)' on the south side of the Terskei Ala-tau ; then turns northward near the junction with the Tuluk-su and follows a deep gorge (fig. 43) — one of the wildest gorges in the Tian Shan, accord- ing to Severtzof (1875, 73) — through the range, here called the Yukok-tau (Son Kul Gebirge on Friedrichsen's map), to the Kach-kar basin. The longitudinal valley contains clay deposits of a yellowish or reddish color, but these are now so deeply dissected as to expose the rock floor on which they rest. Since the deep dissection there has been an accumulation of gravels and cobbles, capped with gra)- silts, but these deposits are also trenched, and the present river flows in an open flood plain below the terrace remnants of the gravels. The traus\-erse gorge has steep, ragged walls of granite, basalt, and diorite, between which the ri\-er rushes on a rapidly descending bowlder bed. There are few signs of terracing in the gorge, but where lateral ravines open in the walls, benches of gravel remain. The Juvan-arik joins the Kach-kar in a longitudinal basin of the same name, and their united waters flow eastward and northward toward Issik Kul, under the name of Urta-takoe. The Kach-kar basin has already been referred to as an aggraded area of depression correlated with the uplifted and dissected block of the BASINS AND GORGES OF THE CIIU. 97 Alexander range on the north. Near the soutliern border of the basin are some ridges fonned of clay beds, probably Tertiary', tilted to the south and eroded, as in fig. 62, and thus suggesting progressive deformation of the bordering mountain blocks, as in the Narin basin. The passage of the Juvan-arik through the clay ridges is marked by terraces at three levels. Farther on there is a broad plain near the grade of the present rivers. The topography of the district must hav^e been ver^- different when the clays were deposited, for the rapid river is now and has long been washing coarse waste in abundance from its gorge in the Yukok-tau, The clays may, therefore, be provisionally referred to an early period of defonnation, before the surrounding region had gained a strong relief. Their defonnation and progressi\-e degradation may be associated with the stronger dislocation and dissec- tion of the inclosing ranges. The Urta-takoe soon leaves the Kach-kar basin by a rather narrow valley, and enters a second basin in the center of which lies Urta-takoe post-station, just south of a superb fan that is washed from the block range on the north. The longitudinal valley here has even,- appearance of being aggraded, especially to the east, where the waste that is washed in from the higher range on the south has built up a long, slightly convex filling against the middle of the smaller range on the north. Mention of this has already been made in connection with the block moimtains of this district. The ri\er runs northward through a gorge and thus reaches the western end of the Issik Kul basin, where a great volume of gravels has been deposited and afterward more or less dissected. Some of these gTa\-els will be mentioned in the section on the lake basin. The river that we have been following is called the Chn after passing the west end of Issik Kul. For the next 20 miles it follows a rather open \-alley westward, with an extraordinar)' exhibition of terraced alluvial deposits, including cream- colored clays and hea\y gravels. Then the deep and wild Buani gorge is followed northward. The river here flows at great speed in most tumultuous fashion for miles together. Its descent is so rapid that the road alongside of it was often undesirably steep. The iutrenchment of the gorge is evidently still in active progress ; yet even here, where the walls are steep and ragged in resistant rocks, and where there is often not even the beginning of a flood plain, some small tributary streams enter the Chu practically at grade. At Kok-muinak station the gorge opens upon a wide basin, where the river has made some fine terraces by cutting down through its fonner gravels and into the rock beneath. The persistent alternation of open longitudinal valle\s with silts and gravels and of narrow transverse gorges with bare rock walls, taken with the ungraded character of the river in the gorges, gives strong evidence of subrecent displace- ment of the ranges in the Chu basin, and thus confirms the inferences based on the form of the mountain blocks. THE KOGART TERRACES. Terraces occur in all the valleys that we followed. The best examples will be briefly described, beginning with those of the (western) Kugart, where we first entered the mountains. This valley seems to have been eroded to a much greater 98 EXPLORATIONS IN TURKESTAN. depth tlian it now possesses and "then heavily aggraded, mostly with gravel, but with some silt layers, so that its floor gained a breadth of 3 miles in its lower course. It was during this aggradation that we suppose the loess of the hillsides to have been supplied from the flood plain of the wandering river. Since then the river has returned to its fonncr habit of erosion and valley deepening, as a result of which several terraces have been developed. Those near the mouth of the Karalma (fig. 63), a branch from the north, are drawn in section in figure 64. Here the river is nearlj' 300 feet below the upper plain. Fans of half-mile radius are built on the plain by streams issuing from the range on the south. The \-alle\- is here bordered on the north side by bluffs of bedded conglomerate and silts, which rise several hundred feet above the upper plain, and show a moderate northwesterly dip, thus suggesting that there have been alternations of degradation and aggrada- Kig. 03. 1 enaces of the (western) Kugart, looking northeast. tion, associated with slight uplifts, in this district. The stream ran near the north side of its valley for the lower 30 or 40 miles, and the road that is projected to cross Kugart pass followed up the broad terrace plain on the south side ; but just above the village of Taran Bazaar the stream lies along the south side of the valley, where it is locally superposed on a belt of limestone to the south of its fonner course, and a narrow gorge results, as in figs. 65 and 66. We here met one of the engineers in charge of the road construction, who said it was intended to cut a roadway on the southern wall of the gorge, and thus avoid the necessity of bridging the river. In the meantime the Kirghiz ford the river just below the gorge and then follow up the terrace on the north side of the upper valley. We took guides for the ford, and were more fortunate than some wayfarers who had preceded us by a few hours, as one of their pack horses had been drowned in the crossing. TERRACES IN THE KUGART VALLEYS. 99 The terrace plain continues far up the Kugart-su, l)ut it becomes narrowed and the river often cuts through the gravels to the rocks beneath. The rocks are weak red beds for several miles, in which the hills are low and the valley sides are scarred with landslips. Farther on schists and slates set in, the mountains Fig. 64. — Three-mile section across the (western) Kugart Valley, looking northeast. rise, and the valley narrows. The upper terrace plain is then more built upon bi- lateral fans and more trenched by lateral streams, so that the trail along it has an uneven grade. At the mouth of the Kizil-su a fine exposure of the terrace con- glomerates is seen, several hundred feet in thickness. Above the Kizil-su cobbles and roughly-rounded blocks are found in patches on the mountain side above the terrace plain, as if they marked the remnants of some still earlier \-alley filling whose terrace form is now lost. Farther on in the mountains the stream rises Fig. 65. — Goige of the (western) Kugart, above Taran Bazaar, looking east. above the terrace level, and the valley floor is encroached upon by torrent fans from lateral ravines. Here we camped in the rain, about 5 miles below the pass, on June 30. The discomfort of bad weather was removed by the thoughtfulness of our good friend, the Min-bashi, who had given orders to send a party of Kirghiz ahead with yurts. When we reached the camp the yurLs were already set up and well furnished for a comfortable night. ICX3 EXPLORATIONS IN TURKESTAN. After we had crossed the Kugart pass, in the Fergaua range, and descended into the valley of the (eastern) Kugart-sn, another finely developed system of terraces was fomid. The main and branch valleys here, below the torrential head- waters, were eroded in a broad basin of tilted conglomerates that probabl}- belong with the Narin fonnation. The spurs of the conglomerate hills rose above the highest terrace (fig. 67). Here and else- Fig. 66.— One-mile section of Gorge in the (western) Kugart where the bills and spurS Were dissectcd Valley, looking northeast. , , , , . , ,, by rather close-spaced ravines, and tlie slopes were beautifully graded. The terrace plain ascended with a rather strong gradient into the embayments between the spurs. In such a case it is evident that the material of the terrace was deri\-ed from the side vallevs as well as from the Fig. 67. — Upper Terrace of the (eastern) Kugart, near the Kirghiz Bridge, looking southwest. Dissected hills and spurs of tilted older conglomerates in the background. main valley. The stream has intrenched itself 225 feet below the upper terrace plain at the Kirghiz bridge, carving se\-eral terrace benches in the process. The upper terrace plain and the stronger terrace benches continue for 10 or 12 miles northward toward the Narin Valley. A mile upstream, south, from the rude Kirghiz bridge by which we crossed the ri\-er, a westward swing of its course TERRACES IN THE KUGART VALLEYS. IO.I undercuts the whole thickness of the valley-filling, up to the upper plain, and shows the half-cemented conglomerate in a fine bluff (fig. 68). Many little terraces occur on the opposite side of the stream. Several large landslides have invaded this valley from the granitic Chaar Tash range on the southeast. The first one noticed was just below the Kirghiz bridge across the Kugart-su. No verv' distinct scar was to be seen on the mountain side, but the path of the slide was marked by a wide belt of confused bowlder-strewn knobs and mounds that stretched for 8 or lo miles northwestward from the mountains down a moderate slope to the terrace plain. Curiously enough, the extremity of the slide lay, 150 feet thick, on the plain on the farther (northwest) Fig. 68. — Gravel Bluff in ihe Terraces of the (eastern) Kugart. looking south. Spurs of conglomerate in middle distance; the Fergana Range in the background. side of the river trench, and rose 100 feet higher there than in the tunuilt of mounds on the nearer (southeast) side, as in fig. 69. The slide had evidenth' taken place before the river had deeply intrenched itself beneath the plain, for the walls of the trench gave a good section of the irregular landslide mass resting on the well-stratified conglomerates ; and in such a case one might expect the river to have been turned from its former course to a new channel around the end of the slide; but as this did not happen, we may suppose that the river maintained its course by enlarging the leaks and passages through the slide. We had a fine view of the valley from the high terminal mounds of irregiilar form, composed of angular I02 EXPLORATIONS IN TURKESTAN. granitic fragments, with many large blocks, lo or 15 feet through. Some other large slides were crossed fartlier south. These came from the west end of the Chaar Ta.sh and ran \vestward into the valley of the Oi-kain, a branch of the (eastern) Kugart-su. One of the slides blocked the valley and caused the formation CHAAR-TASM RANOC Fig. 69. — Ten-mile section of a Landslide in the (eastern) Kugart Valley, looking north- east. The present river valley is eroded in horizontal gravels that occupy an older and much wider valley eroded in tilted conglomerates. of a large meadow, now .somewhat terraced, ne.xt upstream. A little farther south the Oi-kain has been superposed on the resistant rocks (apparenth- limestones) at the southwest end of the range, and has there cut an impassable gorge ; hence the trail climbs over the ridge on the southwest and then descends into the open upper valley of the same stream. THE TERRACES OF THE NARIN BASIN. The terraces of the Alabuga River in its valley through the Narin formation were among the most interesting that we saw. It has already been stated that the Narin conglomerates and clajs had been much eroded after their deformation. The terraces now to be described occur in the valley that has been eroded below the broadly degraded surface — a true plain or a peneplain over large areas — of the Narin strata. The terraces were first seen in the valley of the Makmal, where three or four steps occurred. The uppennost Makmal plain was broadly sheeted over with gravels, even where it tnnicated the tilted clays. The spurs of the higher terraces, Fig. 70. — Tv^o-mile section of Terraces in Alabuga Valley, looking east. as well as the residual hills that surmoinit the highest plain, assume a more and more minute pattern of dissection or bad-land fonn, as the clayey strata toward the center of the basin are reached. After passing southward through the Ulu-tuz gorge in the salt-bearing anticline, we came out upon a well-defined terrace plain of the Alabuga \'alley and crossed it to the trench of this river, which was incised 150 or 200 feet below the plain, as in fig. 70. Here several terraces were seen on the north side of the trench, while a single bluff rose on the .south side. The bluff showed a heavy deposit of gravel, capped with 20 or 30 feet of fine gray loess-like silt at the level of the terrace plain. Many springs issue from the blufll" at the ORIGIN OF THE TERRACES. 103 surface of contact of the gravels on the Narin clays. Tlic river is now so rapid that it washes along heav>' cobbles. A much gentler current is suggested by the silts that cap the gravel bluff. As the Alabuga is followed eastward, a graded plain makes its appearance 300 or 400 feet above the terraces just mentioned. It is this higher plain which consti- tutes the peneplain, woni on the disturbed Narin fonnation. Bad-land residuals, 100 or 200 feet in height, still sunnount it here and there ; yet in the district where the road crossed over its remnant spurs, the peneplain must have occupied nine- tentlis of the basin floor south of the river before the present valleys were cut below it. The peneplain here is cloaked with from 30 to 50 feet of gravel, which lies unconfonnably on the beveled surface of the tilted clays. At some points a heavier brown conglomerate is locally developed at the base of the gravels, as if it were the channel fillings of a river. Its outcrops are rather strong, and large blocks from it creep down the clay slopes beneath. Near the junction of the Alabuga and the Narin, the lower terraces seemed to involve successive alternations from erosion to deposition, as indicated in fig. 71. A wide, open valley, car\-ed in the tilted Narin clays, was filled to a depth of more than 150 feet with silts. A smaller valley was eroded in the silts, then partly filled with a deposit of gravels. The present ri\-er plain is eroded about 30 feet below the gravel plain. The Narin, flowing northwestward, soon enters a narrow gorge that is cut through a sag in the mountains between the Chaar Tash and the Dongus-tau ranges. The red basal beds of the Narin formation were seen in the gorge. Our road followed up the south side of the Narin, where terraces continued similar to those already described. When we camped on its banks for the night, clear, cool water was found at the stream's edge, issuing from the gra\-els of the terrace to mingle with the turbid current of the river. The river was said by the Kirghiz to have a daily fluctuation of level, and to be lowest at about 10 o'clock in the morning ; hence that time was chosen for fording it the next day, July 7. It was then about a foot lower than when we came to it the evening before. The terraces of the Juvan-arik have already been mentioned. The Ula-khol, a small river entering the southwestern part of Issik Kul, has several terraces eroded in tilted conglomerates a few miles from the lake. Fig. 71 -Three-mile section of Terraces at the junction of the Alabuga and Narin f^ers, looking east. ORIGIN OF THE TERR.\CES. Many more examples of terraces are described in Mr. Huntington's report, where strong reasons are given for ascribing the terracing of the valleys in the Tian Shan to climatic changes. It may be here pointed out that none of the terraces described in the preceding paragraphs resemble the terraces of New England in depending on ledges of resistant rock for their protection. If a Narin terrace 104 EXPLORATIONS IN TURKESTAN. (B, fig. 72) has not been destroyed by the widening of the valley (Y), this is not because the widening of the valley has been prevented by the lateral encounter of unusually resistant rocks, but because the river spontaneously ceased its destnictive work when the lower valley was significantly narrower than the upper \'alley (V), instead of continuing to widen the lower \-alley so as to combine the two terraces, A and B, in a single terrace, A'. All the terraces of the two Kugarts and of the Alabuga-Narin Valley, and at least some of those of the Chu system, thus appear to result from successive reductions in the power or in the period of river action. The same holds true in the case of the terraces in the Kopet Dagh, above described. Here, as well as there, it is not likely that the terraces now seen record all of the terrace-making episodes, but onl)- the decreasing maxima iu a complicated series. It should also be pointed out that the terraces of New England and of the Tian Shan appear to be of unlike age. Those of New England are eroded in loose sands or clays, and are all of later date than the last glacial epoch. Indeed, their production may have required less than half of post-glacial time, for the valleys iu which they were car\^ed were aggraded, after the ice retreated, by the same rivers that are now degrading them ; and the existence of the ter- races shows that less material has been removed than was previously deposited. The terraces of the Tian Shan, on the other hand, are usually eroded either in rather well knit gravels or con- glomerates, as along the two Kugarts, or in partly consolidated sandstones and claystones, as in the Narin fonnation, while in the Kopet Dagh they are car\-ed in calcareous shales. In all these cases the terrace materials are strong enough to stand up in steep bluffs. None of these terraces are in glaciated valleys. The earlier terracing appears to be much more ancient than the latest moraines in the high mountain valleys. It is therefore quite conceivable that, as Mr. Huntington has concluded, the successive glacial epochs and the successive terracing epochs, each of decreasing intensit}', may be synchronous, and may be common results of a series of climatic changes. Whether it is finally proved that the terraces result from climatic changes, or whether the terraces are in part the result of cnistal movements, there appears to be good ground for thinking that the time internals marked by the terraces may be correlated over ver}- considerable distances, and that the time inter\-als thus established ma}- be eventually placed in the same scale with those indicated b}- the glacial records ; and that thus a good beginning toward the establishment of a Quaternar}' time scale will have been made. Fig. 72. — Ideal section of Terraces. THE ISSIK KUL BASIN. 10 = THE ISSIK KUL BASIN. Issik Kill, or the ''Warm Lake," is 115 miles long and from 20 to 35 miles wide. Its surface stands 5,300 feet above sea-level. The bare mountains around it are picturesque, but the barren, stony piedmont slopes, several miles in breadth, greatly lessen the beauty of the scener\-. The basin of the lake resembles that of the Narin Tertiar\- formation, in that both have been produced by the deformation of a previously degraded mountain region and that both have received much waste from their uplifted borders ; but they differ in that the defonnation of the Xarin basin ceased so long ago that its deposits are now well dissected by the trunk and branches of an outflowing river, while the deformation of the Issik Kul basin has been continued into so recent a time that it holds a large lake, from which there is at present no outlet. The lake surface and the surface of the present Narin Valley are of similar altitude, something over 5,000 feet above sea-level. It is ver}- probable that the original floor in each of these basins now stands below sea-level, but as it is concealed beneath a co\-er of deposits or of water, the depression excites less attention than it would if it were open to observation ; yet as far as the mechanics of the earth's crust is concerned, one case is, as has already been pointed out, as remarkable as the other. Evidence of the previous degradation of the region in which the Narin basin was bent down is found in the relatively even trend of the red basal con- glomerates which rose even along the southern side of the Chaar Tash range; for if the surface on which the conglomerates were deposited had been of strong relief, their outcrops and the slopes of the Chaar Tash rocks could not have come together on so e\en a line. The evidence of previous degradation in the region of the Issik Kul basin is foiuid in the even sky-lines or back slopes of several of the neighboring mountain ranges, as already described. The ranges are now much dissected, and deposits of their waste are found not only in the stony piedmont slopes with which the lake is surrounded, but also in older clays and conglomerates, now more or less deformed and eroded, aroimd the borders of the lake. THE EARLY BASIN DEPOSITS. Hills and ridges of eroded conglomerates were seen south of the lake when we ascended the Ula-khol ; their total thickness may have been several thousand feet. These uplifted conglomerates fall off" northward toward the lake in a rather well defined subrectilinear bluff east of the Ula-khol. A lower bluff, subparallel to the first, stands a little farther forward ; then comes the fan of the Ula-khol, in which the stream has now eroded a shallow trench. Not far forward from the second bluff", a third bluff or scarp, from 5 to 15 feet high, crosses the delta, and this one seems to be the result of recent displacement. This scarp can not be considered a high-level shore-mark of the lake, for instead of contouring around the Ula-khol fan in a level line, it passes over the gentle arch of the fan in a relatively straight line. It will be remembered that a similar displacement was noted in the waste fans piedmont to the range at the west end of Issik Kul. I06 EXPLORATIONS IN TURKESTAN. A point between two bays at the west end of Issik Kul is caused by ridges of dissected conglomerates, bordered north and south by low gra\'el plains of gentle grade, sloping from the Chu toward the lake, and probably representing former deltas of the Chu when it flowed into Issik Kul. That it had probably once done so was recognized by Severtzof in 1867 (1875, 82). The Chu has now a silt cover on its flood plain near the lake, but shows gravels in its .shoals. If the silts were laid over the plain of its fonner delta, they have been removed. The Kirghiz have led some small canals from the Chu eastward across the southern delta plain toward the lake. The water thus gained is distributed on fields of fine soil not far from the lake shore. A pair of whitish clay belts, about 5 feet apart, vertically, was seen contouring around the slopes that inclose this plain. We took them for shorelines at first, supposing that the clay had accumulated in the presence of reeds or grass, by which wave action was held off, as is now the case on parts of the Son Kul shoreline ; but cla}- belts were not seen eastward along the northern shore. These belts are probably 50 feet higher than the well-detennined shorelines traced at and below the 25-foot level; moreover, similar clays in greater volume were seen at the north base of the conglomerate ridges between the two gravel delta plains, and in much greater volume farther down the Chu Valley ; so the origin of the clay belts is left in doubt. On the north side of Issik Kul the piedmont waste slope is rather e\enh- develoj^ed for the first 50 miles eastward from the west end of the lake, although some local varicolored ridges rose through the waste slope at a few points where its breadth was greater than usual. For the ne.xt 20 miles, nearly to Sezanovka, the slope was often made ver)- une\en by a succession of irregular ridges of disturbed and dissected basin deposits of variable texture. The finer sandy or silty layers here seen were frequenth' co\-ered with hea\')' bowlders up to 8 or 10 feet in diameter. Some of the ridges thus formed are naturally eroded ; others have comparatively simple fonns, with even scarps 200 or 300 feet high, facing the lake, in which only narrow trenches ha\-e been cut It was e\-ident that these ridges resulted from the recent disturbance of the earlier basin deposits. THE PIEDMONT SLOPES AND VALLEYS. Since the disturbance of the earlier basin deposits there has been time enough for the intennittent streams to fonn the newer piedmont fans and slopes of waste, which now stretch forwai^d for from 3 to 10 miles with moderate declivit}- from the mountain base to the lake. Trains of hea\'y bowlders were seen on some of the fans, as if marking the paths of exceptionally hea\'}- floods. Parts of these newer slopes are of coarse surface materials, and the subangular stones there are darkened with "desert varnish." Other parts are more gravelly and of lighter color, as if of somewhat more recent date. On both parts the scant}' herbage is not alwa)'s uniformly distributed, but sometimes occupies interlacing lanes, inclosing barren spaces a few feet in diameter. The delta of the Ula-khol and the abandoned delta plains of the Chu are also seemingly of modern date. At the east end of the lake Mr. Huntington reports the occurrence of an extensive plain 40 miles broad east and west and about the same north and south, CHANGES IN THE LEVEL OF ISSIK KUL. 10/ of cross-bedded sands and gravels, with occasional silty layers, sloping toward the lake. Here and there low hills rise over the plain. The hills are chiefly made of silt, but contain also certain laj-ers of rough gravel with broken shells of land snails. The bod}- of the plain is about 200 feet above the lake. During the formation of the plain, the local baselevel at the eastern end of the lake may have been relatively higher than now, but whether the strata of the plain are fluviatile or lacustrine does not clearly appear. Semenof noted the marginal conglomerates in 1856, and inferred from them that "the lake in former times occupied a far more extensive basin" (1869, 331). The same explorer states that the mountains on the north of the lake are named from the Kirghiz word "kungei,'' meaning "toward noon," and those on the south from "terskei," meaning "toward midnight," thus referring to the opposite aspects of the two piedmont slopes (1858, 359). Severtzof noted in his journey of 1867 that the Ak-su, entering Issik Kul at the southeastern corner, had cut its \-alley through 200 feet of sands and conglomerates, and inferred from this that the lake was once higher than now (1875, 21 J. Capus (1892, 56) and Schwarz (1900, 581) probably base their statements that Issik Kul once stood 60 meters higher than now on Severtzofs obser\'ations. All estimates of the fonner higher stand of Issik Kul based on the distribution of sands and con- glomerates seem untrustworth}', because such deposits are more likely of fluviatile than of lacustrine origin. The piedmont slopes and the eastern plain are not now in their original condition. They are more or less dissected by open \alle}s and branching gullies. The valleys are not distinct near the western end of the lake. They are from 50 to 70 feet deep where we crossed many of them on the northern piedmont slope a few miles back from the midlake shore, but tlie\- decrease to less and less depth toward the present shoreline. The eastern plain is well dissected b}- branching terraced valleys with open straths. Even at the shoreline the valleys at the middle, and still more at the eastern end of the lake, are eroded distinctly beneath the piedmont and the eastern plains ; and, as will be more fully stated below, the lake waters now invade the valley mouths, the invasion being of increasing measure eastward. It is inferred from this that the sloping plains were not graded with reference to the present level of the lake, but with reference to a lake surface that descended gently eastward with respect to the present lake surface. The valleys emphasize this conclusion. It has just been mentioned that they increase in depth as one passes from west to east, along the north side of the lake. The>- were not noticed at the west end. They became serious obstacles in road building near the middle of the lake, and at its eastern end the road winds about on tlie plain to avoid them ; hence it is probable that the cause of the valle\' erosion should be associated with a tilting of the lake basin, whereb\- the eastern end was raised more than the western, after the piedmont slopes and the eastern plain had been fonned. Climatic change is also to be considered as a cause of the valley erosion, because the depth of the valleys below the piedmont slopes increases toward the mountains. This indicates a change in the regime of the streams, such as a change of climate commonly produces, and such as is commoidy associated with io8 EXPLORATIONS IN TURKESTAN. a change from a glacial to a tionglacial epoch. It would be an aid in the elucida- tion of these changes if soundings could be made to determine how far the pied- mont slopes continue their present declivity under the lake, and how far forward the valle\s may be traced. This would be of especial importance in connection with the ruins that are found submerged in the lake, as mentioned below. The onl)' suggestion that we can make as to the date when the piedmont waste slopes were formed is based on the occurrence of the moraine, already described as standing a little forward from the mouth of a valley in the Kiuigei Ala-tau, north of Choktal post station, about 1,500 feet over the lake. If one may judge by the relation of moraines and aggraded waste slopes elsewhere in the world, it is probable Fig. 73.- -A Drowned Valley in the Plain al the east end ol Issik Kul, looking northeast. that the formation of this moraine and the aggradation of the piedmont slopes were contemporaneous ; hence the erosion of the valleys is of later date than the glacial epoch in which the moraine was found. Inasmuch as the moraine here referred to was the lowest one that may have been fonned in its valley, it apparently belongs to the earliest of the glacial epochs established in Mr. Huntington's report. It appears from the foregoing that the Issik Kul basin has long been suffering disturbance and receiving waste from the surrounding mountains, and that the latest disturbances of level have been greater at its eastern than at its western end. We have next to consider the more modern history of the lake itself. RECENT CHANGES OF ISSIK KUL. 109 THE RECENT CHANGES OF ISSIK KUL. The lake was lower and siiialler than it is now at a time not long past, as is shown by its recent invasion of the valleys that have been worn in the piedmont slopes. The low-water stand is believed to have been of later date than that of the Choktal moraine al)ove mentioned. The invasion of the valleys was not noticed at the western end of the lake. It was first seen in moderate development in the western quarter of the northern side, and became distinct a little farther east. It is described by Mr. Huntington as a notable feature of the east end of the lake, where the valleys, eroded in the sandy plain, are now drowned so far as to produce long, narrow bays. The scenery of the plain is dull and uninteresting, except for the \iews of the surrounding mountains ; but when one comes unexpectedly upon the drowned valleys, with their long, cur\-ing lanes of blue water and their green shores, the view becomes attracti\'e at once (fig. 73). Hence, like the erosion of the valleys, their drowning becomes more pronounced as we go from west to east. The contrast between the shorelines at the northwest end, the middle, and the northea.st end of the lake is strikingh- shown in the diagrams of fig. 74, which are reduced from the 2-verst map. The rise of the lake carried it to a higher level than that of to-day, but it remained there only long enough to cut or build a series of moderately developed shorelines, which were first recognized by Semenof in 1856, who .said that the lake seemed to have receded firom them, as if contracted in its bed (1858, 359). At the .southwest corner of the lake, where the bordering plain was low and marshy, we found a well-defined reef of small rounded pebbles, 3 or 4 feet high, 25 feet above the present shoreline, and a smaller sand reef at 10 feet. The present shore was marked b}- a low sandy beach or reef, often shutting in a narrow lagoon. At the northwestern comer of the lake, low reefs of sand or fine gravel were noted at heights of 2, 3, 5, 10, and 25 feet. At Tur-aigir station, about 15 miles from the west end of the lake, a 4-foot bluff stands about a quarter mile back from the shore, with its base 25 feet over the lake; and a beach was found 5 feet o\-er the lake. It was near Choktal station that we first noted that the raised beaches are of later date than the valleys. One example from man)- is illustrated in fig. 75. The surface of the piedmont slope is so smooth that the general shoreline is here notably even ; but a small point is made by a trail of coarse bowlders, some of which are 8 or 10 feet in diameter at a distance of 3 or 4 miles from the mountains. The valley here was 6 or 8 feet deep and 70 or 80 feet wide. The stony 25-foot beach or reef was prolonged directly across it, except for a little notch by which a small stream escaped. Se\eral lower shorelines were seen in the \-alley floor. In another Fig. 74. — Shorelines ot Issik Kul at the north- west end (A), the middle (B), and the northeast end (C) of the lake, reduced to 18 versts to an inch from the 2-verst Russian map. no EXPLORATIONS IN TURKESTAN. "III'"-.iIII///...um;, 25 foot beach "•"""". "li"'"'IMlll|,,„, = ■'■ ?.oV = ""■.„o;!,. """"'■""" 3 o,''o.6*"'""nii''»i((v example, a reef 15 or 20 feet high was built across a valley that was 30 or 40 feet deep. In a third example, beds of silt had been laid on a valley floor behind a reef, but at present the reef and silts are both trenched b\- the stream, which is washing cobbles through them. In this district some trenches of the 25-foot reef were 30 feet wide and 6 feet high on the outer face, with cobbles up to 6 or 8 inches in diameter; and one of the cut bluffs was 8 or 10 feet high. East of Sazanovka Mr. Huntington reports a beach nearly 100 feet wide and a cut bluff 35 feet high. Here and farther east the elevated shoreline is usually indicated on the 2-verst Russian map. The increase in the strength of these features from west to east is probably to be accounted for by the prevalence of waves caused by westerly winds, whose action would be least effective at the west end of the lake. The only point where we saw a rocky shoreline was between Chelpan-ata and Kurum-dinskya stations, about 50 miles from the west end of the lake, where a low granite bluff rose at the lake border. It stood in a small em bay men t, because the piedmont slopes had grown somewliat farther forward on each side of it. Strati- fied deposits of rather fine texture, covered with bowlders, rested on the lateral slopes of the granite. These seemed to be of earlier date than the modern piedmont slopes. Two ele\-ated beaches ha\'e been fonned by undercutting the steep slopes of angular waste on the granite bluff, as in fig. 76. The upper beach is the stronger of the two, and is recognized not only b)- its fonn, but by the abrupt change from angular blocks above its line to rounded cobbles below. Here only was an)- direct suggestion found as to the relative date of the two beaches. It seemed that, if the lower one had been made first, it would have been more obscured than it is by waste from the upper one ; hence the lake probabl)' rose rapidl)- to the 25-foot beach and paused during its fall at the lo-foot beach. At the eastern end of the lake, the highest beach is described b)- Mr. Hunting- ton as contouring around all the land arms that separate the drowned valleys of the plain. Its height there is given as 30 feet. The 2-verst map shows the shore- line then to have been even more irregular than it is now. The beach is easily distinguished from the valley terraces, for it runs at a level and ends somewhat inland from the bay heads, where the valle)- floors rise to its level ; while the terraces have sloping floors and extend farther up the vallej-s. When Issik Kul was first described to us as a lake without an outlet and with abandoned shorelines, we had hopes of finding a record that might compare with that of the Bonneville basin, but there seems to be little likeness between the two. Issik Kul only just fails of having an outlet to-day, and, as will be shown below, its level has probably been regelated by overflow to the ri\'er Chu through much of its subrecent J'SsiK KIJL Fig. 75. — Diagram of the relation ot a Valley, the raised Beaches, and the present Shoreline of Issik Kul. RELATIONS OF THE RIVER CIIU TO ISSIK KUL. Ill histon-. Its abandoned shorelines seemed to be more recent than the glacial epoch, and the variations that t!ie\- represent are perhaps as well explained by the varying relations between the river and the lake as by climatic changes ; but it is evident that the two processes may ha\-e worked together. RELATIONS OF THE RIVER CHU TO ISSIK KUL. Issik Kill at present has no outlet, and the lake water is very slightly brackish. The Kute-maldy, a short outgoing branch at the elbow of the Chu (K, fig. 43), flows into the lake at its western end. When seen on the map, this stream would naturally be taken for the lake outlet ; so indeed Humboldt and Ritter are said to have thought. Various legends are current around the lake as to the origin of the Kute-maldy. A postmaster gave us a ver\- circumstantial stor\' of how a Kirghiz khan, some fifty years ago, tried to drown out his enemies down the valley of the Chu by cutting a canal from the lake to the river, hoping in this way to create a devastating flood ; but the lake proved to be lower than the river, instead of higher, as had been expected, and so the water ran the wrong way. Another postmaster told us most explicitly that a canal was cut by the Kirghiz, about thirty years ago, so as to drown out Tokmak and other Russian towns in the lower Chu Valley by a flood from the lake. When the ends of the canal were opened, the water ran in both from the lake and from the river, but the current from the ri\'er overcame that from the lake, and since then the flow has been into the lake. He added that the originally straight canal has become winding by ^'^- ''-'!^^^:J^^S;^t^'- the action of the stream. Still a third account is that the Kirghiz found the lake was slowly rising on their fields, and that they cut a canal to the river, hoping thereby to lower the water. It is \erA- doubtful whether there is any truth in these stories. In 1856 Semenof saw a small marsh at the elbow of the Chu, from which a tiny rivulet flowed to the lake (1869, 322). A little later, Venyukof noted the winding course of the Kute-maldy and considered it a natural bifurcation of the Chu (i860, 395). In 1859 Golubef described the Kute-maldv as an artificial canal. " The water in it is nearly stagnant, and barometrical leveling did not show any perceptible difference between the levels of the lake and the Chu " (1861, 369). Osten-Sacken saw the Kute-maldy in 1867 as a shallow, sluggish, winding, muddy stream, with a delta at its mouth (1869, 28). The last description applies to the stream as we found it in 1903. Its channel is said to be left nearl)- dry wheu the water in the Chu is low. In view of the delta-like form of the gravel plains between the present course of the Chu and the lake, there is no sufficient reason for susjiccting that the Kute- maldy is anything but a natural distributary- of the main river, from which it can hardly divert more than a twentieth part of its volume. It is interesting to inquire what effect would be produced on the lake if the whole current of the Chu were turned into it, and for this purpose the following numerical data are] pertinent. According to the 40-verst Russian map, Issik Kul 112 EXPLORATIONS IN TURKESTAN. occupies about two-fifths of the total area of its catchment basin, the upper Chu basin not included. The surrounding mountains, from which most of the water sujiply is received, proba1)ly occupies as nnich surface as the lake, leavinj^ one-fifth of the catchment basin as valleys and piedmont slopes. The drainage basin of the upper Chu system, southwest from the lake, is in area about a quarter of the present Issik Kill basin, or roughly a half of the mountain area that drains into the lake. Inasmuch as the chief upper branches of the Chu, the Kach-kar and the Juvan- arik, come from among high ranges, it is evident that their volume nuist be a considerable fraction of the total water supply that tlie lake now receives ; not, however, so large a fraction as their drainage area would suggest, for the mountains southeast of Issik Kul are lofty, and we were told that many large streams flow from them. If liberal allowance be made for this, the upper Chu might be taken as yielding perhaps a twentieth of the present supply of Issik Kul ; hence if the upper Chu were turned into the lake, its surface ought to expand by a twentieth part, if it did Hot overflow to the lower Chu before such an expansion was accomplislied. On the other hand, when the lake stood at the 25-foot shoreline, its area could hardly have been increased by a twentieth of its present surface. Hence it is probable that if the Chu should now be turned into the lake, its surface would rise to the 25-foot shoreline, if a barrier of that height existed at the outlet; and there might be some water to spare for overflow. It has already been shown that the delta-like plains between the Chu and the western end of Issik Kul indicate that the river has entered the lake. Evidence will now be presented to show that an overflowing outlet has prob- ablv generally existed during the subrecent histor\- of the lake. This evidence is found, first, in the eastward increase in tlie depth of valley erosion, and, second, in the eastward increase in the depth of valley drowning, already stated. To appre- ciate this curious case, a preliminan,- statement will be serviceable. The problem before us is to discover the conditions under which a lake, A B, (figs. 77, 78) may preserve its shoreline at A nearly constant, while it sinks from B to D (E) and rises from D to G (H). Let us first inquire how such changes can be produced in a lake without an outlet. Let the area of the lake, A B, be such as to strike a balance between the rainfall on its entire drainage basin and the evaporation from its surface. If the climate remain constant and regional tilting occur, with uplift on the right, as in fig. 77, the lake will sink from B to D and rise from A to C, thus preser\'ing its area unchanged. In order that the shoreline .shall remain at A during uplift, the climate must become just enough more arid to reduce the lake area so that its surface shall be E A, instead of D C. On the other hand, if depression occur on the right, as in fig. 78, the lake will change from A B to F G. In this case the shore can be held at A only by climatic change towards more humidity of just such amoxmt as to expand the surface to H A. It is Fig. 77. — Effect of tilting on an in- closed lake ; uplift on the right. Fig. 78. — Effect of tilting on an in- closed lake; uplift on the left. RELATIONS OF THE RIVER CIIU TO ISSIK KUL. II3 evident, then, that the maintenance of the lake shore at A in a lake without outlet involves an extremely improbable correlation of two independent processes — a balancing- or tilting of the region and an external climatic change. Hence a lake in which the shoreline remains nearly fixed at A, while it sinks to D (E) and rises to G (H), must in all probability be unlike the lake here postulated ; that is, it must be provided with an outlet, instead of being without one. It is plain enough that an ov-erflowing lake will keep its shoreline fixed at the outlet, however much it may change elsewhere on account of a tilting of its basin. Hence there can be no cjuestion that the recent valley erosion and valley drowning around Issik Kul are Ix'tter accounted for by the example of a lake with, and not without, an outlet; and it therefore seems reasonable to conclude that the present relations of the Cliu to Issik Kul is exceptional, and tliat the river lias generally flowed into and out from the lake. Under such conditions it may well be that the overflowing river was a comparatively small one ; and it is possible that the heavy valley deposits, now dissected, in the Chu Valley for the first 20 miles west of Issik Kul were accumulated there at a time when the river was too weak to sweep them away, as well as because of the block faulting of the neighboring ranges, as suggested in an earlier section. Indeed, there is a point about 5 miles west of Issik Kul where the fans from the range on the north would close the outlet valley, or raise its floor 100 or 150 feet o\'er the present lake, if their slope were continued forward from their now dissected mass ; and it may be that when these fans were formed Issik Kul temporarily had no overflow. We are thus led to think that Issik Kul has generally had a water supply sufficient to cause overflow during the snbrecent time of the erosion and the drowning of the valleys in its surrounding slopes of piedmont waste, and that the Chu has frequentl}- or usually been an aflSuent of the lake ; also, that the fall of the lake from its 25-foot shoreline to its present level ma}- be explained, in good part at least, by the diversion of the Chu past the west end of the lake, as well as by climatic change. It might be possible, by means of soundings, to extend the time to which these inferences apply, so as to include the earlier period in which the piedmont slopes and the eastern plain were aggraded. It is, on the other hand, probable that the outlet of the lake may often have been of so small a volume that it ceased to overflow during arid epochs of secular duration, as well as during dry seasons. It is quite possible that the present era of desiccation may be of the former character, and in this connection it is noteworthy that, according to Schwarz, the level of Issik Kul was lowered b)- 2 meters from 1867 to 1877 (1900, 581). It should not, however, be forgotten that the inferences here offered are tentative. The history of the lake is evidently too complicated to be deciphered in a week's visit to part of its shores. It is a most inviting field for further study, and all the more so when its relation to human settlement is considered, as will appear in a later section. 114 EXPLORATIONS IN TURKESTAN. NOTES ON ARCHEOLOGY. Brief mention has already been made of the mins and mounds on the plains. They arc fnrthcr considered in reports by other members of the expedition. The following notes concern localities that were visited on the jomney from Andizhan to Issik Knl. MOUND.S ON THE (EASTERN) KUGART TERRACE. Near the tenninal mass of the great landslide of the (eastern) Kngart, on the high terrace plain over the Kirghiz bridge, we saw 20 to 30 small mounds, from 20 to 25 feet in diameter and from 3 to 5 feet high, made mostly of earth, with cobbles from the terrrace and small angular blocks from the landslide. Smaller mounds, from 5 to 8 feet in diameter and 4 feet in height, were made wholly of stones. No chipped stones were found near them. No such mounds as these were seen in the summer camps of the Kirghiz, and hence we ascribe them to some earlier people. STONE CIRCLES NEAR SON KDL. On the gently inclined piedmont slopes that descend to the OO^ southeast shore of Son Kul, a mile or more from the lake, we found Q. a row of stone circles. Our guide said they marked the camp of ^° a powerful khan who iised to occupy this district, but the Kirghiz ^^ o_ are not to be trusted in such matters. The circles were nine in § a5 number, unevenly spaced, but set on a nearl}- north and south line, /« bearing N. 8° W. magnetic. They are 11 or 12 feet in diameter, o<^ each one containing eight stones from 3 to 5 feet in diameter, all O^O s? of granite from the mountains a mile or more to the south. 9s The fourth and eighth circles have been disturbed. The general qq _Q arrangement of the stones is indicated in fig. 79, which shows the Q n "^ lateral displacement of the fourth and fifth circles, and indicates '^ •*'' the distance between the successive circles, as determined by pacing. ^ Q A standing stone, rising 4 feet above the ground, is set in a O*^ as 15-foot circle of small stones, 60 feet east of the ninth circle. o* *^ North or northeast of the row of circles, 28 small gravel mounds ^c5^°'''' occur within a few hundred feet, and a 5-foot standing stone is O OO seen by the trail 500 or 600 feet to the west. A mile or more to ^ O 42 the east there are several earth mounds, 5 or 6 feet high and from i^^'Zi 30 to 50 feet in diameter. Four of them are nearly on a N. 12° W. '^o cp^ (magnetic) line. The others are placed irregularl)-. No chipped p. ^g _sione C stones or flakes were found by anj- of the circles or mounds. Two near Lake Son Kul. standing stones on a mound on the plain northeast of Son Kul b^tt^n'the arel^u have human faces rudelv carved in outline on a flat surface. Regel indicated in figures on ,,._..,' the right. makes mention of similar monuments (1879, 414). NOTES ON ARCHEOLOGY. I 15 OLD CANALS NEAR SON KUL. The well-grassed foothills of the Kok-tal range north of the Son Kul outlet bore the marks of ancient irrigating canals that gave us much surprise, as the region does not suffer from dryness to-day. The abundant pasture on the foothills and the piedmont slopes is testified to b}- the great number of cattle driven up there for the summer by the Kirghiz. The canals are now almost obliterated, yet they are indubitably of artificial origin. The Kirghiz seemed to know nothing about them. They have been so far filled by the creeping of waste from the upper slope that they appear as benches 5 or 10 feet wide, instead of as channels. They lead with gentle descent from a stream along a hillside at different levels. Gullies, more or less grassed over, often descend the slope below the canals, marking the paths of accidental o\-erflows. Similar nearly obliterated canals were seen on one of the northern spurs of the Kok-tal range as we descended from the Kum-ashu Pass into the Tuluk Valley. Their course was observed to better advantage the next day, when we stood on the large moraines on the north side of the valley and looked across to all the spurs on the other side at once. Three canals were then seen on one spur at different levels. The uppermost, estimated to be 700 feet above the Tuluk-su, pa.ssed around the ridge line of its spur and turned into the next ravine on the east. Another one on a neighboring spur ran out to the spur ridge, and then followed down the ridge into the main valley. As on the other side of the range, these old canals all started at a stream and led forward on the side of a spur, and down-slope gullies from the canals frequenth- marked the paths of overflows. THE ISSIK KUL DISTRICT. The car\-ed standing stone, shown in fig. 80 was photographed by Mr. Hunt- ington on the plain at the east end of Issik Kul. The following notes are from the same observer. Walls or mounds are found at ten or twehe places on the fertile piedmont plains northeast of the lake. They are generally arranged in lines run- ning roughly north and south. Those that were examined consisted of a circular or oval wall of cobble stones, from 10 to 30 feet high, covered with earth. In the smaller examples the center also was filled with earth, so as to fonn a mound. In the larger examples the center was unfilled, and fonned a hollow within the wall. The only clue as to the age of these monuments in relation to the history- of Issik Kul was furnished b\- a small mound, 14 miles east of Sazanovka. The mound in question stands on the edge of the bluff, the base of which has been cut back by the 30-foot shoreline (the same shoreline is at 25 feet over the lake farther west), and the edge of the mound has thus been cut back so that one-third of its area is under- mined and lost. The cobbles and bowlders of which the wall of the mound was made are scattered at the base of the bluff It would thus appear that the mound- builders lived around Issik Kul before the 30-foot beach line was abandoned by the lake. ii6 EXPLORATIONS IN TURKESTAN. The occurrence of ruins beneath the lake waters was noted b)' Semenof in his journey in 1857. He was told of the remains of an old city under the lake, about half a verst from its northeast shore (1858, 360). Other travelers make similar reports, but nothing definite seems to be known. We were shown a square brick, about 10 inches on a side and 2 inches thick, that was said to have been dredged from these ruins. Mr. Hinitington was told, on the good authority of General Korolkof, at I'rzhevalsk, that the ruins can now be .seen on the lake ])ottom "in Fig. 80. — A Carved Stone on the plain at the east end of Issik Kul. looking south. water of considerable depth." There is no direct evidence to determine the date of the jjeriod of low water during which the houses now submerged were built; but Mr. Huntington points out that brick houses are presumably of more modem constniction than cobblestone walls, and hence that the submerged houses were probably built during a low-water stand, after the high-water stand recorded in the 30-foot beach. The fact that the bricks can be seen on the lake bottom, not yet buried bj- silts, points to the same conclusion. The lake ought to be carefully sounded and dredged. CONCLUSION. I I 7 CONCLUSION. Many problems that are touched upon in this and the following reports deser\-e much more study than we have been able to give them thus far. Some of them bear directly upon the objects of our expedition ; some are of general interest. Of the first class, the oscillations of the Caspian stand preeminent, and the desert depression, known as the Ungus, seems to be the most important district for next examination in this connection. In view of what is known of climatic variations during Quaternary time in other parts of the world, it is hardly possible that the Aralo-Caspiau history is of only one expansion; and whatever complications it experienced would probably have left their record on the bluffs and slopes that border this desert depression. At the same time, the confirmation of our conclusions regarding the complexity of the Glacial period b}- further study of moraines and terraces, especially in the Alai ranges and the Pamir, is much to be desired. Then would come the connection of these two classes of unlike records — lacustrine and glacial — by aiu- means that can be devised, along the mountains on the south or across the desert plains, thus gaining a correlation of the events of Quaternary time in the three physiographic provinces of the western Asiatic region and bringing the archeological remains of the plains into their place on the geological time-scale. Of subordinate value, but by no means unimportant, are the problems connected with the deposits of loess. Those south of Jizak deserve first attention. Issik Kul is a problem by itself Geology, physiographj-, and archeology- are there combined in the most inviting manner. A long season in that field alone would be highly productive. .Vn outstanding problem of importance in its bearing on theoretical geolog)' is found in the structure of the Tian Shan ranges. For this purpose the region could be entered to ad\-antage from the north, and a deliberate stud}- made of the pene- plains and fault-block mountain ranges o\-er which our party had to pass so rapidly. Few finer fields are open to the investigator. Il8 EXPLORATIONS IN TURKESTAN. LIST OF REFERENCES. The following list of authors and articles makes no attempt to include all that has been written on Western Asia, but only to present those essays that bear most directly on the problems here discussed. The list is, however, unfortunately incom- plete in many respects, inasmuch as the libraries accessible during the preparation of this report have been found deficient in regard to Russian explorations in Asia. The names of Russian authors cited are turned into English phonetic spelling. The sch, tsch, and dsch of the German transliteration and the soft ch of the French are avoided, unless the article cited is in German or French; in that case the published transliteration is given in parentheses. The terminal tch, which is so generally used, is continued instead of the English hard ch. English translations of Russian titles of articles are inclosed in parentheses. G. V. Almasy. Reise nach West-Turkestan imd in den centralen Tienshan. Mitt. k. k. geogr. Ges. Wien, xliv, 1901, 239-261. N. I. Andrusof. (Sketch of historical development of the Caspian Sea and its inhabitants: in Rus- sian). Isvestia Imp. Russ. Geogr. Soc, xxiv, 1888, 91-114. (.\ndrussow). Beitrage zur Kenntniss des Kaspischen Neogen: Die Aktschlagylschichten. Mem. Com. Geol. St. Pet., xv, No. 4, 1902. K. I. BocD-\NOviiCH. Compte rendu prelirainaire sur les reeherches orogeologiques dans la partie imontagneuse de la region transcaspienne et des provinces boreales de la Perse (French title and abstract in original Russian article). Bull. Com. (ieol. St. Pet., vi, 1887, 66-104. E. BRticKNER. Klimaschwankungen seit 1700. Penok's Geogr. Abhandl., iv, 1890, No. 2. G. Capus. a travers le royaume de Tamerlane. Paris, 1892. M. Friedrichsen. Morphologic des Tien-Schan. Zeitschr. Ges. Erdk. Berlin, xxxiv, 1899, 1-62, 193-271, map. Beitrage zur morphologic des zentralcn Ticn-Schan. Pet. imitt., xlix, 1903, 134-137. G. K. Gilbert. Report upon the geology of portions of Nevada, Utah ... in Report upon geo- graphical and geological explorations and surveys west of the one hundredth meridian (Wheeler's Survey) : Vol. Ill, Geology. Washington, 1875. A. GoLUBEF. Brief sketch of the results of the Issik-kul e-xpedition (translation). Journ. Roy. Geogr. Soc, xxxi, 1861, 366-370. The same in German in ErmaJi's .\rchiv., xx, i860, 20-37. A. M. KoxsHiN. (Preliminary report on the results of geological and physiographic investigations in the Turkomanian depression: in Russian). Isvestia Imp. Russ. Geogr. Soc, xxii, 1886, 379-439. (Konschin). Gcologischer Ueberblick Transkaspiens. Pet. Mitt., xxxiii, 1887, 226-244. (The ancient course of the Amu darya: in Russian). Sapiski Caucas. Division, Imp. Russ. Geogr. Soc, xv, 1893, 1-21. Abstract in Ann. de Geogr. v, 1896, 496-504. (The ancient course of the Amu darya: in Russian). Sapiski Imp. Russ. Geogr. Soc, xxxiii, 1897, 1-256. P. Lessar. L'ancienne jonction de I'Oxus avec la mar caspienne. C. R. Congr. internat. geogr., Paris, i, 1889, 706-727. I. V. MusHKETOF. (Turkestan : geologic and orographic description from data gathered during journeys in the years 1874-1880: in Russian). Vol. I, St. Petersburg, 1886. (Muschketof). Das Erdbeben von Wernoje vom 28 Mai, 1887. Mem. Com. Geol. St. Pet., x, 1890, 141-154- (Short sketch of the geological formation of the Transcaspian region: in Russian). Proc Imp. Russ. Min. Soc, 2 sen, xxviii, 1891, 391-429, map. • (Physical Geology: in Russian). Vol. I, St. Petersburg, 2d ed., 1899. M. Neumayr. Die Aralo-Kaspi Niederung. Verhandl. k. k. Reichsanst., 1875, 31-33. V. A. Obruchef. (The sands and steppes of the Transcaspian region: in Russian). Isvestia Imp. Russ. Geogr. Soc, xxiii, 1887, 174-190. (The trans-Caspian depression : Geologic and orographic sketch from data collected during an excursion in i886-'87-'88 : in Russian.) Sapiski Imp. Russ. Geogr. Soc, xx, 1890, 1-260. AUTHORS AND ARTICLES CITED. II9 Fr. v. d. Osten-Sacken and F. J. Ruprecht. Sertiim Tianschanicum. Botannische Ergebnisse einer Reise im mittleren Tian-Schan. Mem. Acad. Imp. Sci. St. Pet., 8 ser., xiv, 1869, No. 4. N. G. Petrusevitch (Petrussewitsch). Die Turkmcnen zwischen dem alten Bett des Amu-Darya (Usboi) and der Nordgrenze Persiens. Zeitschr. wi.ss. Geogr., i, 1880, 194-202. A. Phiuppsom. Das russische Flaohland. Zeitschr. Ges. Erdk. Berlin, .xxxiii, 1898, 37-68. A. Regel. Reisen in Central-Asien, 1876-79. Pet. Mitt., xxv, 1879, 408-417. E. Richter. Geomorphologische Untersudiungen in den Hochalpen. Pet. Mitt Erganz'h, No. 132, I goo. V. RoBOROVSKV. Progress of the Russian expedition to Central Asia under Col. Pievtsoflf (transla- tion). Proc. Roj'. Geogr. Soc, xii, 1890, 19-36. G. St. h'ES. Dans le Tian Chan russe. Ann. de Geogr., vii, 1898, 201-215; ix, 1900, 119-140. F. V. SCHWARZ. Turkestan. Freiburg i. Br., 1900. P. V. SemEnof (Semenow). Erforschungsreisen in Inner-Asien im Jahre, 1857. Pet. Mitt., 1858, 351-369- Narrative of an exploring expedition from Fort Vernoye to the western short of the Issik- kul Lake (translation). Journ. Roy. Geogr. Soc, xxxix, 1869, 311-338. N. Severtzof (Sewerzow). Erforschung des Thian-Schan Gebirgssystems, 1867. Pet. Mitt., Er- ganz'h., No. 42, 1875. G. SiEVERS. Die russische Expedition naoh dem alten Oxus-Bette . . . 1872. Pet. Mitt., xix, 1873, 287-292. H. SjoEGREN. Om aralokaspiska hafvet och nordeuropeiska glaciationem. Stockholm Vet. Akad. Forh, xlv, 1888, 155-167. E. SuESS. La Face de la Terre (Das Antlitz der Erde), traduit . . . sous la direction de Emm. de Margerie. Paris, I, 1897; II, 1900. G. Tarnowski. Bericht uber das transkaspisciie Gebiet, 1891 und 1892. Askhabad, 1893. Noticed in Pet. Mitt., Lit. Ben, xli, 1895, 100. M. Venyukof (Wenjukow). Bemerkungen iiber den See Issyk-kul und den Fluss Kosch-kar. Erman's Archiv., xx, i860, 388-399. A. VoSNESENSKY (Wosnessenskij). Ueber das Erdbenben in und um Wernyj im Jahre 1887 und ihre Beziehung zu meteorlogische Vorgangen. Repert. f. Met., xii, 1888, No. 4. J. Walther. Das Oxusproblem in historischer und geologischer Beleuchtung. Pet. Mitt., xliv, 1898, 204-214. » • Das Gesetz der Wiistenbildung. Berlin, Reimer, 1900. G. F. Wright. Recent geological changes in northern and central Asia. Quart. Journ. Geol. Soc, Ivii, 1901, 244-250. E. Yakoflef (Jakowlew). Zur Geologic der Aralo-Kaspischen Niederung (mitgetheilt von G. v. Helmersen). Bull. Imp. Acad. Sci., St. Pet., xxviii, 1882, 364-376. Physiographic Observations Between the Syr Darya AND Lake Kara Kul, on the Pamir, in 1903. By RAPHAEL W. PUMPELLY. 121 Physiographic Observations Between the Syr Darya AND Lake Kara Kul, on the Pamir, in 1903. By Raphael W. Pumpelly. DESCRIPTION OF THE ROUTE. Fergana forms the southeastern extension of West Turkestan. Its southern half, the Pamir, is, so to speak, the corner stone between the Russian and English possessions and between China and Afghanistan. The district of Fergana is naturally divided into five parts. On the south is the high plateau of the Pamir, with its gra\- desert steppes and snow-clad mountain ranges, its dark lakes and ^ t ,•■■■•■ - — - y 1 ■5' U ^ O- ^^^^S CHINA /y. Karakul 7 ^''^-■~\ ( • v---''],"U. -''\ -< -^ * « jc H A ly ^ / A- "N .y AFGHANI STAN ( \ BRITISH POSSESSIONS Scale so iOO 200 300 mQes / / Fig. 81. — A Skeleton Map o( Fergana. its few long, crooked streams. Bordering this plateau on the nortli is the long, white, east-west range of the Trans-Alai, with the great snow fields and snake-like glaciers of its northern flank, abniptly ending in the broad green lawn of the Alai Valley. Separating this lawn from the lowland plains of tlie north is the complex mass of the Alai Mountains, with its irregular snow crest running east and west, but its northern flank broken into many flat-topped masses. Lastly are seen the 123 124 EXPLORATIONS IN TURKESTAN. broad gray steppes of the northern half of Ferj^ana, patched with a mnltitude of green oases, and sharply bounded on the south bj- the high, grassy slopes of the Alai range foothills. (See figs. 8i and 82.) It had been planned that the reconnaissance trip should extend to Andizhan, at the end of the Trans-Caspian railroad. On June 23 we had left Tashkent, and on the 24th our car was running along the low region just south of the Syr Darj-a. There the oases were more frequent than farther west, and the landscape corre- spondingly cheerfid. We crossed long stretches of barren, gravelly steppes, but were rarely out of sight of picturesque villages and patches of cultivated land, with their hedges of tall, shaft-like poplars agaiiLst the sky. It was decided to follow the ancient Taldic route as far as the core of the Alai range. We drove from Andizhan to Osh, the great starting point for caravans. Fig. 82. — Map of the Pamir, taken from Sven Hedin's Map. There it was decided to go to Lake Kara Kul, on the Pamir. Two or three flays were taken in making the preparations necessary for so extended an expedition, and it was the last day of Juue when our caravan left Osh for the mountains. We were to follow the old route up to the Taldic pass across the Alai Valley, up a stream to Kizil-Art pass, and thence to Kara Kul. From the lower plains of Fergana (1,200 feet) to the foothills of the Alai range (4,000 feet), there is a gradual ascent and nonnal progressive increase of natural vegetation. Even at Osh we had begun to miss the striking desert conditions of the regions below, and at Gulcha the hills were covered with rich green grass, small streams rising among them. From Takka pass there was a splendid view over a broad gulf of these green hills and \-alleys, ending in the snow-clad peaks of the Alai, 40 miles to the south. There were kibitkas (Kirghiz felt tents) here and there on the slopes, and by them herds and flocks. The Kirghiz winter in PHYSIOGRAPHIC OBSERVATIONS. 125 these lowland valleys and in the sprinj^ the\- sow great fields of grain, leaving men to tend and irrigate them, and on their return from the summer pastures reap their crops. We camped over night at Ciulcha, July 1-2. It rained heavih' during the night, and the temperature stood at 54.5° F. at 6 a. ni. Leaving Gulcha, we fell in with a long Kirghiz caravan, on its way to the Alai Valley. It was very gay, yet full of pomp and dignity. Each group was headed Fig. 83. — A Kirghiz Caravan on its way lo the Alai Valley. by the men driving their herds of cattle, horses, and camels, and their flocks of goats and sheep. Behind them came the women, all attired in their best, some in cloth of gold or silver, and ornamented with jewels. They rode in single file, each on a stallion draped with brilliant embroideries, and each leading two or more camels laden with the household goods, and draped over all with carpets of rich design. Such is the wealth drawn from the fertile pastures of Fergana. (See fig. 83.) All day we contiiuied winding up the \alley, frequently fording the stream. There were at first no trees on the hillsides, but frequent groups of picturesque mountain willows and crooked poplars along the edge of the stream (fig. 84). No wild animals were seen ; only a few vultures and flocks of pigeons vers- like our do- mesticated variety. Toward the end of the da)- we entered a granite gorge and rode a long time above the roaring torrent. Occa- sional glimpses of the slopes high up above the canyon showed thin forests of bushv cedar trees. Our camp tiie night of July 2-3 was at Suph Kurgan, where the trail forks, one branch leading over the Taldic pass, the other over the Terek Da van. During the sunnuer there is but little snow on the Taldic, and that route is used when the Terek is impassable, owing to high flood. In winter the streams are shrunken and the Terek is the best route. That night it rained heavily. Temperature at 6 a. m., 40° F. The ne.\t day we were still winding up the valley, sometimes along the stream-bed, sometimes along the top of the canyon. A new variety of foreground Fig. 84. — A Poplar Tree in the Taldic Valley. 126 EXPLORATIONS IN TURKESTAN. was ffiven at c\-cr\- turn, and the ever-changing clouds gave new and more charming effects on tlie high peaks iu the distance. We were in the ;\lai range, for glistening snow peaks appeared above the green hills on botli sides, wliilc in front there rose a chain of gigantic snow-clad p\ramids, partially hidden 1j\' the clouds that streamed from their summits. From Suph Kurgan to the Taldic pass the mountain sides are dotted witli scrubby cedar trees, which grow smaller, more crooked, and more picturesque as the altitude increases, and below the pass exist as mere stunted spreading bushes hugging the slopes. When about 15 versts below Ak-Busa-Ga we heard, for the first time, the shrill whistle of the marmot, and from there to the border of the Pamir desert this was the characteristic wild animal. At a little after 3 in the afternoon our caravan came to where the valley opened out on the broad, grass- Fig. 83. — Looking up the Taldic Valley at the Entrance to the Broad Plain of Ak-Busa-Ga. covered flood-plain of .\k-Busa-Ga (figs. 85 and 86). There we camped over night. At 5.30 p. m. the temperature was 40° F. At 9.30 p. m. it had fallen to 32° F., and it was snowing heavily. The next day, July 4, the caravan made an early start, for we were to cross the Taldic. It was a clear, frosty morning, with the white snow peaks above glistening in the sun. In about a verst the broad valle)' changed to a torrent canyon. Beyond it opened out again in grassy slopes, where many Kirghiz families had pitched their kibitkas (fig. 88). Flocks of sheep and goats, herds of cattle and horses, and many wandering groups of two-humped camels were grazing b)- the trail. .Above were high peaks, some of craggy rocks and others more heavily covered with great sliding banks of snow. Delicate, steaming clouds trailed from the summits, and others appeared over the ridges, rolling up from the opposite side. One cloud swept down the valley for a moment, its refreshing moisture blowing against our faces. Ahead of us we could see where the trail makes its many zigzags before PHYSIOGRAPHIC OBSERVATIONS. 127 reacliiny the pass, and our horses were soon strugj^lino- tip the steep slope past countless skeletons of unlucky pack animals that had fallen in the effort. The clouds gathered .so rapidly that the pass, the elevation of which is 11,600 feet, was in a sea of mist when the summit was reached. On the southern side the snow Fig. 86.— Ak-Busa-Ga. was much deeper and the drifts so heavy that our guides had difficulty in remaining on the trail, but a short descent led us below the snow-line and down to Sari Tash, on the edge of the Great Alai Valley. There we halted for a day to rest the horses. The Alai Valle}', as it is first seen (fig. 87), looking across from the foothills at Sari Tash, is one vast expanse of smooth green lawn, abruptly bordered on the south by a magnificent wall of snow-clad inouutaius, and extending east and west nearly as far as the eye can reach. It is 75 miles long, averages 15 miles in width, lies Fig. 87. — Looking across the Alai Valley to the Trans-Alai Mountains. Taken from a peak north ol Sari Tash. 10,000 feet above the sea, and is walled in by the Alai anil Trans-Alai mountains, two of the lofty ranges of the world. For nine moutlis of the year snow several feet thick lies upon it. Then it is void of humau habitation, and the wolves hunt undisputedly the wild sheep and ibex. By the beginning of July this snow has melted. Like magic the grass turns green, the poppies and buttercups bloom, the marmots come out to sun themselves and call in shrill notes to one another, and. 128 EXPLORATIONS IN TURKESTAN. the Kirjjhiz, with their vast herds and flocks, are pouring over the passes on to the rich pasture. There are no trees, no bushes, nothing but a world of grass sprinkled with beautiful wild flowers. It is said that Mount Kaufnianu is rarely free from its canopy of clouds, but we had a fine view of it during our first stay in the valle}-. From over the spur at Sari Ta.sh it came in sight, a long ma.ss of ridges and amphitheaters rising in groups one above the other, and above them great snow-fields mantling the cliffs. Here and there we could see a glacier starting in a group of cirques below the top, and pouring forth its snake-like river of ice to the very edge of the plain. It was a grand siglit, this gigantic complex of ridges and snow-banks rising to the top Fig. 88.— The Kirghiz in the Alai Valley. peak of all, an ice-capped pyramid so high that it creates the clouds and directs the storms. For a long time we saw the clouds, blowing up from the northwest, split on Mount Kaufmann, part turning back to the northeast, collecting on the Alai range behind us, while the rest formed a horizontal stratum floating just below the high peaks of Mount Kaufmann and disappearing southwest over the Pamir. By the end of the afternoon it began to thunder and hail on our side of the valley, but during the whole storm the sun shone brightl)- on the Trans-Alai Mountains, and we could see them sparkling through the hail. Temperature at 7 p. m., 39° F. On Jid}- 6 our caravan crossed to Bor Daba, on the south side of the Alai Valley, and camped there over night. When we arose at 5 a. m. on the 7th it was 35° F., and the stream was sheeted over with ice. The sky was clear, the mountains PHYSIOGRAPHIC OBSERVATIONS. 1 29 free from clouds, and tlie rose tints of sunrise were fading away from the snow- fields of Mount Kaufmanu. There was a long journey before us over Kizil-Art pass to Kara Kid. The trail follows along the edge of the Kizil-Art darya to the pass. The snow had melted to its perpetual line, leaving a few masses of white forking down into the ravines. The landscape was everj'where characterized by an extraordinary- richness of coloring, especially the deep red of bare g\psum rocks forking into the soft green of grassy slopes, and above them a deep-blue sk}-, broken here and there by silver)' clouds. Always cutting our view in twain was the deep valley of the ever-roaring torrent along which we rode. In places this valley narrowed to a canyon, and the trail led us above, where we looked down into depths from which the sound of roaring water could barely reach us. When about 12 versts from Bor Daba we sighted a flock of takkan (ibex) grazing on the thin grass of a side fan, and a little farther along, on a distant ridge, five Marco Polo sheep {Ovis poll), standing one behind the other, and clearly out- lined against the sky. Farther up the valley the green slopes gave way to barren red, streaked here and there with drifts of snow. On all sides rose massive spurs of deep red, sharply carved into parallel ravines running straight down the slopes and crested with dazzling snow outlined above against a sky of turquoise blue. At about II a. m. the caravan reached Kizil-Art pass, 13,721 feet above sea level (by recent Russian leveling), where we stopped to rest the animals. They had carried us 20 versts o\-er a rough trail and up 3,000 feet in four hours, and e\-en the strongest were panting hard from the rarefied atmosphere. Looking back we coidd see the deep valley out of which we had climbed. Its dark bottom seemed to reach a depth even greater in perspective than the height of the mountain above us. Here I left the caravan, and while it went on down to Kara Kul I climbed on foot the first peak to the west. This was an excellent position from which to compare the forms established by erosion on the north and south sides of the Trans-Alai crest. On the north the slopes began by sinking into broad amj^hi- theaters, and beyond fell rapidly into deep valleys and dark ravines, separated by high, irregular spurs of soft gypsum and sandstone. On the south, the Pamir side, there seemed to be no great descent ; long, straight spurs extended transversely from the main mass, and between them lay flat plains of gravel, starting in the cirques just below the crest and inclining gently toward the south. We had expected to find the region about Kara Kul like the Alai \'alle\-, green with grass ; in reality the two could hardly be more diflferent. From the high slopes of the pass, wet from melting snow, the trail led to a Avy steppe of gravel extending nearly as far as the eye could reach. In a few \-ersts the stream wander- ing on its surface dwindled away, leaving a drj' bed. One could perceive nothing living. Here and there projected piles of bowlders hollowed, pitted, and polished by the sand. All along the trail were the bleached bones and skeletons of pack animals that had probably died under loads. After a seemingly interminable ride along stony steppes, pa.st barren talus- shrouded mountains, and over large, incgular piles of moraine, the desert basin of I30 EXPLORATIONS IN TURKESTAN. Great Kara Kill came in view (fig. 89), and we reached a point where the trail begins a rapid descent into the basin and a corner of tlie lake appeared. Far and wide stretched the same monotonons, dazzliny; gray, unbroken by anv sign of life or vegetation. A little way to the right there rose a talus-shrouded mass of rock, and in front were crooked, hollowed bowlders with sharp shadows, while in the distance, far below, was the black-blue sheet of Kara Kul reposing calm and silent, with its deep color contrasting strangely with the monotonous, dazzling gray of the gulf-like desert in which it rested. All around this lifeless waste there rose a continuous chain of snow-clad mountains with their sharp peaks and ridges outlined against a clear blue sky. It seemed like a lake that had lived and died long ago, and now reposed in its desert gra\-e under heaven's ethereal blue and Fig. 89. — Looking down the Kara Kul from Uy Bulak pass. among the guardian white mountains, ever watching, ever keeping the unbroken silence of space. From time immemorial this barren desert has been called The Roof of The World, and the name seemed appropriate, for the mountain borders shed their waters to lands of diverse and powerful nations. There, on that eastern crest, was the boundary- of China, to the south were the British, to the west the Afghans, and here it was Russian laud. The caravan had camped on the northeastern shore of Kara Kul. There we remained over the ne.xt da)- to stud)- the desert. Imagine a ground of split and polished stones which stretches awa)' in a seem- ingly endless waste, the little relief and variety of projecting rock masses near by fading beyond to drear)- flatness. That is the Kara Kul desert. There are no trees, no bushes — in fact, no familiar forms by which one's puzzled e)'e can scale the PHYSIOGRAPHIC OBSERVATIONS. 131 distance. In tlie distance, a silver\' sheet of water reflects and dances on the plain. For a moment there seem to be men and animals moving on the shore, but then the lake slides away into space, the men and animals disappear, and there, instead, is the mocking plain. A far-off dust colunni appears on the horizon. At first it seems motionless, but soon there is a visible movement as it approaches, growing denser and taller, and turning, it rapidly crosses the steppe with an irregular motion. It may fade away in the distance ; it may disappear suddenly in some unexpected place. These dust storms tell a storj'. During the warm hours of the day there is nearly always one, often there are two or more in sight. The desert surface here shows a Fig. 90. — Deflated bowlder of granite. Fig. 91. — Deflated bowlder o( granite, hollowed side facing east. Taken at 10.30 a. m. Fig. 92. — A talus-shrouded mass of crystalline limestone. Fig. 93. - A glacial bowlder of crystalline limestone cracking from the changes of temperature. remarkable lack of loose, fine material. But tlie inclosing mountains are largely made up of rotten g^-psum and limestone with earthy surface, from which great quantities of fine stuff are brought down during cloudbursts and left on the fans, always to be carried away by the winds and deposited elsewhere ; probably, according to Richthofen's theor}-, as loess in some neighboring zone of vegetation. Kara Kul is a lake of bitter salt water. Its sloping shores are white with salt accunuilated into low ridges where the brine from each wave-wetting has dried out after the recession. Behind some of these natural dams there are lagoons of brine collected from the overflow of larger waves, and thus, in places, extending the salt belt 100 feet or more from the shore. I could find no shells and saw no fishes. 132 EXPLORATIONS IN TURKESTAN. There was much dead tape-like grass on the shore, but as there seemed to be none fresh, it nia}- ha\-e been washed out of the gray clays deposited at a higher level, which are well matted with a similar grass (p. 139). Most of the streams rising in the melting snows of the inclosing mountains disappear in broad, stony fans extending from their base. The whole zone border- ing the mountains is thus characterized by a topography of interlocking fans, while the foot-hill rock-masses are largely buried in their own talus. For this reason the desert surface consists, for the most part, of bare steppes of small angular or sand-polished stones. In places there are flying sands, and certain areas bordering the mountains are covered witli moraine with a surface somewhat modified by the deflation which naturally occurs in this atmosphere of 13,000 feet altitude, where there is so marked a _ ..^ „ , , ,, ,, ^, . rig. V4. — Common type ot weathered bowlders. I he fluctuation of temperature from night to day light fragments strewn about it are parts of the and between sliade and sun. While we were '°""" """"■ there it went below freezing at night, but during llie day our faces were blistered by the dazzling simlight. Figures 90 to 94 give an idea of the striking forms of desert weathering. Except for a few deeply-rooted flowers in bloom and rare clumps of grass on the dry beds of streams, the Kara Kul desert is \-oid of vegetation. No man li\'es on it, and those who cross it with their caravans have difficulty in finding feed for their animals. The only wild animals .seen on the plains were a rabbit, a few ducks and gulls about the lake, and some vultures devouring the carcass of a camel on the trail. On the slopes of the bordering mountains there was more water and more life. A few mannots burrowed where the grass was thickest, but the characteristic beast was the Marco Polo sheep {Ovis poli)^ the largest of all wild sheep. Of them we saw two or three flocks, one of which numbered over fift}' sheep. After spending four days on the Pamir we recrossed Kizil-Art pass, and returning by our outward route, reached Osh again on July 17. DETAILED OBSERVATIONS. From the lowland plains of Fergana we had studied the Alai IMountains through our field-glasses, and recognized in them glacial fonns of erosion, such as amphi- theaters inclosed by sharp crescent ridges, and above them groups of cirques, and we thought we saw glaciers beneath the higher masses. Unfortunatel}', the old caravan route led us over a lower part of the range and did not bring us in contact with any records of glacial action until we reached the Alai \'alle}-. It can, how- ever, be stated that the famous Zerafshan glacier lies in a high longitudinal valley of the western extension of the Alai range, and that there are several other glaciers in the high mountains around it. Nowhere did we find any indication of a former regional ice-cap. Glacial remains with which we actually came in contact were confined to the Alai Valley, Trans-Alai Mountains, and Pamir. PHYSIOGRAPHIC OBSERVATIONS. 1 33 IN THE ALAI VALLEY. With our field-glasses we had seen from Sari Tash the great glacier on Mount Kaufmaun and large grass-covered moraines extending nearly across the jjlain from all the principal valleys along the Trans-Alai range. The morainal masses extending transverse!}- across the Alai \'alley were each made up of at least two moraines belonging to two distinct, long-separated epochs. The old moraines are broad, smoothed-off lobes made up of large and small semiangular bowlders, usually of rather hard red limestone and mixed with finer till. Their surfaces sloped gently to the plain on each side, and no undrained depressions were seen. The whole was coated with loess usually 2 to 3 feet in thickness. The identification of this loess was at first a little doubtful, owing to the presence of thousands of mannot holes, most of which reached into the till below, thus bringing a quantity- of small stones to the surface, but it was well established in exposures on stream cuts. The streams now flowing from the side valle\-s have Fig. 95. — A Ketlle-hole Lake on the Moraine extending from the Kurumdi Mass transversely into the Alai V aliey. The Trans-AIai Mountains rising into the clouds. in some cases cut broad, flat-bottomed channels in these moraines and in other cases are deflected to one side, cutting a bluff. Lying on the middle of these old smoothed-off" moraines or in the channels there are long, narrower moraines of the second epoch. In topography the\' are made up of irreg^ilar chains of steep mounds with many large blocks on the surface and frequent kettle-hole lakes (fig. 95), and near their origins are cut by sharp V-shaped torrent valleys. They seem to be made up of essentially the same material as the old moraines. They also have loess on their surfaces and are grown over with grass, but, owing to their exceedingly irregular topography, their loess coat varies in thickness e\-en more than that on the old moraines. It did not seem practicable with the little time I had to attempt to get an a\'erage measurement, but there appeared to be much more loess on the old moraines than on the new ones. Of course this might be partly due to the more exposed position of the latter. There seemed to be a third series of moraines extending a short distance from the valley mouths, and in cases overriding those of the second epoch (fig. 96). Professor Pumpelly considered them to be of a third epoch. 134 EXPLORATIONS IN TURKESTAN. Many of the cross-valleys flowing into the Alai Valley from the Trans-Alai range had the form of rounded tronghs cut down in the middle by narrower troughs, as in fig. 97. The erosion forms obser\^ed low down on the flank of the Trans- Alai, bordering the Alai Valley, are cut mainlj- in rather soft rocks, especially in partially decomposed gypsiferous series with occasional harder beds of red sandstone. i°<»S.OV Kor^^o-D- ing in its mouth and covered the inner trough bottom for some 7 versts upstream, so that, although the base is being raised by filling back of waste, the upper half of the stream has not yet recovered from some previous lowering of base and is still cutting down on rock bottom. The only tributan,- amphitheater which I had occasion to examine in this \-alley was that opposite Bor Daba, 4 versts to the west. It contains grass-covered moraine of fresh topograph) , with kettle-hole lakes. Its bottom seems to be buried beneath the flood plain where it opens into the Kizil-Art or tnink valley. There appeared to be a mass of ice hanging on the slope some 2,000 feet above. Two of the branch streams of the Kizil-Art dar\'a were seen to head in glaciers. These branch streams and their valleys appeared to join confonnabh- the Kizil-Art darya and its valle)-. The occurrence of moraine in the inner trough of the Kizil-Art Valley and the occurrence of the partial!) -buried moraine island where tlie inner trough bottom lies buried at t!ie moutli of tlie stream show that the glacial occupation of the inner trough was prolaably contemporary witli tlie deposition of the fresli moraine island. 138 EXPLORATIONS IN TURKESTAN. ON THE PAMIR. The region from Kizil-Art pass south through the Great Kara Knl l)asin is a splendid field for the study of glacial geology. All along the trail one meets with records of past glacial activity. The high mountain sides are, at frequent intervals, sharply carved into large amphitheaters and small cirques, while the plains are dotted with piles of till. From our camp at Kara Kul we could see large moraines spread in front of the principal valleys around the liasin, and with our field-glasses we clearly .saw the glaciers as they e.xist to-day, shriveled up, hanging free-ended in their great cirques below the crest. ANCIENT SHORELINES AND SEDIMENTS OF THE GREAT KARA KUI, BASIN. The glacial geologj- of the Kara Kul region was found to be so intimately associated with the lacustrine that it has seemed best to begin with a careful description of the ancient shorelines and sediments observed in the Cireat Kara Kul basin. These shorelines resolve themselves into two classes — those below the 150-foot level and those above the 150-foot level. The first class is in excellent preservation ; the second class is largely obliterated. tig. lUO. The Norlhern Peninsula ot Kara Kul. The white of the lower portion of the right half of the illustration is salt, probably CaS04. The best examples of these shores were seen on the northern peninsula (fig, 100). There are three especially well marked le\'els at about 60 feet, 120 feet, and 150 feet, respectively, above the present lake surface. Where cut in steep rock- slopes they have the fonn of narrow, inclining terraces. When followed around to more gradnalh- sloping land they are found to be broader, gently sloping, and covered with deflating fragments of slate. The slopes are marked by miniature bands of briefer action, especially from the 60-foot mark to the present shore. There they occur as delicate contours at remarkably regular intervals of about 6 or 7 feet drop, as though there had taken place a gradual intermittent recession by equal decrements. The remarkable lack of after-erosion and the general freshness of the shorelines can not be too much emphasized. The second class, or older shores, lie at about 200 feet and 320 feet. On the peninsula they are seen as rounded-off terraces encircling and breaking the slope PHYSIOGRAPHIC OBSERVATIONS. 139 of the higher portions, but entirely worn down in some places. From a distance they were seen to cut the steep slopes coming down to the lake on the west. From the eastern shore of Lake Kara Kul the land rises with a slope of i foot or less in 100, and holds this till it meets the fans from the bordering mountains, whence it rises more and more rapidly and bends up sharply at the mountain's base East Crest A East shore sediments 62 Fig. 101. — An east-west section of the Kara Kul Basin. (fig. loi). The surface of large areas between the lake and these eastern fans consists of nude, finely stratified, blue-gra\- clays. A considerable depth of these sediments is well matted with tape-like grass lying flat and varying in width from '3 mm. to 3 mm. The roots are about fj mm. in diameter, and spring from the bottom of the wide blade, the fine leaves sprouting just above them. The leaves are light brown and although ver)- thin will bear a tension of one-half ounce and are verj' pliable. The clays are, as a whole, of the finest flour, but contain minute flakes of Fig. 102. — Section of Kara Kul sediments exposed in Hillock Bluff about 100 feet above Lake. mica and here and there a layer with small angular pebbles. The lamination is ver}- perfect ; it is easy to split off pieces a foot in area and only half an inch thick, although the same piece can be cnunbled between the fingers. A large proportion of the Kara Kul sediments lie horizontal, but there are also areas of vers- much disturbed stratification where the surface is broken into irregularly disturbed mounds or little hillocks, among which deflation and wind carving have fonned miniature bluflfs exposing the structure. The layers seen in 140 EXPLORATIONS IN TURKESTAN. these bluffs showed a peculiar distortiou, being, in most cases, bent into an arch, to which tlie mound surface is concentric and confonnable in vertical section (fig. 102). While wandering among these iiillocks we suddenly came upon an elliptical lake about i ,000 feet by 700 feet, with its long axis pointing directly toward Kara Kul. Its surface was 10 to 30 feet below the level of the plain, the walls every- where extending vertically down into clear, deep water. At first there seemed to be no reason for its existence, there being no hydrographic relation with the surrounding topography. Professor Pumpelly suggested tliat " lol)cs of ice liad been buried by the sediments ; the slow melting had deprived the sediments of their support, and the roof tumbled in, probably recentU', leaving the deep pool." Perhaps a more gradual sinking of the surface, occurring as the buried ice melted, is what has gixcn these areas tlieir hillock topography and distorted stratification. Professor Davis suggested that the solution of tlie underlying .salt deposits could ha\e resulted in the same conditions. Some versts north of this region there is a moraine sloping under the Kara Kul sediments ; this could have pushed its way imder water, weighing dowu the glacial ice that carried it, while the lake depositions covered it with clay .sediments. In this way large masses of ice could be buried beneath the sediments. Fig. 103. — Moraine of the Kara Kul Basin, looking northwest on the Older Moraine. An overriding Moraine seen in the distance on the right. OBSERVATIONS ON THE GLACIAL GEOLOGV OF THE GREAT KARA KUL BASIN. The data obtained on the glacial .geology- of this basin conform very well with the glacial history in the Alai Valley. Here, also, we find evidence of two long- separated glacial epochs and indefinite indications of a third advance of little extent. The Kara Kul sediments seem to have been largely deposited between the first two epochs established. The older moraines, as seen north of the lake, are in the fonn of smoothed-ofF masses rising out of the stratified lake clays, and made up of semi-angular bowlders of crjstalline limestone, black slates, red sandstone, gypsum, granite, and greenstone. Where observed the\- were below the 200-foot level and had clearl)- been worked over by the lake, which has left numerous bars and beaches of cobbles (fig. 103). A distributary of the Kok-sai darya has cut a very broad, flat- bottomed channel through one of these old moraines. PHYSIOGRAPHIC OBSERVATIONS. 141 Overriding these older moraines there are later ones of fresh topography having many iindrained depressions above the 105-foot level, but contoured by shorelines from this level down. No sediments were seen on these later moraines. About 5 versts northwest of the isthmus joining the north peninsula to the mainland we had the best opportunity to study the relations of the moraines to each other and to the Kara Kul sediments and shorelines. This locality includes a por- tion of the long, high, frontal bluff of a later moraine overriding the smoothed-ofT old moraine. The second or later moraine has here reached the Kara Kul sedi- ments overlying the first or older moraine and pushed up a distorted mass^of these Figs. 104 and 105. — Sediment pushed up by an overriding Moraine. sediments some 50 feet high (figs. 104 and 105). Great masses of the bedded clays lie tilted on others inclining in the opposite direction. Some stand on edge, most of them are bent, and numerous small columns stand where carved out by the wind, their stratifications showing inclinations either towards or from the over- riding moraine. These clays are at present ver\- brittle. Just to the east of this locality the coating of clays becomes thinner and in places seolian carving has exposed the underlying moraine, which, a little farther on, rises to view. On certain undisturbed surfaces of the sediments and in places on the beaches of both the old and the new moraines there are peculiar bushy concre- tions or growths of calcium sulphate mixed with clay (fig. 106). They stand upright, and are firmly cemented to the ground, which fairh- bristles with them over con- siderable areas. Similar concretions wen- seen forming in the brine pools on tlu- present lake shore. I am indebted to Pro- fessor Palache, of Harvard, for the analysis of these growths. From these various observations we may rea.sou : (i) that the older moraine predates the Kara Kul sediments at this point; (2) that tlie deposition of at least Fig. 106. — Concretionary growths of Calcium Sulphate on Moraine more than 1 00 feet above Lake. 142 EXPLORATIONS IN TURKESTAN. that thickness of sediments disturbed by the advancing later moraine predates that advance; (3) that the shore of a saline lake has retreated from about the 150-foot level to its present position since the maximum of the overriding moraine ; (4) that too little time has elapsed for much alteration either by solution or weathering of the salt growths since the lake-shore existed at that height ; (5) that it seems prob- able that the flexibility exhibited by the pushed-up sediments during the advance was due to their being well soaked under water. This might indicate that the lake was not only there after the overriding moraine had come to rest, but possibly also during the advance, and soaked the otherwise brittle sediments into a flexible state. We have seen that the Kara Kul sediments consist chiefly of the finest blue- gray clays, containing small flakes of mica and occasional small angular fragments of stone. The light blue-gray color is, in itself, remarkable, for all fine material brought down from the mountains to-day seems to be red. This shows that the old Kara Kul sediments are not oxidized, as are the deposits of to-day, and that Fig. 107. — Looking north from the front of the Kara Jilga Moraine to the Kizil Kul Steppe. the)- are in all probability a product of glacial grinding ; their thickness \-aries with the topography of the underljing old moraine. One minimum estimate gave a thickness of 40 feet where the wall, 30 feet high, of the elliptical lake described was seen through the clear water at least 10 feet below the surface. How much deeper the sediments continued could not be estimated. All this accumulation must have taken place since the maximum ad\-ance attained by the old underlying moraine. This, together with the width of the channel established b)' the Kok-sai dar)-a, is good indication of the antiquity of the underlying moraine. The kettle-hole topography of the overriding moraines, and the narrow V-shape of valleys cut in them, with the torrent condition of streams contained, show what a relatively short time has elapsed since they were formed. THE KARA JILGA MORAINE. It will be seen on the map that the Kara Jilga darja turns an acute angle at about 10 \ersts upstream from its mouth in Kara Kul, and now remains, partially filling the deep valley between this little lake and the angle of the Kara Jilga. Its surface is indented with frequent kettle-holes, and its topograph}- is, in general, very PHYSIOGRAPHIC OBSERVATIONS. 143 fresh. The moraine front forms an irregiilar, steep slope rising from the plain some distance below, and about a verst to the north of Kotir Kul. Starting at the base of the moraine, the plain inclines north to Kizil Kul (fig. 107). OBSERVATIONS IN THE REGION OF KIZIL KUL. Kizil Kul, as the upper portion of the Markan Su stream is indicated on the Russian io-\'erst map, is not really a lake, but simply a sluggish portion of the stream. Here the Markan Su heads in three branch streams, all of which run on broad plains of clear gravel, broken at frequent inter\'als on their borders b}- large fans of angular material. These plains join to fonn the more e.xpansive stepjie around the upper portion of Kizil Kul, and in the midst of this steppe a ledge mountain about 500 feet high rises sharply from the waste. From the midst of the various branch plains there rise numerous island tops of moraines, with apparenth' unaltered surfaces and slopes pitching sharply under the alluvium, while the valley sides themselves appear to be partially buried by the waste. There are, also, several ledge islands in the midst of the branch flood plain Fig. 108. — The valley heacling a little west of Kizil-Art and joining the Kizil Kul Steppe. coming down from just west of Kizil-Art pa.ss (fig. 108). Thus this whole region has the appearance of a deeply-carved valley system partialh- buried in waste, much of which must have accumulated since the dumping of the moraines, probably of the overriding class seen in the Kara Kul basin. There are also traces of low terraces contouring the slopes bordering the Kizil Kul depression, and remnants of an ancient plain to be seen sloping back in a gently rolling topography above the steep valley sides and on the ledge island some 400 feet above Kizil Kul. On a side excursion about 5 versts to the southeast of this point I came in view of a larger glacier a few versts to the east and flowing south from the Trans- Alai. Unfortunately there was not time to visit it, and the bad sand-storm that came up made it useless to take photographs. Through the field-glasses enough was seen of its long ice-flow to show that it that it might be an important point of attack for the glacial geolog}- of this region. FLUCTU.\TIONS OF L.\KK LEVEL .\ND GLACI.\L ADVANCES EXPLAINED BY CLIMATIC CHANGES. With the little time available it was hardly possible to make sufiicient obser\-a- tions to definitely pair off the glacial advances with the old shorelines of Kara Kul. It can, however, be stated that during each wet period the lake rose either till its 144 EXPLORATIONS IN TURKESTAN. surface increase gave enough evaporation to equalize the influx, or till it reached an overflow. Whether these wet periods were or were not coincident with the glacial advances remains to be pro\-ed. Since the annual range of temperature is here so low that it freezes nearh- every night even on the lowest steppes aljout Kara Kul, it is natural to feel that a sufficient increase of precipitation is all that is needed for a glacial advance, and that the glacial epochs of the past were brought about by the same wet periods which raised the surface of the lake. The only fallac}' here is tliat there might have been a wet period raising the lake level, but during which the annual temperature was so high that not enough snow would have accumulated to bring about a glacial advance. Perhaps the most extraordinarj- circumstance about Kara Kul is that it is said to overflow occasionally, although it is so strongly saline that long stretches of its shores are coated to a thickness of 2 to 3 feet with salt. Severtzoff" states that during high northerly stonns the water is driven up in the long southern arm, over- flows into a branch of the Murg-ab, and thence into the Amu dar^a. Fig. 109. — Drowned Valleys on ihe wesl side of the North Peninsula. Looking north to the Trans- Alai range. Unfortunately, we did not have time to visit the southern divide. It seems ver}" likely that it was blocked by moraine during the high expansions of the lake. A moraine during the earlier epoch might have dammed and raised the lake to the high levels marked by old worn-down terraces. During the long time intervening between the two advances it might have been cut down by overflow and other erosion and again raised by the overriding moraine of the later epoch. This reasoning would make the lake expansions coincident with the glacial advances. It is, however, complicated by the lowness of the northern divide over the Kara Jilga moraine, but Kotir Kul is, by Russian leveling, 600 feet above Kara Kul, and the divide at least 200 feet above that. Without the great overriding moraine this divide would be several hundred feet lower, so that Kara Kul may have had two outlets during the earlier glacial epoch, if it was during that epoch that the lake rose to the 200-foot or higher levels of the old terraces. There has, however, been no overflow over this northern divide since the falling into place of the overriding moraine, for its topography is unaltered. Tlie northeni peninsula rises abrupth' from deep water on the west, and more gradually from the shallow water and lake sediments on the east. Its western shore is indented with deep bays, from which rise steep spurs of rock as islands. The PHYSIOGRAPHIC OBSERVATIONS. 145 whole has tlie appearance of a mouutaiu iiiiiss formerly normally dissected above water and now flooded in the lower portions. These observations tend to show that when the normal dissection of the flooded part of the peninsula took place the lake stood far below where it is now, and possibly did not exist at all. It was then raised to tlie old high levels, and must have remained there a long time, for the shores, though now in many cases obliterated, are broad, even where cut in steep ledges. Then it fell again, and a relatively long time afterwards was raised to about the 150-foot lev^el, where it remained some time and then graduall)' receded, leaving its fresh shores following in and out of the old peninsula valleys. The lake surface appears to have stood at its present height for but a relatively short time, for its shores show very little cutting from wave action (fig. no). Considering all facts about the Kara Kul basin, we see that, although there is no absolute proof for associating the old shorelines of the lake with the glacial advances, they naturally group themselves together by probability' ; for if Kara Kul exists as a result of moraine damming and if, as seems more than likely, ice epochs occurred during times of increased precipitation, the greater fluctuations of lake level were doubly controlled by glacial epochs. Moreover, the ancient 300 to 400-foot shorelines are in their imperfect state of preservation similar in antiquity to the old deeply clay-buried moraines, and the shorelines marked from about the 150-foot level down are similar in their freshness to the overriding moraines with their unaltered surface topography. As further evidence we have the fact that the overriding moraines are cut, where they extended suflliciently low down, by the 150-foot and lower shores, but not cut by the 200 to 320 foot and higher levels. It therefore seems proper to state that the lake surface appears to have risen to a height of 320 feet or more during the first glacial epoch established and to a height of about 150 feet during the second glacial epoch established. GLACIAL EPOCHS. It seems only reasonable to suppose that epochs of increased glacial conditions were coincident on both sides of the Trans Alai range and in neighboring regions. In the Great Alai Valley and on the Pamir we have one class of moraines of similar antiquity and extent, another of similar freshness and e.xtent, and indications of a third still later class of little extent. Evidence thus places each class on the Pamir as contemporary with its respective similar class in the Great Alai Valley. To distinguish the two definitely established glacial epochs we may name the older one the Alai Epoch and the later one the Kunundi Epoch. It is therefore at present convenient to divide Quaternary- time for the field in which I worked into five parts — f Post Kurumdi. I Kurumdi Epoch. Quaternary \ Orogenic Epoch. I Alai Epoch. I Pre-Alai. 146 EXPLORATIONS IN TURKESTAN. FORM OF THE GREAT ALAI VALLEY, THE VALLEY ITSELF. Although the dimensions of the Alai Valley have already been given, a repeti- tion seems necessary. It is, except for the flood plains of streams, a smooth, grass- covered plain about 75 miles long, averaging 12 miles in width, and broken by transverse undulations where moraines project from the principal side valleys. It has a longitudinal pitch from 10,500 feet at the pass on the east to 3,200 feet at Darak Kurgan on the west end, and a transverse inclination of about one-half a degree alongside streams from its southern to its northern border. The Kizil Su, or trunk stream, thus flows close to the northern border. Very few of the side streams coming down from the Trans-Alai, or southern border, reach the Kizil Su, except in high flood. On July 14 we followed the flood plain of the Kizil-Art dar>-a, which is one of the larger streams, from Bor Daba to the Kizil Su. Although there had been three days of rainy weather, all the channels of this stream were dry at 15 versts down from Bor Daba. The lower portions of the flood plains of larger streams from the Trans-Alai are often several versts in width and generally of clean gravel, with certain strips grown over with loess, and rising in the middle to a considerable height above the surrounding plain. These observa- tions, together with the extensive distributary s)-stems as seen on the map, are good evidence of delta accumulation. In the eastern half of the valley the Kizil Su itself is a sluggish stream and incapable of transporting more than a very small propor- tion of the immense amount of waste supplied by the Alai Valley tributaries. This is shown l:)y the splitting of the stream over long stretches and absence of any permanent channel cut down below the surrounding plain. We have seen that, in the past, great accumulations of moraine were brought into the Alai Valley, that since the Kurumdi, or later glacial epoch, great depths of moraine of that advance have been l:)uried by later waste, and that the valley is now rapidly filling up with alluvium. A general glance at the valley as a whole would show that it has the character of a fonnerly deep \'alle)' now much filled up with waste. The ledges flanking the mountains on both sides of the valley slope sharply into alluvial and glacial deposits. It wotdd be interesting to know how long this valley has been filling up, what proportion, if any, of this filling took place before the Alai glacial epoch, what proixyrtion between the Alai and Kurumdi epochs, how much since the Kurumdi epoch, and how far down it would be to bedrock in a cross-section. Much light might be thrown on these questions in exposures of the gorge at the outlet to the valley. It seems highly probable that the valley has suffered from morainal blocking. This might explain the existence of the gorge that drains it as a drop-over from the high zone of morainal blocking and consequent alluvial accumulations into lower regions unaffected by glacial action. SIDE TRIBUTARIES. The side valleys emptying into the Alai Valley from the Trans-Alai range have already been described in paragraphs on glacial geology. It was shown that there had been a lowering of baselevel of those streams from the south and consequent cutting PHYSIOGRAPHIC OBSERVATIONS. I47 down of tlieir floors since the close of the Alai glacial epoch, and that, although most of this cutting down took place before the close of the Kunnndi glacial epoch, the upper portion of at least the Kizil-Art darya is still cutting down in rock bottom. The valley fonns of those side streams coming down from the north, from the Alai range, might well be called a reverse of those from the south or opposite side of the Alai \'alle\-. We had a good general view of manj- northern tributaries from a distance, and made a detailed study of the Sari Tash \'alley, which heads at Katin-Art pass. This belongs to that class of valleys which had in the past the steep V-shape, containing torrent streams, but which have since been largely buried by waste, forming a broad, flat surface over which their now sluggish streams meander. In the Sari Tash Valle}' only peaks of the rock core rise from the nearly talus-buried mountain sides (figs, no, in). There is practically no transportation; the talus is stationarj' and coated nearly to the top with loess and grass. The stream meanders (^=talus; i5=liraestone ; a^=anuvium.) Fig. 1 10. — Section looking north up the Sari Tash Valley. between grass banks to within half a mile of the coast, where it winds between interlocking fans of talus. A few versts east of the mouth of this valley there rises an island spur separated from the rest of the range by Alai Valley alluvium. EXPLANATION OF CONDITIONS. It is evident that the whole side-valley system of the northern border has been deeply submerged in alluvium, whereas the system opposite, on the southern border, has been cut down. These reverse conditions might be explained by a simj)le tilt of the region decreasing the grade of southerl)- flowing streams and increasing that of northerly flowing streams ; but, as will be shown later, that would not fit in witli what has happened to the Alai Mountains. The simplest explanation seems to be a sinking of the Alai Valley with the region including its northern tributaries. If this took place with a fault on the southeni border, it ought to have left a fault cliff" which might explain tlie escarpment at the base of the Trans-Alai range, which escarpment has been described under observations on glacial geolog}-. Suess states on authority of Ivanof that the Alai \'alley is partiall\- surrounded by lake terraces. He considers this valley as orogenicallj- the eastern extension of the Zerafshan and drains the supposed lake through a gorge cut back bj- a capturing 148 EXPLORATIONS IN TURKESTAN. branch of the Amu dan-a, which is the present outlet of the Kizil Su. It seems highly probable that the Alai \'alley, with its great transverse moraines, may have held one, or even several, lakes dnrino^ glacial ejxjchs ; but a lake reaching to the height of our escariDUient terraces would be high above the lower passes over the Alai range, and, moreover, we observed no lake sediments. Fig. 1 1 1. — The eastern side of^lhe Sari Tash^Valley from about 5 versts]^below Katin-Art_Pass. It seems probable that a sinking of the Alai \'alley with the region including the northern side tributaries, accompanied by a fault on the southern border, would have resulted in the obser\-ed truncation, lowered the base of, and caused the deepening of, the Trans-Alai side valleys, while the part going down would have been filled up with waste. This fits the present conditions observed. Fig. I 12. — Remnants of Floor A, as seen looking down from jusi below Taldic Pass. OBSERVATIONS IN THE T.\LDIC VALLEY. Our route led us twice along that part of the Taldic dar}-a between its somce at Taldic pass and Gulcha on the southern border of the Fergana lowlands. On the waj- up a general idea of the valley fonn was obtained ; on the way down more detailed observations were made. * It will be seen on the map that this stream starts with a northeasterh- course, but gradually bends toward the west, and finally recrosses the meridian of its source. A straight line from Taldic pass to Gulcha points but a few degrees east of north. PHYSIOGRAPHIC OP.SERVATIONS. 149 The Taldic Valley increases in depth from about 500 feet near the source to about 3,000 feet just above Gulcha ; a little below Gulcha it emerges into a relatively shallow channel on the lowland plain, and finally joins the Kara dar\'a, a branch of the Syr. It varies greatlj' in width, according to the hardness of the rock. For about 15 versts, part in black silicious limestone, part in granite and hard slate, it Fig. ! 13. — Taldic Valley Terraces, looking up the Taldic Valley from Floor B, about 63 versls above Gulcha. Floor A is high up on the right. narrows to a deep canyon, where the stream is a roaring torrent running partly on ledge bottom. Where cut in the gypsum series it broadens out, with sides sloping back in successive steps over extensive terraces. Except where in the above-men- tioned canyon, the Taldic darya, from about 20 versts below its source to Gulcha, is directly contained in a channel of often rectangiilar cro.ss-section, averaging some- Fig. 1 14. — Taldic Valley Terraces, looking up the Taldic Valley from Floor C, about 46 versls above Gulcha, thing like 500 feet in width and 100 feet in depth, and cut in partially cemented alluvial conglomerate. When in high flood the stream covers the whole breadth of the bottom ; at other times it is largely split into smaller streams rejoining each other on its irregular gra\el flood-plain. The accompanjing profile of the stream has been constructed with the aid of Russian leveling notes, and tlie characteristic terraces have been projected onto it from my approximate measurements. These terraces have been lettered A, B, C (figs. 112-114). I50 EXPLORATIONS IN TURKESTAN. The first traces of floor A are found as long sloping spurs, projecting trans- versely into the valley below Taldic pass. Extending down the \alley, it rapidly broadens out on alluvium-covered terraces, and appears to ha\e emerged on to a waste- covered piedmont plain, reach- ing to witliin 25 versts north of the present Alai range axis. This plain has now been exten- sively dissected, and remains only in frequent flat-topped hills capped with horizontally hing conglomerate and in the sharper tops of other hills and spurs reaching to the proper height. It will be seen by the profile that it spreads horizontally to the north from the range axis and remains in terraces and al- luvium 3,500 feet above stream at Gulcha. There were higher hills that rose as residuals from the alluvium covering portions of the level of floor A (fig. 112). Reaching a point about 3 versts down the valle>- from Taldic pass, the stream emerges abruptly from its torrent gorge into the wide valley at Ak-Busa- Ga. The accompanying sketch map (fig. 115) gives a rough idea of the dimensions of the plain of the valley floor and posi- tions of the main stream and tributarj' channels at Ak-Busa- Ga. Here we find a transitional state. The trunk stream has sunk a channel 15 feet deep through the grass plain and into alluvial conglomerates, while the side tributaries pass over falls into their gullies leading to it. Since these falls are some dis- Fig. 1 15. — Map of the Ak-Busa-Ga grass plain and stream channels. tance from the plain border, it is evident that these streaiTis ha\-e not had time to cut back into their respective vallej's since the trunk channel was sunk. Passing down through Ak-Busa-Ga outlet, we find that the grass plain is there higher above EXPLORATIONS IN TURKESTAN, Elevation in feet 15000 PROFILE OF VALLEY TERRACES AND MORAINES FROM OSH TO KARA KUL PHYSIOGRAPHIC OBSERVATIONS. I5I the stream and forms the beginning of the floor B terraces. These are, at first, narrow, sloping terraces on parallel bedded alluvial conglomerate, but broaden as they are followed down the valley, at the same time increasing in height above the stream at the rate of about 26 feet per verst, and at Gulcha are about 2,000 feet above. Floor B has, however, been much dissected, the tributaries having cut down on a normal grade to the trunk stream, leaving intervening alluvium-capped hills and spurs as portions of the old rock bottom. Its greatest width, of many versts in the lower half of the valley, is evidence of prolonged action and meandering of the stream to an extent well towards maturity at the B stage. Floor C seems to be the last great characteristic in the records of this valley. It coincides with floor B on the plain of Ak-Busa-Ga, but, having a steeper grade, separates from it a verst or so farther down the valley, soon attains its full height above stream, and continues practically parallel with it all the way to Gulcha, except for a few short stretches missing in the canyons. This floor is remarkably fresh in every respect, and sunnounts the present bed of the stream over a large proportion of its course with vertical and often with overhanging walls. The larger branch streams have alread}' cut down to the tnink stream on a normal grade, but small tributaries still fall from floor C in hanging valleys. Long portions of the valley sides between A and B, and between B and C, are marked with transitional terraces, and where the valley widens there is a series of three, and sometimes more, freshly cut terraces stepping down from floor C to the present stream bed. The striking divergence of terraces is seen b}- a glance at the profile. The nmning out of the A and B terraces is a characteristic feature soon recognized in the valley, and it was from that fact that the block tilt described below was first inferred. OBSERVATIONS ON THE SOUTHERN BORDER OF THE FERGANA LOWLAND PLAINS. About 30 versts down stream from Gulcha the Taldic darya emerges on to the lowland plains of Fergana. We made a brief study of the southern border of these plains from 20 or 30 versts east of Osh to Jisak, on the railroad, 30 versts northeast of Samarkand. Most of this stud)- was from the railroad train, but there was more detailed work done in the region of Osh, and obser\'ations made there ])rojected on to the similar forms along the rest of the border. It was found that the waste from the Alai Mountains, formerly spread in extensive fans on the border of the plains, has been tilted up towards the mountains, dissected in its upper portions, and buried bj- later waste on its lower portions. It was obsei"ved from a distance that, in general, the Alai range foot-hills begin in long flat-topped masses parallel with the range and rising abruptly to a considerable height above the plains. The stream followed by the route from Langar to Osh crosses tlie critical zone, including the dissected waste and the line where it inclines under the later waste. The upper part, or that followed between Takka pass and Langar, was found to have cut back a narrow channel increasing in depth to about 60 feet at Langar, 15^ EXPLORATIONS IN TURKESTAN. where a Russian station-house stands on the terrace sunnounting it. The side rivulets pass, on their way to the tnmk stream, through deep gullies with a sharp double change of slope in their cross-sections, as though there had been an increased rate of cutting down (fig. ii6). They are cut in partially cemented conglomerate, inter- bedded with fine material. The station-house ter- race extends down the valley parallel with higher terraces, all of which are cut in apparently hori- zontally bedded conglomerate. As this conglomerate was followed down the valley, it was found that a larger and larger pro- portion of it assumed the fonns of partings of -Section to show double change of g^avel, filled between with fine pulverous material slope in Langar Gullies. resembling locss. Througliout the lower portion of the valley the stream resembles the Taldic darva in that it is largely split into sepa- rate channels rejoining each other on the irregular flood plain of gravel. There were occasional higher island portions between these channels, which were coated with loess, sometimes pure with \-ertical cleavage, sometimes interbedded with part- ings of gravel, and grown over with grass. About 20 versts from Langar the valley opens out on to the lowland plains. On the way to this point, the terraces seen in the upper portion of the valley had successively disappeared under the flood plain, while here tlie conglomerates formed Fig. 1 16.- Fig. 1 17. — Section en route, 20 versts north of Langar. looking 15' south of west. the later waste. The tilted waste inclines under a low, broad .slope inclining gently to the north and sinking under the loess of the lowland plains along a well-defined line, running about 15° south of west. The slope itself was cut by shallow valleys pitching directly with its inclination, running par- allel with each other, and with their lower portions apparently submerged in the waste they had spread on the plains. Looking south toward the mountains, we could see that the conglomerate slope extended back on to the flat, inclining surfaces surmounting pyramidal masses dissected from it, and still farther back, over the sharp tops of higher hills (fig. 117). PHYSIOGRAPHIC OBSERVATIONS. I53 ATTEMPT AT ^CORRELATION OF RECENT GEOLOGY OF THE MOUNTAINS AND PLAINS. The following suppositions seem to account for the various land forms observed along the route from Kizil-Art pass north to the lowland plains, but it should be added that generalizations, such as block movements, can not be definitely established without a study of se\'eral other profiles across the ranges in question. (i) Floor A of the Taldic Valley profile, the great extent of which was seen from prominent points above the valley, is evidence that in earlier Quateniar)- time the Alai Mountains had been degraded till a waste-covered piedmont plain had formed on the north side to within 25 versts of the core of the range. (2) When this stage had been reached, there seems to have taken place a dis- location, essentially parallel to the range axis, and some 75 versts to the north of it, while either the plains to the north sank or the mountains were raised by a block uplift. Whichever happened, it appears that the mountains with a belt some 50 versts in width of the old piedmont to the north were raised at least 1,500 feet relati\'ely to the plains north. As this movement took place, the Taldic dar^-a, as an example, cut down through the raised piedmont and formed a valley increas- ing in depth from about 500 feet near the crest to 1,500 feet at the dislocation, while its various tributaries dissected the mass on both sides, leaving portions of the old plain, some of which still exist as floor A, recording its former extent. The floor of the trunk valley thus formed is the one lettered B in the profile. (3) The great width of floor B in the lower half of the Taldic Valley, and the considerable thickness of alluvium on its old ledge bottom there, are evidences of prolonged meandering of the stream and filling back of waste. In other words, there was a decrease, or possibly a cessation, of relative uplift at the B stage. (4) There seems, then, to have begun a block tilt of the belt hing between the northern base of the Trans- Alai range and the old dislocation zone, about 75 versts to the north of the Alai range axis, the rotation taking place about a line some- where under the present Alai range axis, raising that part to the north and lowering that to the south. As a result, those streams flowing north in the Alai Mountains cut their way down through that part which was raised, lea\ing mnnerous terraces to record the transition. At the same time, the head of the Taldic valley, being south of the rotation axis, was tilted back, decreasing its grade, which explains the preservation of floor B in the broad grass-plain of Ak-Busa-Ga. The lower portions of valle)- s\stems south of the crest were being tilted down below their Alai \'alley base-level, and consequently choked with waste. Another consequence of this tilting down, suggested by Professor na\is, was the increase of grade of slope from south of of the Alai crest, aiding the transportation of loose material and a rapid sharpening of the peaks which to-day project as pinnacles from the talus slopes (fig. 119). A block tilt seems to be the only way to explain the rapid increase of height abo\-e stream of terraces in valleys ninning north and the deeply filled up character of valley systems running south from the supposed rotation axis. ]\Ioreo\er, the old piedmont, or floor A, now lies horizontal, although it must have fonnerly inclined to the north. 154 EXPLORATIONS IN TURKESTAN, How much width of the Great Alai Valle\- was incUided in the block tilt is uncertain. It was, however, shown in the discussion on the Alai Valley fonn that there has been a lowering of base-level and consequent deepening of the valleys emptying into the great valley from the Trans- Alai range, and that this lowering had taken place since the close of the Alai glacial epoch. It was further shown that this took place with a depression of a belt including the side-valley systems from the north and possibly reaching to the ver>' base of the Trans-Alai range. The depression and filling up of the Sari Tash Valley and others running south from the Alai range was probabh- brought about by a block-tilt. This tilt can explain the observed changes of both the Alai and Trans-Alai ranges, and since the deepening of valleys in "-^ the latter took place after the close of the Alai glacial epoch, this tilt probably occurred since that epoch. It is, however, not likely that this one tilt was the only move- ment that took place ; in fact, we have seen that the border of the lowland plains was tilted up, presumably during the block-tilt, and there is no reason to suppose that the Trans-Alai range did not, at the same time, move either up or down a little on the block-tilt dislocation bordering it. If the tilting of the waste on the lowland plains was caused by a drag-up on the block-tilt dislocation there, the tilted waste was deposited largel>- during and before the Alai epoch, while the deposit overlying its lower portions are, in age, from bottom up, orogenic to present, inclusive. The relative antiquity of different horizons might be estimated in two ways: (i) as directlv proportional to magnitude of dip less normal surface slope of fans of that coarseness of material ; (2) as directly proportional to thickness of overlying accumulations. These methods would, however, be complicated from the fact that the rate of tilting seems to have been accelerated from the beginning, for the transition of valley form was always to the narrow from the broad. This compli- cation might be overcome by careful measurements of terraces and determination of the factor of acceleration. EX.\MPLE. Fig. 118. — Explanatory diagram for example in determining relative antiquity of horizons of the waste on the plains. Let n be the present surface with normal slope. the ages of which are to be detennined. (See fig. 1 1 Let dA and dB = depths below surface. age ^ <{A- Let A and B be two horizons, S.) Let / = acceleration of tilting. estimate. ageB n) l_ <{B-n)^ f dA I —7- X -, as a rough PHYSIOGRAPHIC OBSERVATIONS. 155 MISCELLANEOUS OBSERVATIONS ON THE LOWLAND PLAINS. In the region of Osh there are several high, nigged mountains of cn'stalline limestone rising as monadnocks from the waste of the plain. The Syr Dar)-a, where crossed between Khokan and Schust, was found to flow but a few feet below the level of the plains. The ruins of the ancient town of Ak-si are being cut by the river meandering, but no definite data as to change of level or relations was obtained. The waste of the plains on the northern border has been tilted up toward the mountains, dissected in its upper portions, and buried in its lower portions, in a manner similar to the southern border. Fig. 1 19. — TTie sharp peaks south ot the Alai Crest. Taken from a peak some versls east of Kalin-Art Pass. CONCLUSION. The results of the Pamir expedition have shown that the correlation of the recent geolog}' of the mountains and the plains in the field we covered is not only possible, but practicable, to attempt. We have already found a general connection between magnitude of the valley canning brought about by orogenic movements and distribution of corresponding depositions on the plains, and have, to a certain extent, found the glacial division of time in which these movements took place. When we consider the few^ days in which all this was found out, it seems that more detailed work on the terraces and dislocating zones ought to jueld remarkably anah^tic results. If work is to be continued in this field, the following plan is suggested : 1. A detailed study of Sok Darja Vallc}', which heads in the two large glaciers in the heart of the Alai range and flows north on to the lowland plains of Fergana. 2. Having found the relations of terraces to moraines and to the border of the plains in the Sok Dar^-a Valle}', proceed to study the great longitudinal valley of the Zerafshan, where artifacts are extreme!)' abundant. Then, if definite relations of artifacts to alluvium, to terraces, to moraines, are found, time units may be projected to erosion, and deposition units determined in the first valley. 3. It would be of great interest to correlate the old expansion of Great Kara Kul with the glacial advances, and to make volinnetric and surface area determinations of each expansion and its sediments. A few approximate profiles would do this. 4. A careful study of the Great Alai \'alle)-, and an attempt to detennine the thickness and age of its glacial debris and of the waste filling it. The entrance of the gorge at its outlet might be a good point of attack. TURKESTAN MAP OF SOUTHEKN TURKESTAN . Riiuu- of wlioK- j.a _huiij.<-llv i-i.ilv _ tllllltlllf^lUll |JIUlV ao BO loo r\ A Geologic and Physiographic Reconnaissance in Central Turkestan. By Ellsworth Huntington, Carnegie Research Assistant. 157 A Geologic and Physiographic Reconnaissance in Central Turkestan. Bv Ellsworth Huntington, Carnegie Research Assistant. ITINERARY. The following pages present the results of a journey in Central Asia, among the mountains of Russian and Chinese Turkestan, during August and September, 1903, under the auspices of the Camegie Institution of Washington. The i)uq)ose of tlie journey was specifically the detennination of the later geological history of the region, and especialh- of the changes in the physical conditions of the country with respect to their influence on early lunnau history. In the absence of any gen- eral knowledge of the physiography of the region it seemed advisable to undertake a reconnaissance in which the more obvious problems were examined, while those that required prolonged work in one place were deliberatelv set aside for future study. In pursuance of this plan, two months were spent in following the route shown on the accompanying sketch map (fig. 120), traveling slowl)- on horseback at the rate of scarceh- 25 miles a day, and rareh- staging in one locality over two nights. From the town of Przhevalsk, fonnerly known as Kara Kul, at the eastern end of Issik Kul or Lake Issik, the road led (July 27) southwestward over the lofty Tian Shan plateau to Chadir Kul (August 6), thence southward, still among the mountains, to Shor Kul (August 15), and again southwestward across the border of the interior basin to Kashgar, the capital of Chinese Turkestan (August 21). The return journey led westward across the mountain spur between the Tian Shan and Alai ranges, via the Terek pass, 12,700 feet high, to Osli, in the Fergana basin of Russian Turkestan (September 5) ; then southwestward to Karategin in tlie Alai Mountains (September 18) ; and finally northward again, to Marghilan and the railroad (September 25). Although ten passes were crossed at a height of over 12,000 feet, the road on the whole was not one of great difl[icult\-, and troublesome snow or ice was encountered in only three places. The district traversed measured about 350 miles from east to west, and 225 from north to south. 159 i6o EXPLORATIONS IN TURKESTAN. PLAN OF REPORT. Although the main purpose of the reconnai.ssance was the study of the ph%siograph\- and Ouateinar\- geologA' of the countn-, some attention was given to the records of earlier times. .Accordingly, it is proposed to discuss first the Paleo- zoic geology ver>- briefl\ , llitn the Mesozoic and Tertiary geology more at length and with some mention of their relation to formations of similar dates in south- western United States, and lastly the Quaternary geology, which will be taken up with considerable fidlness. Under the last head will be included a discussion of the physiographic jiroNinces into which the region is naturally divided and of the processes which have been instrumental in producing the present land forms. In conclusion, some attention will be devoted to a consideration of the evidence of changes of climate during recent geological times and to an attempt to subdivide the Quaternary era on the basis of these changes. 20 40 DO 80 100 Authors route Fig. 120. — Sketch map of Central Turkestan. THE PALEOZOIC SERIES. In Central Turkestan a single succession of strata is repeated again and again, with only slight local modifications. The oldest obser\-ed fonnation is an ancient white marble, shot through and through with intrusions of granite. It was noticed only in the Alai Mountains in the neighborhood of Kok Su and Karategin. Its junction with the overlving formation was not seen, but the contact presumably shows an unconfonnity, as a conglomerate near the base of the covering strata contains pebbles of the marble. The granite which is intruded into the marble is of much later date, for it occurs abundanth' in the Paleozoic series in the ridges of the Tian Shan plateau and along the north side of the Alai range. The main body of the Paleozoic series is a great thickness of limestones, many of them .slaty, which are stated by Tchernachef to be of Devonian and Carboniferous age. They are greatly folded and have been penetrated not only by granite intrusions, but also by RECONNAISSANCE IN CENTRAL TURKESTAN. l6l some basaltic lavas, as may be seen, for instance, in the Sugun Valley west of Shor Kul. The folding of the Paleozoic strata (see fig. 122) is of the sort which is associated with mountain building, hence at the end of the Paleozoic era or in the earh- part of the Mesozoic this part of Central Asia must have been highly mountainous. In evidence of this it may be pointed out that the succeeding unconfonnable conglomerates are so coarse that they could only have been fonned Fig. 1 2 1 . — Sketch map, showing location of Figure 1 20. subaerially in a region of considerable relief, and yet at the time of their deposition the old folds of limestone and slate had already suffered great denudation. As a rule, the hard Paleozoic strata are found in the highlands, while the softer Mesozoic and Tertiar\' strata occur in basins among the highlands and mountains ; but this seems due less to the superior resistance of the older rocks than to the fact that thev were bent down where they are covered, and that the younger strata were largely fonned in the very basins which they now occup)-. l62 EXPLORATIONS IN TURKESTAN. II o.s to H n •< H JS_- mo: Q Q Q Q -= I -i J s a S fS i K J a: Q Q Q Q g>- ■^ -5: N i- Is « o *2 1.j -= o S a « o £0 H U - E^ m D Q Q O Q Q Q Q Q Q 31 -zJS S Q Q Q a U" - u 02 • C £ o _2 c .11 i a ■J s •a I ■s a 4 « S ■5 g S > u I 4U — o e — w E — O c O^ 2 O («^ ' uniform over large areas. The overlying Tertiary layers consist of red sandstone, which often forms a bright carmine band one or two hundred feet thick, a heav\- pink sandstone, a brown .sandstone, and a thick brown conglomerate. These strata form a single series, and pass gradually into one another witli no unconfonnities, e.xcept a slight one between the pink and the brown sandstones which was noticed in the fine section near Sunguu, west of Shor Kul. The term "sandstones," as applied to all these formations — the red (carmine), the 164 EXPLORATIONS IN TURKESTAN. pink, and the brown — is not exact, for while certain parts are composed of true sand, small portions are shaly, and large parts are composed of very fine material, which is neither sand nor clay, bnt a sort of silt which often reseml)les loess. Tlie bedding is very even at the hone, but signs of subaerial deposition make their appearance below the middle of the pink beds. At first there are sun-cracks and ripple-marks, then thin lenses of a slighly different texture from the surrounding rock, and finally in the brown sandstone veiy distinct stream channels filled with fine gravel. Throughout the Tertiary series, from the limestones upward, the layers are discon- tinuous; at any given point the bedding seems horizontal and unbroken, yet if individual beds are traced for some distance they gradually die out. Fig. 123. — Ripple-marks on the lower half o( the pink sandstone near Kan Su, west of ICashgar. The conditions under which the Mesozoic-Tertiary series were deposited seem to have been largely subaerial, or at least non-marine. The coarse conglomerates at the base probably indicate arid or semi-arid conditions in a region of considerable relief. As relief grew less, or as the climate grew moister, the gravel of the con- glomerate gave place to sand and that in turn to shale ; in the latter are four or five coal seams. The next period, that of the vennilion beds, seems to have opened at a time of subaerial deposition when the conglomerates and the cross-bedded .sand- stones were fonned; but toward the end the encroachment of the sea is indicated by the deposition of the marls and fossiliferous limestones. Elsewhere throughout the whole Mesozoic-Tertiary series fossils seem to be wholly absent, although the deposits are well fitted to preserve the remains of plants and animals if any had RECONNAISSANCE IN CENTRAL TURKESTAN. 165 existed ; but here the calcareous strata, which show other evidences of being marine, contain fossils in abundance. Above the limestones the strata are at first red, as though the shallowing of the sea allowed the ver}' highly weathered soil of an old land mass to be washed farther and farther out into the area of deposition. The succeeding formations, the pink and brown sandstone and the brown conglomerate, show a nearer and nearer approach to present conditions. It appears as though, after the retirement of the sea, the land was covered with great playas, on which water first stood in thin sheets, fonning ripple-marks in the mud (see fig. 1 23), and then retired or was evaporated, allowing the surface to become sun-cracked. As time went on streams began to flow across the plajas, at first slow and broad and able to cut only shallow channels, which were afterwards filled and covered, assuming the form of very thin lenses of a material slightly different from that of the surrounding playa strata. Then, as the strength of the streams increased, sand was deposited over the whole area, and the channels, now deep and distinct, were filled with gravel. Lastly, gravel was deposited almost everywhere. Some of these changes may be of climatic origin, some may be due to warping of the crust, and some seem to result from the lessening of relief by erosion. Thus in the earlier Mesozoic times the change from coarse conglomerate to the fine coal shales may be due entirely to the last-named cause, by which, as the mountains were worn away and the intennount basins were filled, relief became less and the size of the transported materials became smaller, until the coal-bearing shales were formed. The ne.xt change, from the coal measures to the red conglomerate and the cros;;- bedded .sandstone, is much more sudden and probably indicates a warping and uplift by which previously base-leveled areas were raised and subjected to active erosion. The redness of the strata and the predominance of small pebbles of pure quartz in the gravel indicate that the materials were derived from a region that had long been subject to undisturbed weathering. It is possible, too, that the uplift was of such a nature as to cut off the supply of moisture which had been present during the formation of the coal and to convert the country into a desert, where the wind produced large-scale cross-bedding of the red sandstone. There is no positive evi- dence on the subject, and we can merely raise the question of the desert origin of this peculiar deposit. From the time of the cross-bedded sandstone to that of the limestones of the Cretaceous there appears to have been a steady sinking of the land or rising of the sea until at last the whole country was inundated. Through the succeeding period to the Tertiary there is no sign of climatic change. Everything points to a steady warping and lifting, by which relief was gradually increased in such a manner as to cause the deposits to change from marine to subaerial, and then gradually to change in texture from the fine silt of playas to coarse conglomerate. The warping seems to have been greatest along the borders of the present basins, for there we find the strata of the whole series considerably folded, while in the centers of the basins they are almost undisturbed. The older strata, too, seem to be more bent than the younger, so that the process seems to have gone on steadily almost from the beginning of deposition. 1 66 EXPLORATIONS IN TURKESTAN. f» COMPARISON WITH AMERICAN FORMATIONS. Before leaving the Mesozoic-Tertiary series there is another phase of the subject which deserves mention, because of its bearing on the world-relations of the con- tinents. The existing physiograjihic features of this portion of Asia bear, as has been suggested, a certain resemblance to those of the southwestern jjorlion of the United States, the so-called Rasin Range and Plateau provinces. If the rock series and the geological events of the one country be compared with those of the other it is .seen that while there is considerable difference in details, there is also a significant resemblance ; hence the fundamental features of the past, as well as of the present, are similar. This is set forth in Table II, where American features which are the same as those of Asia are marked " Do." It is not meant to imply that the two series of features were identical in time, but merely in sequence. The similarity seems too great to be accidental ; it may l)e that we have here the normal sequence for an interior desert basin. If this is so we ought to find the same general rock series in other desert regions, such as Arabia and parts of the Sahara, where similar conditions prevail. Table II. — Comparison table of the Mesozoic-Tertiary rock series and of geological events in the elevated arid regions of Asia and North America. Asia. North America. Roclu. Events. Rocks. Events. 6 7 8 9 10 11 12 Limestone and shale. . ....Do Do. Mountain- making and prolonged erosion. Shales Estuarine or playa deposition. Conglomerale and sandstone. Subaerialdeposition. Land slowly sinking or stationary. . . Do Do. Slight unconformity. Clay shales and coal measures. Estuarine or swamp conditions . . Blue mails Elstuaiine conditions. Vermilion sandslone, cross- bedded. Elevation and possibly desert conditions. ... Do Do. Limestone and gyp- sum. Depression and return to moraine conditions. White cross-bedded sandstone. More rigorous desert conditions. Marl and limestone- ■ Unstable marine conditions Cretaceous coal meas- ures. Estuarine or swamp conditions. Oyster limestone ....Do Do. Red and pink beds ■ ■ . EUevation and eventually a gradual return to subaerial conditions ot depositions Do Do. (Pink beds.) Brown sandstone and conglomerate. Complete return to subaerial deposition. Do Do. RECONNAISSANCE IN CENTRAL TURKESTAN. 167 THE TERTIARY PENEPLAIN. The unity of Central Turkestan is shown not only in the wide extent of the various members of the rock series, but also in the extensive peneplain which truncates them. In all parts of the region there are numerous places where the surface of interstream areas presents a smooth, gentle slope quite out of hannony with the tilted strata which it truncates evenly without regard to whether they are hard or soft, and with the steep-sided \'alle)-s that are being cut in it. These areas are therefore regarded as uplifted and more or less dissected parts of a fonnerly low-lying j^eneplain of erosion. In the southern part of the Tian Shan plateau, for example, the large plateau basin containing Chadir Kul and the Ak Sai River and lying at a height of from 10,000 to 1 1,000 feet above the sea is bounded on the south by a broad ridge or swell rising to a height of from 13,000 to 14,000 feet. On the southern slope of the ridge there is a descent of 9,000 feet to the plain of the Kashgar basin in a distance of from 70 to 15 miles — that is, a descent of from 120 to 600 feet per mile. This descent is sufficient to cause active erosion, which in due time will produce the most irregular topography with a ma.xinuun of relief; but the valleys of the south slope are not }et profound and the interstream areas, though very rugged, rise everywhere to the height of a nearly smooth imaginaiv' surface ascending from the Kashgar basin to the broad ridge which incloses it on the north. This surface is evident in the hard Paleozoic formations and can be detected even in the soft Tertiaries. A broad ridge with such a slope descending from it must soon become very rugged by reason of the headward erosion of the streams ; but here, especially in the eastern portion, the southern ridge of Tian Shan is still quite smooth and level, and its surface is indifferent to rock structure ; hence its elevation from the condition of a low-lying peneplain must be com- paratively recent. A smooth plain (plateau) of large extent stretches northward from the ridge, sloping at an average rate of about 100 feet per mile toward the Ak Sai basin and tnmcating the almost vertical slates and limestones of Paleozoic age (see fig. 124, p. 172, southern end). Not far to the west, in the district southeast of Chadir Kul, there are a number of eas)- passes across the same ridge, which there forms the Chinese boundar)-. Two of these passes, Kara Kennak and Kuzzil Kur, are in the soft upper members of the Tertiary series, although at an ele\ation of over 12,000 feet. It is evident that the smooth imaginary' surface to which the tops of the hills rise on the southern slope of the Tian Shan, above described, and its more actual continuation in the plateau, which tnmcates the Paleozoic .strata farther north, could not have been fonned by an)^ known process under the present conditions of altitude and drainage ; nor could the weak Tertian,- strata of the passes farther west have been long preserved in their present fonn at the elevation at which they now lie. In order to reduce the deformed strata to .so smooth a surface the Tian Shan region must have stood many thousand feet lower than now, until it reached a late mature or oldish stage of erosion, deser\'ing to be called a peneplain, over large areas. The present altitude of the region nuist be due to uplift and warping of the peneplain l68 EXPLORATIONS IN TURKESTAN. and its residual mouulaiiis, and in order that the weak Tertiary strata should still exist in the warped and uplifted plains, its deformation nuist have been compara- tively recent. Numerous other examples of this kind might be cited, but one will suffice. At Giilcha, about 30 miles southeast of Osli, on the border between the Fergana basin on the north and the Alai Mountains on the south, the Gulcha River flows in a valley 2,000 feet deep. Between this valley and the next there is an upland which in a general view appears to slope smoothly and gently to the north, although it is somewhat notched here and there. The surface of the upland truncates inclined strata which vary in hardness from the resistant oyster-bearing limestone to the soft, shaly sandstones of the Tertiar)-. It is still well preserved, in .spite of the fact that there is in some places a descent of 2,000 feet in 3 miles. The sloping upland plain nuist have been formed as a peneplain, and must have been given its present inclination at a somewhat recent date. In the western part of the Tian Shan range, where the plateau character is less marked, and in the main range of the Alai Mountains, the old peneplain is shown chiefly in the level crests of the ridges. Kven in the lofty Pamir there are certain ranges where the snowy peaks are smoothly truncated, as though by the old peneplain, in spite of the fact that they are from 15,000 to 20,000 feet high. The fragments of old surfaces are indeed so numerous that it seems safe to conclude that much of the country was once reduced to a peneplain, and the rest of it at least to the stage of late maturity- The extent of this degraded region was fully 100,000 square miles — that is, at least 400 miles east and west and 250 miles north and south, and probably much more. Although the age of the peneplain is not closely fixed by the evidence of fossils, it may be referred to the end of the Tertiary, because its erosion was completed after practically the whole Tertiary series of the region had been laid down and warped. For the present we shall consider that the erosion of the peneplain marks the close of the Tertiary era and that the Quaternaiy is introduced by the succeeding changes of elevation. RECONNAISSANCE IN CENTRAL TURKESTAN. 169 THE QUATERNARY UPLIFT. The first process which belongs to recent or Quaternary geological historj- was a vast uplifting of the Tertiary peneplain, the area of the uplift probably extending considerably outside the limits of the region which we are now studying. Coupled with the uplifting of the peneplain as a whole, there was a warping by which it was deformed into basins, large and small, with intervening swells or ridges. As far as was observed, this warping does not seem to have initiated new lines of stress, but to have confirmed old ones of Tertiary age. In the old movements faulting took place abimdantly ; in the new movements warping was the nde and faulting took place rarely. The Quaternary- basins seem to be revivals of fonner basins, first formed early enough to receive Tertiary deposits, for the Tertiarj- strata usually appear to have been deposited in basins similar to those which they now occupy, but less deep; that is, the strata are thickest in the center and grow thinner toward the edges, where also they are more warped, as though the edges of the basins had been gradually raised out of the area of deposition. The scale of the Quaternary warping was large, for some of the ridges, such as the main crests of the Tian Shan plateau and of the Alai range, were raised over 10,000 feet above the bottoms of the neighboring basins. The Qtiaternar)' uplift gave to the country the general form which it now possesses and divided it into portions which have distinct characteristics and may therefore be treated as natural physiographic provinces. Consequent Drainage. — Before discussing the provinces separatel)', a few words should be said about the drainage and the evidence which it gives regarding the condition of the land previous to the Quaternar}- uplift. Throughout Central Turkestan the drainage is almost iniiversally consequent upon the Quaternary- warping, although in some places where the strata are soft the beginnings of a subsequent drainage are seen in process of development. The main streams follow- the axes of the basins parallel to the general strike and lea\'e the basins through gorges which seem to be located where the rims of the basins sag. Most of the basins contain Mesozoic and Tertiary- strata, and the main streams usually tra\-erse these weaker formations, so that from a mere inspection of a geological map they might seem to be subsequent. It is in the tributaries that the true consequent character is seen, for they flow down the slope of the warped peneplain surface and across the strike of both hard and soft strata. In the old age of the country previous to the Quaternary' revival the main streams probably followed somewhat the present lines ; for most of the basins, as has already been said, had been fonned earlier by the down-faulting or folding of blocks of Mesozoic and Tertiary strata during the pre- vious times of deformation, and at late maturity many streams must of course have searched out the softest formations. The altitude of the peneplain may then have amounted to thousands of feet because of its greatest distance from the ocean, but it must have been far lower than now. The hard rocks, the granite and the Paleozoic limestones, fonned the uplands as they had done for ages and as they do to-day. At present there seems to be no sign of an old subsequent drainage in these uplands, a fact which indicates that the country- was so far reduced to a peneplain that the streams paid little or no attention to structure. I-O EXPLORATIONS IN TURKESTAN. LONG CONTINUANCE OK PROCESSES OF DEPOSITION AND UPLIFT. In the precediii.a;' sections the varioiis rock formations and the Tertiar>' peneplain have been spoken of as though each of them represented a definite space of time rather than a stage of development. That the latter is the truer view is well shown by the phenomena along the borders of the Kashgar basin. South of the village of Artush, about 12 miles northeast of Kashgar, the Quaternary plain is broken by a ridge of interstratified silt and gravel which runs nearly east and west and rises 200 or 300 feet. It is an anticline so recently uplifted that its original form remains almost unchanged, although the material is soft and unlithified. The dip is gentle, about 6° on the north side and less on the south. The greater part of the strata which compose the anticline consists of buff silt, which is like loess in color and te-xture, although some portions at least are more clayey. It is apparently the same material as that which is now being deposited in the plaj-as of the surrounding plain. Interstratified with the silt are layers of stream gravel, showing old channels with cross-bedding and lateral unconfonnities. The top of the ridge is covered with gravel from 5 to 20 feet thick. West of Kashgar the silt continues, although with less of the character of loess. The vallej' followed by the caravan road to Osh leaves the plain through some low hills which seem to be a continuation of those already described near Artush. The)- consist of the same silts and graN'els, which dip greath- toward the plain and are well exposed in the steep sides of the valley. At the top lie several hundred feet of grave], then come numerous alternations of gravel and silt, \\ith a gradual increase in the thickness of the finer material, and at last ver}- thick yellow silts. The upper part of the latter are full of lenticular stream-channels, which grow broader and less numerous lower down. Although all the strata are verj* soft, they correspond in position to the fonnations whicli have been described above as the brown conglomerate and brown sandstone of the upper Tertiaiy, and by the rules of ordinary stratigraphy would be reckoned as of the same age. That they are younger is shown by their less degree of consolidation and by the fact that they can hardly be distinguished from the strata now in process of formation. Their folds, too, are younger than those of the sandstones, for although they rise above the level of the old peneplain, they are not beveled by it. Apparently, the Kashgar basin has long been growing smaller by a process of continuous folding along the edges, and as it has grown smaller the locus of deposition of the gravels which accumulate along its edges has gradually been pushed iu\\-ard. To make this more concrete, let us take the cross-section at Sugun Karaul, west of Shor Kul (fig. 124). In the Tian Shan plateau, 10 or 15 miles from the edge of the Quaternary plain of the Kashgar basin, the conglomerate at the top of the Tertiary- is highly folded and ver>- hard, but as the same stratum is traced southward and westward it becomes softer and less folded, until finally it seems to run into the soft gravel of verj' recent date which has been described in the preceding paragraph. Moreover, the old resistant conglomerate of the Tian Shan region has been smoothl\- baseleveled since its severe folding was completed, while the gentle folds of the soft young gravel have only been dissected by narrow valleys which have not yet pro- duced a maximum of relief This seems to mean that somewhere in Tertiarj' time RECONNAISSANCE IN CENTRAL TURKESTAN. I7I the border of the Kashgar basin was 15 or 20 miles north of its present location, and was a place of heavy gravel deposition. Then a small fold de\-eloped along the border, lifting up part of the gravels and causing the accelerated streams to deposit their load of pebbles farther toward the center of the basin, where playas had formerly deposited silt. Later another fold was developed and the gravels once more ad\-anced, and so on by steps which were perhaps too slow to be noticed. The older gravels were compressed and hardened into conglomerates and their upper portions were woni down to the smooth grade of the Tertiary peneplain. A similar experience befell all the underlying fonnations. Each of them, and the peneplain as well, represents not a certain time, but a stage in development, and some of the stages are not yet completed. PHYSIOGR.\PHIC PROVINCES. THE TIAN SHAN PLATEAD. The part of Central Turkestan traversed by the writer divides itself naturally into four provinces — namely, the Tian Shan plateau, the Alai Mountains, the Kashgar basin, and the Fergana basin. The first of these is generalh- tenned the Tian Shan ^Mountains, but as far as the province was seen, it is not strictly a mountain range according to a scientific definition, nor is it strictly a plateau. It is a region of mountainous structure, and once of truly mountainous form, but it long ago reached old age, and has since been uplifted to its present height with relati\-ely little renewed folding of the strata. In structure it is still mountainous, but its present form and altitude are due to an uplift of the unifonn kind which is usually associated with the formation of plateaus. To-day it may best be described as a plateau; to-morrow, geologically speaking, when all the remnants of the uplifted peneplain surface and the last of the post-Paleozoic strata have been removed and dissection has gone far enough to produce strong relief, it will again become a typical mountain region of highly folded limestones. The general structure is shown in the accompanying section (fig. 124), which is about 200 miles long and extends south-southwest from the mouth of the Juuka Su, 25 miles west of the east end of Issik Kul, to the Kashgar desert at Sugun, 30 miles west of Shor Kul. The section represents the general character of the plateau in its least dissected portion. Farther east and farther west the surface is more deeply trenched by the main streams. Along the section the profile is essentially a ver\- broad anti- cline of the Uinta type, as defined by Powell, where the sides are monoclines and the top is flat. The fact that the component strata were already highly folded does not alter the character of the last uplift, although it makes it less evident in the cross- section. If the line representing the surface is looked at alone, the true nature of the deformation is evident. The anticline is not strictly flat on top, but undulating. The troughs form broad basins at an altitude of from 10,000 to 12,000 feet, while the crests fonn broad ridges which reach a height of from 13,000 to 15,000 feet. On the steep northern slope of the broad anticline the valleys are fairh- open at the base where the>- reach the Tertian- strata of the Issik Kul basin, but the\- are for the most part narrow canyons with inaccessible walls of naked rocks 172 EXPLORATIONS IN TURKESTAN. o S s. H 5~ 7^ i s n S g a. a. •o o a o a 5- wo> o , B) W O ' (ft r ^^- bounding a flood-plain so narrow that in the valley bottom a road with difficult}- finds a place among the cedars and mnst often cross the cascading brook or even climb out of the valley. Between these young valleys the graded northern slopes of the broad anticline are covered with cedars, which form the only forest seen during the whole journey. Far up the stream, where glaciers have been at work, the valleys widen and are better graded, and at the same time the interstream areas become rougher, although they still contrast strongly with the valleys. The }outh of the latter is shown not only by the steepness of the walls, but by the relatively moderate depth, i,ooo or 2,000 feet, which seems to be the most that they have as yet attained beneath the interstream highlands, although the streams descend very rapidly and are cutting actively. Another evidence of youth is seen in a nonnal hanging valley from which a small side stream cascades 40 or 50 feet directly into the Jukiichak Su, whose narrow valley here has no flood-plain whatever. The broad ridge which lies along the northern border of the Tian Shan plateau is always covered with snow, and most of its passes are occupied by glaciers. A few of the summits have been sharpened into peaks by glacial action — after the fashion described for Alpine peaks by Richter — and are worth seeing as attractive examples of Alpine scenery, but most of them are mere remnants of the old peneplain, separated by broad, but not very deep, valleys of glacial origin. The uniformity of summit height is illustrated by the excellent topographical map con- structed by tlie Russian general staff" on a scale of 2 versts (iy2 miles) to the inch. Out of 43 summits, of which the elevation was given on three contiguous sheets at the eastern end of Lssik Kul, 32 reached an elevation of from 13,000 to 14,000 feet, and the highest reached 15,069 feet. As soon as the broad ridge of the northern border is crossed the country assumes an aspect which fully justifies the tenn " plateau." At Jukuchak pass, for instance, the narrow young valley which one ascends in traveling southward from lssik Kul is exchanged for a broad, open, elevated plain, bounded on all sides by snowy mountains, whose slight dis.section causes them to suggest a block of marble on which the sculptor has rudely outlined a form but on which he has as yet carved few details (see fig. 1 25). The treeless plain with its cover of brown or green grass has the thoroughly graded aspect and subdued slope of a region in late maturity ; and such it is in spite of its elevation and potential youth. So far as erosion is concerned it only waits for some stream to cut headward through the sur- rounding ridges to cause it to enter upon a new cycle at the very beginning of youth. The Yak Tash basin, southwest of 3 3- C_ 015. 5^ 5i'/sff RECONNAISSANCE IN CENTRAL TURKESTAN. 173 the Jukuchak pass, is full of old moraines spread in a broad, uneven sheet and inclos- ing numerous lifeless ponds and lakes. In other basins the moraines have not advanced so far and the streams have cut slight terraces in the gravel silt or the Ter- tiary strata which lie on the floor of the depressions and fonn the plains. Such in general are the basins and ridges of the most typical portion of the Tian Shan plateau. In the very center of the plateau is a valley of erosion of quite a different char- acter. South of Chakur Korum pass the Kara Kul River, one of the main branches of the Narin, flows in a young valley 1,000 or 2,000 feet deep, with a narrow bottom and steep walls like those which characterize the valleys on the north .slope of the plateau. The road descends from the pass to the river by a narrow side valley with walls a thousand or more feet high, and in some places perpendicular Fig. 125. — Scene in the Yak Tash Basin, in the northern part of the Tian Shan plateau, looking northwest. In the foreground the basin-floor is covered with a flat moraine holding numerous ponds : beyond are smooth-topped mountains cut by glacial valleys. for several himdred feet. Near its mouth, where the flood-plain widens a little, the valley is suddenly blocked by a barrier nearly 200 feet high, lying directly across the path of the stream. This barrier is the moraine of a little glacier tenninating far up on the precipitous side of the valley. The moraine is so porous that the stream flows directly through it with no apparent check, although the gra\-el flood-plain above the barrier is broader than below. Among the elevated basins of the Tian Shan plateau one of the largest is that of the Mudirum Su. Its upper portion is a desert of old morainic waste unrelieved by vegetation ; the lower portion is also full of moraines, but they are 174 EXPLORATIONS IN TURKESTAN. well covered with grass and by contrast seem fertile. The niountaiiis on the southern border of the basin reach a height of from 15,000 to 17,000 feet and have been carved into truly Alpine forms by numerous large glaciers. Another basin is that of the Ak Sai and Chadir Kul (Tent Lake), where glaciation has played a rela- tively small part. The ridge south of this basin forms the Chinese border and has already been described. The valleys descending thence to the Kashgar basin are of the .same nature as those on the north slope of the plateau toward Issik Kul. They are cut in somewhat softer strata, however, and hence are wider, and for the same reason the interstreani areas are more dissected into sharp hills. Vegetation is almost absent because of the dryness of the climate, and the older contorted limestones and slates stand naked in black and gray, while the later strata are bright with red, pink, and green. Chadir Kul. — The lake of Chadir Kul, at the head of the Ak Sai l)asin, near the southern side of the Tian Shan plateau, is a small sheet of water about 16 miles long by 6 wide. It is in the midst of a barren, mountain-girt plain, and does not over- flow, in spite of the snowy heights that surround it and of a drainage area which, according to the Russian maps, is five times as large as the lake itself This has not always been the case, however. The plain of Chadir Kul is composed largely of fine silt which could hardly have been deposited by aggrading streams so near their moun- tainous headwater area, but which might easily have been deposited in a lake. In one place a cut some 15 feet deep along the side of a brook discloses iine silt full of sphagnum, on which rests a little gravel. The lake formerly had an outlet at the head of the Ak Sai basin, where the plain contracts to a distinct channel about a third of a mile wide, bounded on either side by a terrace 40 or 50 feet high. Across the mouth of this outlet lies a little ridge of sand and gravel 10 or 15 feet high, apparently an abandoned and dissected beach. It does not e.xteird quite to the northern terrace, being separated from it by an open gap of 200 or 300 feet. Appar- ently the outlet was first stable long enough to allow the cutting of the broad valley and the terraces on either side. Then a change of some sort caused the building of a beach and the partial closing of the otitlet, through which, however, a stream still ran for a time before another change caused the lake to retire to its pres- ent level. Around Chadir Kul itself nothing was seen to show what these changes were and why they occurred. From the evidence of other places, which will be discussed later, the changes seem referable to alternate expansions and contrac- tions of the lake under the influence of glacial epochs and inter-glacial epochs. The outlet of the lake is later than at least one epoch of glacial action, for while the terrace on the south side of the broad channel is composed of ordinary gravel, the other terrace consists partly of moraine stuff full of bowlders of schistose slate ranging up to 3 or 4 feet in diameter. This must have come from the valleys just to the north, where there are other moraines, and it ma>- have blocked the outlet and caused the lake to expand. The lake as a whole, however, seems to be due to a slight swell or bulge in the basin floor between the Ak Sai basin and its contin- uation in that of Chadir Kul. RECONNAISSANCE IN CENTRAL TURKESTAN. 175 TBB KASBGAR BASIN. South of the Tian Shan plateau, the second province, the Kashgar basin fonns the western part of the vast inner basin of Asia, known as the Takla-Makan and the desert of Gobi. Its flat, barren surface lies at ,an elevation of from 3,000 to 4,000 feet above the sea and is ever^'where surrounded by lofty mountains. Those on the north and west rise from 10,000 to 15,000 feet above it, while to the south- west and south, in the Pamir and Kuen Lun, the heights are even greater. Muz-tagh-ata, one of the world's highest mountain peaks, is plainly in sight from Fig. 126. — View of the Tertiary strata on the edge of the Kashgar Basin west of Kashgar City. The layers here dip northwest away from the basin, which hes behind the observer. On the left several portions of an old grade plain probably represent the work of an early glacial epoch. Kashgar, towering above clouds to the tremendous altitude of 25,800 feet In few other parts of the world can so great a contrast of relief be seen at a single glance, for the parched plain in the foreground lies 21,500 feet below the snowy mountain peak. The lower part of the slope from the mountains to the plain, where I saw it on the north and west sides of the basin, consists of the upj^er Tertian,- fonnations (see fig. 126), while farther back toward the mountains lies the Mesozoic series. All the strata are deformed, but on the edges of the plain the outward dips are lessened, and the Tertiaries assume the fonn of a monocline with decreasing dip, pitching gently under the fonnations which are now accunnilatiug on the plain itself. If the dip keeps on decreasing under the basin floor, as seems probable, the Tertiary strata must soon become conformable with those of the Quateruan-. I 76 EXPLORATIONS IN TURKESTAN. SUBSIDIARY BASINS. On the border of the great Kashgar basin lie several small basins of similar origin. Three of these were seen, of ■which tlie largest and most important, that of Shor Kill, will be treated at length when we come to the consideration of recent climatic changes. For the present it is enough to say that Shor Knl occupies an inclosed basin lying between flat-topped monntains, foot-hills of the Tian Shan platean. It appears to ha\-e been formed by simple warping of the crnst without faulting, l)ut this can not be stated definitely, as it was impossible to make a com- plete circuit of the basin. The floor is a marshy plain, in the center of which is the verj- shallow salt lake. The other two basins, those of IVIin Yol and Kuzzil Oi, are traversed by the main caravan route to Fergana, and lie respectively 30 and 50 B s ^^^^^^^^^^^T^^^^^S^^f^ I^SS" - ^^^--^Vji' — 'Je^ Fig. 127. — Fault scarp on the soulhern side of the Kuzzil Oi Basin, with a smooth deposit, ot silt lying in h'ont of it. miles west by north of Kashgar. They are 8 or 10 miles long and are filled with a smooth fluviatile deposit sloping from north to south. On the north it interlocks with the spurs of the mountains in normal fashion, exhibiting bays of gravel alternating with promontories of rock. On the south, on the contrary-, the under- lying rock rises suddenly and steeply in a straight-fronted ridge without spurs or bays (fig. 127), through which the outflowing streams have cut steep-sided and nar- row gorges. In the case of Min Yol the material that fills the basin is apparently all gravel ; the ridge at the south, as observed at a distance, seems to have been produced by folding rather than by faulting. The Kuzzil Oi basin, on the other hand, is filled in the lower part with fine silt, level and swampy (fig. 127), and the RECONNAISSANCE IX CENTRAL TURKESTAN. 177 ridge to the south presents a steep north-facing fault scarp in the central portion, although farther west this merges into a fold. A peculiar feature of these basins is the drainage, illustrated in fig. 128. In the main, the drainage of the Kashgar region is consequent, with the master stream flowing eastward toward the center of the Kashgar basin and the smaller streams flowing at right angles to it ; but along the line of the smaller basins this simple arrangement is interrupted. A continuous valley runs parallel to the main stream and north of it, but instead of being occupied by a single stream it contains three, A, C, and D, and a fourth, B, taking its rise in the western basin, flows across it. The latter stream is easily explained. The tine silts of Kuzzil Oi indicate that the up-faulting of the barrier on the south proceeded rapidly enough to convert the basin into a lake. This was drained by the short stream B, which has only had time to cut a very narrow gorge through the uplifted mass, even though it is composed of Fig. 128. — Drainage of the Kuzzil Oi and Min Yol basins. the softest of strata. The further study of these basins and their drainage, together with the verj' complete geological section exposed near by and the coal mines worked b\- the Chinese at Kan Su, offers an interesting field of work. The main portion of the Kashgar basin, as is well known, is a smooth desert plain. On the edges broad slopes of gravel are soon left behind, and the floor of the basin stretches sea-like to the triie horizon. It is composed of horizontally stratified sand and silt, entirely free from gravel. The surface is often an immense playa, devoid of vegetation and covered witii a deposit of alkali like new-fallen snow. In some districts the surface is thickly strewn with dunes, each topped with small green shrubs a foot or two high. The latter seem to be the cause of the gathering of tlie silty .sand into the dunes, for where the shnibs are dead the dunes are being destroyed, and dunes were seen without shrubs, either living or dead. Elsewhere the plain of the basin floor is less desert and is covered with a low growth of weeds, bushy and tough, from 6 to 24 inches high. The central part of the basin, the real sand desert, lay south of my line of travel. In the peripheral region the nniddy streams are incised from 10 to 20 feet between slightly terraced walls, although all but the largest soon leave their valleys and spread out in playas. 178 EXPLORATIONS IN TURKESTAN. LOESS. The plavas of the Kashgar plain are connected with the interestinj^ geolojjical problem of the origin of loess. The deposits of the playas greatly resemble certain older dci^osits, having all the typical characteristics of loess; and a com- parison of the two at once raises the question whether loess may not be in certain cases an aqneons deposit, formed on the flat floor of basins or aggraded valleys where streams laden with the very finest silt spread out into thin ephemeral sheets. In a previons section mention was made of an anticline of very recent date lying south of the village of Artush, near Kashgar. It was stated that this anticline is composed of gravel interstratfied with a light yellow material, which is there termed silt becau.se of its relation to the gravel, but which has all the characteristics of loess. If it occurred without the gravel it would at once be pronounced loess. South of the anticline, near the city of Kashgar, the whole country- is composed of what looks like typical loess. It stands in i)eq:)endicular walls wherever it is dissected, and deep trenches are worn in it by the roads; everywhere a close examination of the loess walls shows a faint banding ; slightly sandy lasers and, occasionally, little lenses of fine gravel are found interbcdded with the silt. Further west in similar deposits heavy gravel overlies and is interstratified with layers pos- sessing the essential characteristics of loess, although the}' can hardly be of jeolian origin. In two other basins, those of Fergana and Issik Kul, deposits of loess were seen, which included gravel-filled channels. These facts suggest that loess may be a playa formation and that the Kashgar basin may be a place where loess is still in process of deposition. THE ALAI MOUNTAINS. Of the two remaining physiogra]ihic pro\-inccs little need be said, for in essen- tial features they are repetitions of the Tian Shan plateau and the Kashgar basin. The Alai province includes not only the Alai Mountains proper, which run east and west between Fergana and the Pamir, but also the cross-ridge which runs northea.st from the Pamir to the Tian Shan plateau, with some peaks rising to a height of 18,000 feet. The Alai range is a portion of the old peneplain tiplifted thousands of feet into an arch. It is round on top instead of being somewhat corrugated like the Tian Shan plateau. Its width is nuich less than that of the latter, and it lacks the broad upland basins of warped peneplain, which are so characteristic of the Tian Shan plateau. The Alai has, to be sure, a series of small valley basins on the north and the great Alai basin on the south, but these are all chiefly due to modeni erosion on weak strata that were infolded before the completion of the Tertiary peneplain, (xood examples of the small basins are seen on the Terek Su at Guristan, on the Ak Bura at Bopan, and on the Ispairan at Pum. All of the basins appear to be places where soft strata had been faulted down previous to the completion of the Tertiar}- peneplain ; hence, before the uplift of the peneplain, the down-faulted weak strata were inaccessible to the processes of erosion. Since the uplift, deep valleys with broad flood-plains have been eroded in the weak strata, and the surrounding country has been reduced to the stage of mature relief with thoroughly graded slopes. In the more resistant limestone RECONNAISSANCE IN CENTRAL TURKESTAN. 179 areas which constitute most of the northern slope of the Alai range the old pene- plain is often well preserv^ed and the valleys are ver\' young in aspect (fig. 129). Some of the rivers flow in magnificent canyons; that of the Ak Bura, which reaches the plain at Osh, is 1,000 to 2,000 feet deep, and so narrow at the bottom that the river runs between walls of solid rock in many places and the trail has to clamber on the side walls on a scaffolding of logs filled with stones (fig. 130). The crest of the range resembles, the ridges of the Tian Shan plateau. In the near view, where one looks upward from a valley, the country seems in the highest degree rugged and deeply dissected, but in the large view from a lofty or distant Fig. 129. — Gorge of the Ispalran in its lower portion, where it begins to widen as it flows northward (rom the Alai Mountains to the Fergana Basin. The valley is filled with gravel, in which the stream has cut terraces. station it is seen that the mountain crest is very even and that there are large areas where erosion has as yet accomplished but little in dissecting an old surface of moderate relief. THE ALAI VALBEY. South of the Alai range lies the Alai Valley, the largest of the minor basins. It seems to be due in part to the warping since the time of the peneplain, but nnich of its depth is due to Quaternary erosion working on soft Tertiary strata which had previously been faulted down, as in the case of the smaller basins. The drainage is strictly consequent to all appearances. The master stream, the Kuzzil Su,* nms ♦The name Kuzzil Su or Red River recurs continually in countries where Turkish languages are spoken. At the moment of writing, I recall seven Kuzzil Sus which I have visited during the journey described in this paper. i8o EXPLORATIONS IN TURKESTAN. westward near the uorthern side of a valley 8 or lo miles wide and 60 miles long. Like most of the streams in the valley basins, whether large or small, it wanders freely over its broad gravel flood-plain in a score of intricately braided channels. At the edge of the flood-plain, on either side, is a terrace 20 or 25 feet high, above which are many miles of gravel sloping smoothly from tlie base of the mountains to the edge of the terrace. The broader slope is on the south, where lie the higher Trans-Alai Mountains. They form the northern front of the great Pamir plateau, Fig. 130. — Limestone Gorge of the Western Kichik Alai, where it enters the Ispairan River on the north side of the Alai Mountains. Probably the upper portion of the gorge was widened by a glacier, and the narrow slit at the bottom represents post- glacial cutting. The main valley, from the side of which the photograph was taken, is clearly of glacial origin, and the side valley must have borne a hanging relation lo that of the master stream. rising from 15,000 to 23,000 feet above the sea and from 9,000 to 14,000 feet above the valley. On the north also the mountains are by no means low, for the snowy crest lies at a height of about 14,000 feet, and glaciers are numerous. Near the western end of the valley basin, where it narrows before the stream enters the fine gorge which forms the boundary^ of the khanate of Bokhara, the water wells up from a subterranean course under the heavy gravel deposits and bursts forth in numerous great springs, crystal clear, but very dark. One of these at Mama gives rise to a RECONNAISSANCE IN CENTRAL TURKESTAN. l8l stream so large that it may be truly called a river. Tradition (the tradition found in almost every eastern country) says that this is the outlet of the inclosed lake Kara Kul, lying 75 miles to the southeast, on the Pamir, at an elevation of 12,400 feet. The chief interest of the Alai basin lies in its old moraines and terraces, which will be discussed in due season. Of the regions seen by the writer in the heart of Asia none is more interesting than the Alai Valley. Its magnificent scener>' and splendid climate on the one hand are only less excellent of their kind than are the opportunities for studying the epochs of the glacial period, tlie moraines and ter- races which bear witness to them, and all the phenomena pertaining to glaciation, past and present. Not far to the southwest the salt deposits of Altyn Mazar are of the first importance geologically and economically, and various natural sections present fine opportunities for the study of the rock series ; while to the southeast Peak Kaufmann rises 23,000 feet, with Lake Kara Kul on the Pamir beyond it. Moreover, the Alai Valley is inhabited by a peaceable and most interesting folk, the nomadic Kirghiz, with whom it is well worth while to become acquainted. Besides all this, the valley is relatively accessible, as it is only three days' journe)' from the railroad at Marghilan ; and, lastly, it is practically virgin ground. THE FERGANA BASIN. In outward appearance the last of the four provinces differs widely from its companion, the Kashgar basin ; but the difference is only superficial, resulting from its moister climate. The Fergana basin seems green and prosperous ; its many streams are utilized by an irrigation system which sustains populous villages and cities. The Kashgar basin is chiefly a drear}- desert. Yet in structure the two basins are so nearly identical that detailed description of the second would in\olve repetition of much that has been said about the first. The Fergana basin is an aggraded depression, due to local down-warping and burial of the Tertiary pene- plain. The mountains inclosing the basin are uplifted and more or less dissected portions of the same peneplain. As in the Kashgar basin, the warping by which the Fergana basin was formed seems to be a late phase of long-continued move- ments, during which the mountain area has encroached upon the basin area; for the gradually rising mountains around the basin consist of granite and limestone in their higher parts and of weaker Mesozoic and Tertiary strata around the margin next to the basin, all these having been folded and worn down to moderate relief before the present basin was formed. It is therefore quite possible that the down-warped floor, on which the Quaternary- deposits of the Fergana basin lie, was not ever}-- where a peneplain of Tertian,- erosion ; its central part may well have been an aggraded plain of Tertiary deposition. The periphery of the Fergana basin is sheeted with gravel which grows grad- ually finer until it merges into the fine alluvium of the central plain ; the area of fine alluvium is much smaller than that of Kashgar and has no pla)-as. Many streams cross the plain, with broad flood-plains of gravel between low terraces, while here and there rise hills more or less carved in masses of interstratified silt and gravel thrust up as folds in recent geological time. l82 EXPLORATIONS IN TURKESTAN. THE QUATERNARY PERIOD. Ill our survey of Central Turkestan we have found tluit its geological history was long characterized by a remarkable unit>'. The geological series is uniform in the main, though not in detail. Much of the country- in late Tertiary time was reduced to tlie stage of mature or old topography ; and now, after broad deforma- tion, the basins continue to be aggraded plains, and even the mountains retain much of their Tertiary maturity, although exhibiting marked results of revived erosion. When the country- was divided into strongly marked provinces by the Quaternary defonnatioii, a considerable diversity was introduced between the mountains or plateaus on the one hand and the basins on the other. Both the pre- Quaternarv uiiitv and the Ouaternar)- diversity were due largely to internal causes — to tectonic movements or to lack of movement. In the remainder of this report I shall consider a series of changes of a different character, which seem to have nothing to do with movements of depression or elevation, but appear to depend upon external controls. The changes now considered were climatic and seem to have affected all parts of the country at the same time, although in different ways. As the changes continued to take place through a large part of Quaternary time, they furui.sh the basis for a definite time-scale of wide application. They involve a series of oscillations between glacial and interglacial epochs. The plan of study outlined by Professor Davis at the beginning of our work in Turkestan directed attention to the evidence of possible climatic changes shown (i) in ancient moraines; (2) in terraces, especially along streams flowing from moraines; (3) in lakes and lake deposits ; and (4) in deltas and flood plains of streams which do not reach the sea. In examining evidence of the first three classes it was found not onlv that climatic changes have occurred, but that there has been a series of changes of decreasing se\erity ; it has, however, not yet been possible to correlate exactly the changes shown by one class of evidence with those shown b}' another. In the fourth class there should also be indication of climatic changes if the facts elsewhere olxserved have been rightly interpreted, but as yet this cla.ss of evidence has not been detected. GLACIATION. DISTRIBUTION OF GLACIERS AND AMODNT OF EROSION. During the two months' journey from Issik Kul to Marghilan a considerable number of glaciers, possibly fifty, were seen among mountains ranging from 14,000 to 18,000 feet in height. Most of the glaciers were small and ended close to the ba.se of their cirques. The largest was that of Khoja Ishken* in the Alai Mountains, close to the Bokharan boundar}-, at the head of one of the innumerable Kok Sus or Blue rivers. It is a small example of the vallej* type of glaciers com- monly associated with the Alps. Its length, so far as can be judged from very incomplete maps, is 5 or 6 miles. None of the glaciers descend to a low elevation, *0n the Russian map, scale 10 versts to the inch, this is called the Adramova glacier, but as the Kirgphiz in the neighborhood use the name Khoja Ishken, I have adopted the latter. RECONNAISSANCE IN CENTRAL TURKESTAN. 183 and in the Tian Shan Mountains, where the greater number were seen, the ice rarely descends much below a height of 12,000 feet. Among the Alai Mountains the Khoja Ishkeu glacier comes down to an altitude of about 11,500 feet, while others stand higher ; and even the largest of those on the north side of the Pamir, descend- ing toward the great Alai basin, comes down only to an altitude of 10,500 feet. In former times, however, these small glaciers were much expanded, so that the Altyn glacier, one of those on the north slope of the Pamir, stretched out 20 miles ; those of Yak Tash on the Tian Shan plateau and of Khoja Ishken in the Alai Mountains both reached a length of 30 miles; and the Mudirum glacier on the Tian Shan plateau must have been nearly 50 miles long at the time of its greatest extent. All these Quaternary glaciers were small compared with those of similar mountains in Europe and America. The lowest of them in the steepest valleys was not able to descend to an elevation below 7,500 feet. The large ones on the Tian Shan plateau did not descend below 11,000 feet — that is, only 2,000 feet below the ice of to-day ; and of those in ordinary valleys, where the ice was free to advance indefinitely down a steep, narrow trough, not one descends over 3,500 feet below the present glacier. No trace of a general ice-sheet was seen. The significance of this will be discussed later. At present it serves to show that the area of glaciation was very restricted and that its effect on the topograph}- of the region is purely local. The effects of glacial erosion will not be described here, since they differ in no essential respect from what has been described under similar conditions in other countries. Bold Alpine scenery- is found among the aretes and three-edged peaks of the southeastern Tian Shan, the cirques of the northern Pamir, and the main valleys with over-steepened walls and hanging side valleys in the Alai range. The green moraines not only provide the traveler with an easy road, but furnish fine pasture for the flocks of the nomadic Kirghiz, whose roimd felt tents one is almost sure to find in summer not far from every old moraine. The most peculiar feature of glacial erosion is the broad troughs cut in the smoothly sloping surface of the warped Tertiary peneplain where it has been uplifted in the Alai Mountains and still more in the Tian Shan plateau. The troughs resemble a series of grooves. They head in cirques in the crest of the ridge and widen and deepen as the branch grooves join the trunk trough during descent, until at the lower end they are typical glacial valleys with over-steepened sides. They may be considered as the elongated form which a cirque takes in an inclined plateau. THE SUBDIVISION OF THE GLACIAL, PERIOD IN ASIA. In America and Europe geologists as a whole have come to the conclusion that the glacial period included several cold epochs separated by inter\-als as warm or warmer than the present. Hence, after finding that old moraines abounded in Central Turkestan, it was of the first importance to learn whether they indicated a similar subdivision of glacial time in Asia ; for if there were several glacial epochs, not only might it become possible to correlate Quaternar}- events in Asia with those in the other northern continents, but a definite time-scale might be establi-^lied which could probably be extended to the lowlands of Western Turkestan. An i84 EXPLORATIONS IN TURKESTAN. unexpected result was obtained in the study of this question. TIr- moraines were found to indicate glacial epochs so numerous that the writer was very slow to accept the conclusions that they indicated. It was not until a considerable number of glaciated valleys had been examined that credence was given to the occurrence of several glacial epochs separated by warm interglacial epochs. It thus appears that there were certainly two and probably five glacial epochs, separated by long non- glacial intervals of ordinary erosion, during which tlie climate was relatively warm. AN OLDER AND A YODNGHR GLACIAL EI'OCH. The less doubtful question of two glacial epochs will be first taken up. The valleys where old moraines were found numbered over twenty, and all l)ut three or four of them were examined up to their heads, or at least up to snow and ice. All, not even excepting the two or three small ones seen at first, show an older and a younger moraine (see Table III), although in some the distinction was but slight. Table III. — Glacial phenotnena of Turkestan, showing the number of moraines in each valley visited and the glacial epoch to which each belongs. Name and location of valley. Nameless valley, south of Son Kul Nameless valley, northeast of Son Kul- . . Tuluk Su (upper), north of Son Kul . . Tuluk Su (lower), north of Son Kul • . . Kashga Su, south of Issilc Kul Ulakhol, south of Issik Kul Jukuchak, south of Issik Kul Jukuchak, western tributary Yak Tash, Tian Shan plateau Chakur Kotum, Tian Shan plateau Chakur Korutn (south), branch of Kara Kul Su. Mudirum (Als Sai), Tian Shan plateau Kosargun (NE. of Chatar Kul), Tian Shan plateau. Nameless valley, west of No. 13 Terek Davan (S. side). Alai Mountains Terek Davan (N. side), Alai Mountains Kichik Alai, Alai Mountains. Kichik Alai (W. side). Alai Mountains. Kauk Bel. Alai Mountains Taka, north slope of Pamir Khoja Ishken (Kok Su), Alai Mountains Bursundu, branch of No. 21 , Alai Moun- tains. Kan Su, north slope of Pamir, in Bokhara Ispairan, Alai Mountains Elevation of base of lowest 10,300 10,700 10,000 10,000 7.400 8.200 8,600 9,300 11,200 11,200 11,300 10.900 11,600 11.800 10.950 10,300 7.900 7,300 11,500 9,700 8,000 9,500 8,500 7.500 Occurrence of moraines. Epoch Epoch I, 11. X 1 X I X I X X X X X X X X X X X X X X X X 0)_ X (» X X X V Epoch IV. X X x" X "x X I X Epoch V. X X X X X I X X X X X X I X X ~x X X (?) X X X I X (?) X X X x~ X X X X~ X X X ~k X X X X X X X X X X Preient VI X X X X (?) X X Elevatioa of foot of present moraine. 11.600 12,600 12,600 12,900 11,500 11,400 10.500 Crosses (X) indicate moraines. Wfiere a cross is on a line the moraine may be of either of the adjacent ages. Braces ( ~- — ■) indicate that though it is possible to distinguish two or more moraines they may be stages of one. The elevaUons are taken by aneroid, and arc only approximate within live hundred feet. RECONNAISSANCE IN CENTRAL TURKESTAN. 185 The simplest case is where a valley contains two moraines, one below the other, as in the valley of Kashga Su, a tributary of the Ulakhol at the southwest end of Issik Kul. Here, at an elevation of 7,400 feet, the lowest altitude at which any evidence of glacial action was seen, the lower portions of an old moraine are buried in valley gravels. The moraine itself consists of bowlders and rock waste of various sizes and kinds, deposited together in the usual glacial fashion. Its higher surface is smooth and rounded to such an extent that the topography peculiar to young moraines is almost obliterated, and the lower portions of the moraine show irregular hillocks and short ridges projecting out of a smooth valley floor of gravel in such a way that a removal of the latter would show the ordinary- kettles of a typical morainic topography. Farther up the valley there is another moraine, entirely separated from the first. It has a younger, fresher appearance, and is not at all drowned in gravel ; hence it must have been formed at a considerably later date than the other; but so far as the evidence of this valley is concerned the younger moraine might be merely a stage of retreat of the older one. In other cases the relation is not so simple. The younger moraine lies, as it were, in the anus of the older, and the two appear to have been formed at widely diiferent times, separated by a long period of aqueous erosion during which the ice retreated farther up into the mountains than the position of the younger moraines. One among many examples of this is found in the Tuluk Valley, north of Son Kul. Near the head of this valley and on its north side are two tributary- valleys, from each of which projects a large body of morainic material which seems to be of two ages. The older moraine of the western or larger tributary- takes the form of a rounded spur with its base at a height of about 10,000 feet. The spur has a long, grassy slope, fairly steep but thoroughly graded, and showing few bowlders. Its morainal character is more distinct on the top at a height of about 10,500 feet, by reason of ridges, imperfect kettle-holes, and other characteristic forms, and also b)' reason of more numerous bowlders. The topography is not fresh, however; the kettles are all drained, the slopes are gentle, there is a well-developed though circuitous drainage system, and the occasional bowlders are well rounded and deca}ed. The stream coming from the mountains has cut through the moraine an open flat-floored valley with graded sides. If this open valley is followed up, it comes to a sudden end at an elevation of about 10,000 feet, and above this level it is filled with a moraine that appears to be of much later date. The steep front of the latter has a slope of 30° instead of about 15°, as is the case in the older companion; there are deep, steep-sided kettles, some of them containing pools of water; drainage is but little developed, and the bowlders are mostly subangular. The stream here flows in a narrow V-shaped valley, the sides of which have an average slope of 35°. Yet the same stream, working just below in the other moraine, in what .seems to be the same kind of material, has carved out a valley many times as large, with sides that slope at an angle of only 22°. The inner, smaller moraine shows all the signs of youth ; the outer and larger all those of age. The two must ha\e been fonned at times so far separated that one moraine has had time to be maturely eroded and degraded while the other still remains young. As to what climatic conditions intervened between those times, and as to whether the two moraines represent two l86 EXPLORATIONS IN TURKESTAN. different ice advances or merely two stages of one advance, the evidence is not so positive, yet it seems to show that the two moraines represent two distinct glacial epochs separated by an epoch of retreat and presumable wannth. The rock floor of the main valley which the older moraine enters seems to have been normally eroded several hundred feet after the deposition of the moraine upon it, and the open valley in the older moraine grades into the newly eroded floor of the main valley. During the normal erosion of the main \alley by its stream the glacier of the side valley can not have stood in a position to deposit the younger moraine, for the open valley cut in the old moraine extends farther upstream than that position, and the young moraine lies in the open valley worn in its predecessor, which forms a terrace above it. Therefore we seem obliged to conclude that after the first glacial adA-ance the ice retreated above the position of the second moraine and only after a long lapse of time again advanced to deposit the younger moraine. FIVE GI,ACIAI. EPOCHS. Let us now examine some of the more complicated cases in which there seems to be evidence of five glacial epochs separated by warmer interglacial epochs. It is only in those valleys where glaciers still persist that we can be certain that the whole series of ancient moraines is or has been represented. Kight examples of this sort were examined, of which two were seen imperfectly. The other six are distinguished by asterisks in Table III, page 184, where the name and locality ol the valleys and the number of moraines in each arc indicated. (i) Moraines of the Jitkucliak I 'alley. — The simplest case here, as in tlie previous examples, is one in which the moraines lie in a series one above the other in a narrow valley whicli has not greatly changed its form since the first glacial epoch. An almost perfect example of this type is found in the Jukuchak Valley (No. 7 of Table III), which may be ascended southward from an elevation of 5,000 feet at Issik Kul to an elevation of over 13,000 feet on the northern edge of the Tiau Shan plateau. The lowest moraine lies at a height of about 8,600 feet. At this point the valley ceases to be the narrow steep-sided gorge which can be ascended with difficulty through its lower part, and becomes broad and easy to follow, although there is no accompanying change of rock structure and no apparent cause for the widening unless it be due to glacial erosion. On the floor of the widened valley a strong terrace is composed chiefly of large bowlders of granite, which could have come only from far up the valley and which are of such size that they could have been brought only by a glacier. The terrace is therefore interpreted as the remnant of a moraine so old that all traces of morainic topography have disappeared. Above the terrace the valley is unincumbered for a short distance; then it is clogged by another moraine which is well weathered and worn, but which still preserves in a subdued condition the characteristic glacial hillocks and hollows. Still further upstream a larger space of open valley is floored with gravel, on which the stream wanders somewhat; next comes another fresher moraine and another open space. Twice more these features are repeated before we reach the modern moraine at a height of 11,600 feet. Thus we have five old moraines and five interspaces. The RECONNAISSANCE IN CENTRAL TURKESTAN. 187 moraines grow fresher and yonnger in form from the lowest to the highest; and a long interval mnst have elapsed between the formation of No. i and No. 5. From the evidence snpplied by other valleys it seems that each moraine represents an advance of the ice after a considerable retreat; so far as the Jukuchak \'alley is concerned, however, the ice might simply have retreated by successive steps and the intervals between tlie steps need not have been of great lengtli. (2) Moraines of the eastern Klioja Ishken I 'alley. — Another valle)-, that of the Kok Su, or better, the eastern Khoja Ishken, shows the same succession of five moraines, which might all have been formed by one glacier in its successive retreats; but here erosion has been more active and the difference in age between the suc- cessive moraines is more marked. The first moraine lies at an elevation of about 8,000 feet at the mouth of the Kok Su, where it enters the Kuzzil Su of the Alai Valley. Like all the moraines of this earlier age, it has completely lost the original glacial topography and is only to be distinguished by the bowlders it contains. These consist of slate ranging up to 1 2 or 14 feet in size, which might have been derived 3, 4, s^nioraiucs of the third, fourth, and fifth glacial epochs. Ill, IV, V=level ot valley floor previous to the third fourth, and fifth glacial epochs. C, D, E— gravel deposited at end of third, fourth, and fifth glacial epochs. Fig. 131. — Longitudinal section of tfie Khoja tshken or Kok Su Valley. from close at hand, and of granite up to 7 feet in diameter, which nuist have been transported at least a dozen miles. The moraine is now entirelj' smoothed off and cut into four terraces. It lies on a thick deposit of river gravel which was probably laid down during the time just preceding the arrival of the ice. The second mo- raine is much like the first, except that it occasionally shows some of the original relief If this valley were examined without reference to any others, these two moraines would be considered parts of one. The third, fourth, and fifth moraines are all distinct and are separated l)y spaces where the valley is open and aggraded. They lie on rock terraces high alxne the brook, which, as it approaches each moraine, plunges into a gorge. In these gorges may be found a good measure of the length of time that has elap.sed since the several moraines were formed. Before discussing this aspect of the problem, however, it will be well to consider the origin of the gorges themselves. This is best explained by means of the accompanying diagram (fig. 131). The line III represents the valley bottom at the beginning of the third glacial epoch. The advancing glacier came down this slope i88 EXPLORATIONS IN TURKESTAN. and paused at 3, where it deposited a moraine. Above this point the ice deepened and broadened its cliannel to the line IV. Tlie erosive action of the glacier ceased where the moraine lay, and the oidy erosion there was that of the glacial stream which began to cut a narrow gorge that bore the same relation to its \olume that the broad valley above bore to the volume of the ice that filled it. Thus the place where the moraine lay became an elevation with reference to the general grade of the valley, and at its upper end there was an actual as well as a relative increase of relief over the upstream portion, where the glacier had been at work. When the ice Fig. 132. —Youngest Gorge ot the Khoja ishken, cut in the Bottom oi the Main Glacial Valley. The over-steepened sides o( the latter show clearly on the right. retired the stream continued to simplify the slope of its bed b)- filling the glaciated hollow with gravel (C) and cutting the gorge still deeper. Three repetitions of these events produced three gorges. Further examples of gorges thus formed were seen in the valleys of Ispairan, Kichik Alai, and elsewhere, although they were by no means so perfect as in the Khoja Ishken \'alley. The glacial scouring of all these valleys seems to have been closely analogous to but less powerful than that by which the fjords and glacial valley lakes of Europe and America are sujjposed to have been formed. RECONNAISSANCE IN CENTRAL TURKESTAN. 189 The two upper gorges of the Khoja Ishken \'alley and part of the lower are cut in a inetamorpluc limestone which sometimes becomes marble, and in each the grade is so steep that the stream is still active!)- cutting downward. Hence the width of the gorges relative to the size of the stream gives a good measure of the time that has elapsed since each gorge was formed. The upper gorge, the one associated with the fifth moraine, is exceedingly young ; so young that though it is cut to a depth of over 50 feet in solid rock it has scarcely widened at all, and the top is but slightly wider than the bottom (fig. 132). It is so narrow in one place that it has twnce been naturally bridged by bowlders. One of these bridges is utilized by the road; the other is a great granite bowlder, 25 or 30 feet in diameter. Fig. 133. — Marble Bowlders, and beginning ot (he Gorge associated with the {ourth Khoja Ishken Cladei. which lies directly across the narrow slit cut by the stream. The next gorge (fig. 133), belonging to the fourth moraine, though not much deeper than the upper one, is decidedly wider both relatively and absolutely, as shown by the accompanying cross-sections (figs. 134, 135). In spite of the fact that it is cut in marble somewhat harder than the limestone of the upper gorge, its sides have a slope of about 45° instead of nearly 90°. In one place it shows a little terrace near the bottom. It seems to be two or three times as old as its successor. The gorge of the third moraine, which is the oldest and the farthest downstream, is so broad that the road runs at or close to the bottom, and the sides have a slope of only 25° or 30° even where it is cut in granite or slaty quartzite. The terrace, which lies 200 or 300 feet above the stream, has been consumed to a mere fringe on the valle>'-side, and I go EXPLORATIONS IN TURKESTAN. the valley floor is choked with waste from tlie moraine and the underlying- rock. The difference in age between this gorge and tliat associated witli llie fourth moraine appears greater tlian be- tween the gorges of the fourth and fifth moraines. Tliis means that between the formation of succes- sive moraines there must have been considerable intervals of ero- sion. Where the glacier stood during these intervals is not clear. It may have retreated above the position of the ne.\t moraine and again advanced; or it may merely have retreated to that ])osition and there remained stationar)-. (3) Moraines of the Afiidinnii Basin. — A third valley, of l)roadly open basin form, drained by the Mudirum Su* on the south side Fig. 134.-<;ross-seclionso( the Khojalshken Valley, to show the shape of the Tian Shan plattaU, sllOWS wl!!,',l7,!!f,'„,l,'''V^'%1°'''!i Drawn (rom observa.,on. q,^ moraiueS of foUr aud probablv without measurement. 1 he circles mdicale moraines. 1 he lightly ' ' shaded portions indicate the amount of erosion since the respective of fivC ageS lying ill regular SC- parts of the valley were filled with ice. . , , • 1 ■ queuce, without any indication as to what happened during the intervals between their deposition or as to whether there were any intervals when glacial deposition ceased. The glacier of this valley is the largest of all those of which the moraines were studied ; it reaches a maximum length of nearly 50 miles. The thick- ness of the ice was so great that at Jubergeiiti pass it overflowed toward the north into the valley of the Kara Kul River. It was not possible to fol- low the Mudirum River to its head, but a side valley was examined as far up as a modern moraine. The relations of the moraines are illustrated in the accompanying sketch map (fig. 136). At the head of the valley are two tiny glaciers, A and B, with little moraines, marked VI. Below these is another moraine, V, which seems to be a little older, but may be merely a stage of VI. In the next valley to the west is a cirque with a ver)' j'oung moraine, V, but no glacier. There is much snow near by, and these little moraines were not well seen. The next moraine, I\', is 500 or 600 feet lower, and is a large semicircular mass of clearly glacial origin. It is composed of limestone Fig. 1 35. — Cross-sections of the three gorges of the Khoja Ishken Valley, to show the amount of widening and erosion of the valley in each case relative to the power of the stream and of erosion without refer- ence to the actual size. *Thc Kirghiz call most of rfiis stream the .\k Sai or White River, and apply the name Mudirum to the lower part only, but the name Ak Sai is alnioit as common as Kuzzil Sti, and as this Ak Sai empties into another Ak Sai, it seems better to use the less common name. RECONNAISSANCE IN CENTRAL TURKESTAN. 191 and slate, and accordingly is well weathered. The brook cnts through it in a narrow valley with steep sides. In front of IV is a nearly flat plain of silt and fine gravel, due to the obstruction of drainage by the next older moraine, III. This lies I >/< or 2 miles in front of IV and less than 200 feet lower. It is well dissected and graded, with kettle-holes only on the edges near the mountains, where it approaches its successor. The stream flows through it in a broad valley. The next moraine, II, is far larger, as it belongs to the whole \alley and not merely to the tributaiy-. It is 4 or 5 miles wide, 10 or 12 long, and several hundred feet thick. Because of its great size and because of its composition of granite, often in large blocks, it is less dissected than its small neighbor, III, but its location shows that it must be older. The stream valley which is cut through it is not of great width, although its sides are well graded. In the downstream half of the moraines the valley is wider and has three terraces. At the very front a moraine of later age, probably corresponding to the third in the above series, comes down from the north and covers the older moraine and its terraces. Below this there is an interval of nearlv 9 miles with no moraines except a few small ones which come Fig. 136. — Sketch map showing the location of the Mudirunv Moraines. from side valleys and do not extend into the central portion of the main valley basin. Large bowlders of granite, sometimes reaching a diameter of 20 or 30 feet, are scattered here and there. The open valley floor is of gentle descent and falls but 100 feet in the 9 miles. Then begins the lowest and oldest moraine, I. At first it is complicated by a side moraine of later date, coming in from the south, but in its course of 7 or 8 miles farther west it becomes more and more smooth and free from surface bowlders and irregularities. Near its end two subangular masses of granite, from 10 to 15 feet in diameter, were noticed lying in the middle of the flat \-alley where they could not have been brought by water. Beyond this it is impos- sible to tell where the moraine ends and the gravel plain at its front begins. Three examjjles have been described in the preceding paragraphs where the ancient glaciers have formed moraines at five different points successively farther and farther up-valley. These moraines may represent successive pauses of one retreat, in which the glacier retired quickly for a certain distance and then stood still for a considerable time, or they may represent distinct glacial advances 192 EXPLORATIONS IN TURKESTAN. separated by wanner intervals of retreat. Tliree examples wU\ now be described which seem to be explicable only on the latter theory. (4) Moraines of the Yak Task Basin. — On the northern side of the Tian Shan platean, south of the ea.stern end of Issik Kul, lies the broad valley basin of Yak Tash, surrounded by snowy ranges whose side valleys head in little glaciers (fig. 125). Starting from one of these glaciers, that of Jnknchak, which is crossed by the road from Przhevalsk to Chadir Kul, let us examine the moraines in detail, beginning with the youngest and proceeding to the oldest, which we find half inclosing the next to oldest. The present moraine is a tiny affair, perhaps 10 feet high, at the foot of a valley-head glacier scarcely a quarter of a mile long and composed largely of snow. Below this is a little jiond, and then the broad, gentle slope of the side valley, which grows wider as it approaches and merges into the the main valley basin. The upper part of the side valley is floored with angular stones, but about 2 ]/> miles from the glacier these give place to a fme horizontally stratified silt, which is now dissected to a depth of 6 or 8 feet. The silt appears to be the deposit of a lake, dtie to the damming of the stream by a moraine lying half a mile down the valley. This moraine is broad and flat, with few kettle-holes. It represents the last of the glacial epochs, the fifth. Below it is Arabel Lake, a sheet of water 2 or 3 miles long, hemmed in by the next moraine, and lying half in the main basin, half in the side valley. The moraine of the fourth epoch is of large size, extending 7 miles downstream, and spreading out broadly on every side so as to fill most of the Yak Tash basin. Under such circumstances the relief is naturally slight The moraine is characterized by low bowlder-strewn hills with gentle slopes, and by broad, shallow dej^ressions, of which twelve or fifteen were seen holding ponds from 200 to 2,000 feet in diameter (fig. 125). The fourth moraine comes to a fairly distinct end near the point where the stream from Juuka pass turns from an eastward to a westward course. Beyond this, however, we encounter a moraine about 7 miles long which .seems to be older than IV (fig. 136), but can not be .sharply distinguished from it. At first sight it suggests a sand plain washed forward from the ice front, but that can not be, as it contains manv bowlders 5 or 6 feet in diameter and some much larger, and in addition to this it increases in height at the lower end. It contains one or two small depressions filled with water, but otherwise its top is quite smooth, and its graded sides stretch evenly down the Jnknchak and Juuka streams, between which it lies as a long tongue. Bowlders crop out but rarely and all are well weathered, with the corners rounded off. Diagonally across the moraine runs what seems to be an abandoned channel of the Jukuchak, 50 feet deep and 400 or 500 feet wide at the top, with a string of ponds at the bottom. The other stream, the Juuka, was so far displaced to the north by the upper part of the moraine that it was caught in a rock-bound channel, where it has now cut for itself a narrow rock gorge. The third moraine lies largely in the upper part of the typically glacial valley that connects the Yak Ta.sh and Kara Sai valley basins. The hills above, except where they have been acted upon b)- glaciers, have gentle mature slopes, which form a distinct angle with the steep and often precipitous sides of the valley. The RECONNAISSANCE IN CENTRAL TURKESTAN. 193 floor of the latter is half a mile wide and verj' flat where it is not cuinl)ered bv the third moraine. Main- of the smaller \alle\s tributarj- to this one are themselves glacial in form and open in the sides of the main valley at heights of 300 or 400 feet, in true hanging-valley arrangement. These features are due to the work of the glaciers of the first and second epochs, and their freshness as compared with the weathering of the moraines is a good witness to the great influence of solid rock as contrasted with rock waste in preserving physiographic fonns. About 6 miles below the junction of the Juuka and Jnkuchak streams, which unite at the end of the third moraine to form the Yak Tash, the valley loses its glacial form and broadens into a basin 5 or 6 miles wide and 8 or 10 miles long. In this lies the second moraine, forming a great horseshoe. It .still retains much of morainal form and has ninnerous undrained basins, many of them filled with ponds. On account of its breadth and flatness, it has suffered less erosion than has its steeper and narrower successor. The Yak Tash River flows through it in numerous braided channels, which wander freeh' over a gravel flood-plain a mile or two broad. So far the moraines of the Yak Tash lie in a linear series like those of all the other valleys that we have considered. The relation of the first and second moraines is qtiite different. South of the Yak Tash 3 or 4 miles the character of the countn,- changes quite abruptly as one passes from the second moraine to the first. On the north is the second moraine, a flat country studded here and there with bowlders and pitted with numerous little holes and irregular depressions. It is very clearly a moraine, for although the slopes are ever>'where well graded, the drainage is irregular and by no means completely established. A belt of country south of this is 100 or 200 feet higher and has a thoroughly established drainage system, to which every part is tributary; the main river has cut a valley several miles wide through this belt. There is not a sign of kettle-holes or other glacial topography and at first sight there is no sign of moraine ; here and there, however, large bowl- ders of slate or oftener of granite from 3 to 6 feet in diameter rise out of the smooth, fine soil, and smaller, angular bits of rock of various kinds are scattered about on the surface. These lie largely on hill tops, where they can have been brought onlv by glaciers, and are therefore to be regarded as belonging to an ancient moraine. The branch and main valleys are 200 or even 300 feet deep, and are cut through the moraine into an underlying deposit of soft silt. Apparently a glacier flowed into this basin .soon after a great deposition of silt had taken place, and becau.se of the flatness of the district the ice spread out broadly and deposited an extensive morainic sheet 10 to 50 feet deep. A period of subaerial erosion ensued, during which the ice retired long enough and far enough to allow. the submature dissection of the moraine and of the underlying silts, and to allow the river to cut a valley 5 or 6 miles wide through both deposits. The ice nuist have stood nnich farther upstream during this epoch of erosion, and at its close must have again advanced to deposit the second moraine in the valley that had been eroded in the first moraine. (5) Afora/ius of the k'ait Si/ ^ r7//<_)'.— In the Kan vSu \'alley all five of the old moraines can be detected in addition to the modern one, but the first and second are not w'ell differentiated and do not need to be considered. The third moraine lies at an elevation of about 9,0100 feet in the triangle between the two main branches 194 EXPLORATIONS IN TURKESTAN. of Kan Su. It shows something of morainic topography, although tliis is not ver\- marked. The slopes are thoroughly graded and covered with grass, and the moraine as a whole is cut by several subparallel valleys, two of which are occupied by streams and have slightly terraced sides, while the others are abandoned, and seem to be stream channels of glacial times. Their heads are abruptly cut off by the fourth moraine, which lies at an elevation of about 9,500 feet, where there is a sudden rise in the valley floor, and where the main valleys which are not beheaded contract somewhat. At the top of this rise lies the distinct frontal ridge of the fourth moraine, horseshoe-shaped and inclosing a depression. The rest of this moraine has a pronounced glacial topography, although the slopes are ])erfectly graded. Moraines Nos. 3 and 4 appear to be of different but not widely sepa- rated ages. The vegetation of both has reached what may be called the stage of complete occupation; that is, they are covered with a fine growth of grass, except in the valleys, where there are some trees. The fifth and last of the old moraines, on the contrary,-, has not reached this stage. It begins at an elevation of 10,100 feet, where there is a sudden change to \er\- rough moraine topography, which seems to be of considerably later date than that on which it lies. Instead of the surface being smooth and grassy and almost free from stones, the rough slopes are covered with angular fragments of rock, among which are scattered cedar trees and a growth of thin, weedy grass quite unlike the turf below. The bowlders, too, are larger, more ntimerous, and more angular than those of the other moraines. The difference between this fifth moraine and its predecessor is more marked than that between the adjacent older moraines. The present moraine at an elevation of 10,500 feet is quite as sharply distinguished from the fifth as the fifth is from the fourth, and the change is of the same sort. The present moraine exhibits in many places a sharp line of division, above which the rock waste is even more angular and fresh than below, and above which there is practically no soil filling the interstices of the rock and hence absolutely no vegetation. Much of the moraine lies as a cover on the ice itself In its lower portion the modern moraine spreads out, so that for a short dis- tance it fills the whole width of the valley. Higher up, however, the moraine, or rather the o-lacier itself with a cover- ing of moraine, lies in an inner valley cut in moraine stuff of an older date. This is represented in the accom- panying cross-section through the valley at an elevation of about 1 1 ,000 feet (see fig. 137). The portion A rep- resents the rock valley composed of "-'"''^ "«"* of valley. B=n.oraine of third or fourth •^ ^ epoch. C=modern glacier. D=niodera moraine. D'=bit limestone below and purple slate of modem moraine winch has overflowed B. above ; B represents an older moraine, F'g- 137.— Cross-section of the Kan Su Valley at an elevation ' ^ . of 11.000 feel. either No. 3 or No. 4, which was formed so long ago that its slopes are thoroughh- graded and are well co^•ered with grass, and bowlders have almost disappeared. Yet it is not so old but that it still retains signs of a morainic topography, though this is so far destroyed that the RECONNAISSANCE IN CENTRAL TURKESTAN. I95 kettles are drained. On the outer edges are valleys where streams probably flowed along the two sides of the glacier, as they often do. The inner slopes of these two portions of an old moraine are verj' steep, as they are now being undercut by the ice, C, on which lies part of the present moraine, D. The slopes show that the material of the old moraine is truly glacial in its angularity and irregularity of size, but utterl)- different from the present moraine in that it is well weathered and that the soil produced by weathering fills all the interstices. In fact, the slopes seem to contain decidedly more soil than rock. At present the modern moraine lies 50 feet more or less below the top of the older ridge, but there are many places where it formerly rose to the top and o\-erflowed, as at D. These facts seem to lead to the conclusion that between the deposition of mo- raine No. 3, or 4, as the case may be — it is quite immaterial which — and the deposition of the present moraine, the ice retreated to a position farther up the valley than that which it now occupies, a.s the following considerations will show. It may, perhaps, be taken as beyond question that a moraine such as B can not ha\e become thoroughly weathered, graded, and covered with grass without long exposure to the air; nor does it require discussion to show that where graded slopes, such as those of B, are being undercut, they must once have extended farther in the direction of the agency which undercuts them. Therefore the ice must for a long time have occupied a smaller space than at present, and since that time it must have widened. But this could not have been possible with a continuously retreat- ing glacier, for it should have suffered a continuous narrowing. Moreover, on the supposition of continuous retreat, with or without pauses, but without readvances, each moraine ought to lie above the one that preceded it, and this seems to be the crux of the whole question. A portion of the third or fourth moraine — let us say the fourth for convenience — lies from 1,000 to 2,000 feet above the rest of that moraine, and from i "^ to 3 miles farther upstream. Between the two portions of the fourth moraine lies the whole of the fifth and most of the sixth moraine. It seems impossible to explain the facts on the theory of one retreat whether at a uniform rate or with pauses. If, on the other hand, each moraine represents an advance and retreat of the ice, the difficulty disappears. The old glaciers were probabh- co\ered with moraine stuff just as the present one is, and as each retreated it would leave a trail of moraine behind it. The glacial stream would carve a \alley in the abandoned moraine during the interglacial epoch. The next glacier would follow this valley at first, though it would widen it greatly, and in most cases utterly obliterate it But each succeeding ice sheet was smaller than its predecessor, and where the valle\- was wide it might happen that portions of the older moraine would be pre- served. This is what appears to have taken place at Kan Su. If tliis interpretation is correct it means that after the fonnation of the main portion of the fourth or possibly the third moraine, the ice retreated so far as to end at least 1,200 feet above the level of its moraine, and so reached a point 700 feet above the present level of the glacier front; that is, the fourth glacial epoch was followed by an inter- glacial epoch decidedly wanner than the present epoch. 196 EXPLORATIONS IN TURKESTAN. lOi Vv^i^^l (6) Moraines of the Taka Valley. — Tlie last valle)- to be described, that of Taka Sii, on the north side of the Pamir, heads in two larj^je cirques on the north slope of the peak of Kliitai Saz, 17,500 feet high. The slope from here to the Alai basin is steep and the stream has been cutting steadily downward all through glacial times and to the present. The cutting has been most active in the soft Mesozoic-Tertiarv strata which lie between the basin and the mountains. As this is the place where most of the moraines were deposited, they too have been dissected; but fortunately none have been entirely destroyed, and the dissection furnishes a means of ascertaining what occurred during the interglacial epochs. The moraines number five, in addition to the one now in process of formation, and all are distinctly separated from their neighbors. We will take them up in order of age, beginning with the oldest. The first moraine is merely a covering of bowlders and finer glacial material lying on the hills east of the Taka Su, at an elevation of from 800 to 1,200 feet above the stream where it debouches on the plain of the Alai basin (fig. 138). The bowlders are chiefly limestone or calcareous slate of the com- mon Paleozoic type, and many are of large size and quite angiilar. The surface of the moraine is completely graded, and shows only a few traces of glacial topography, such as crooked drainage lines and a few detached hollows. The countr}- rock does not crop out through the moraine itself, but on the sides of the valley cut through the moraine the red beds of Mesozoic or Tertiary age, which extend all along the base of the mountains and must underlie the moraine, are seen up to an altitude of 600 feet above the stream. The ne.\t moraine is composed of the same materials as the first. It has clearly the morainal type of topography, although in a subdued and well-graded fonn. Its relation to the others is shown in the accomi>anying sketch map and cross-section (figs. 13.S and 139), where it is .seen Moraines of the Taka that the secoud moraine lies as a narrow terrace in the valley wliich was eroded on the western side of the first, about 400 feet above the stream. The first moraine was formed when the valley had been eroded to a depth much less than now and when the glacier was therefore free to spread over a considerable area. The second moraine was fonned when the relief was much more like that of to-day, and the glacier was closely hemmed in by a well-defined valley. It seems impossible to explain this relation except by supposing that after the first glacial epoch the ice retreated far upstream above the upper end of the terrace and staid there long ■^\\x\\^:^x^ Uns:mdf' which has been advanced bv several writers. Before this h)pothesis can be adequately tested a great array of facts is required not onh- in regard to the old glaciers themselves, but also in regard to rainfall and evaporation and in regard to the changes of elevation which the land has suffered relative to the sea. TERRACES. If during the Quaternar\- era there were climatic changes of such magnitude and frequency as those demanded in explanation of the old moraines, the changes must have left their traces all over the region. vSuch traces can be detected in two situations, namely, the terraces of streams and the deposits of lakes. The most striking feature of the terraces in the valle)'s of Central Turkestan is their wide dis- tribution and uniformity of pattern, without respect to the size or location of the stream along which they occur. They were seen in the vallej-s of swift mountain torrents and along the sluggish rivers of the plains. They occur not oulv in the valleys of tributaries of the Syr Darya (Jaxartes) on the north, and of the Ainu Darja (Oxus) on the south, but also along the streams that wither to nothing in the Kash- gar basin, whether their source be the Tian Shan plateau to the north or the Alai Mountains to the west; and they are found even along the water-courses leading to inclosed lakes. They var}- in number from stream to stream as well as in different parts of the same stream. At the \-er>- head of a valle\- there is naturally no terrace, but as the valley is followed downward, first one terrace appears and then another, until in that portion of the valle)- where erosion has been more active the terraces reach a maximum both in size and number. Farther dowai-valley they again decrease in both respects until finally, far out on the floor of some basin, a single weak ter- race dies out entirely as the stream becomes an agent of deposition rather than of erosion. 202 EXPLORATIONS IN TURKESTAN. The number of terraces ranges from none to nine, but neither extreme repre- sents the true state of affairs. V.'here terraces are absent it is either because the slope of the streams is so gentle that there is no erosion or because the slope is so steep and the country- rock so resistant that the streams lia\-e as yet been able to cut only narrow gorges. Where the number is over five the material is usualh- uncon- solidated gravel, and some of the teiTaces are usually .small and seem to be mere stages of larger ones. Ordinarily there are from three to fi\-e terraces. The num- ber of valleys for which the writer has a record is fortj'-three, and the number of terraces in these vallej's is shown in Table IV. The number of valleys with only one or two terraces was really larger than appears from the table; for after the widespread distribution of the terraces had been noticed, valleys where only one or two occurred were not recorded. Table IV. — Terraces. Valleys with — One terrace 3 Two terraces 3 Three terraces 12 Four terraces 8 Five terraces 9 Valleys with — Six terraces 4 Seven terraces 3 Eight terraces o Nine terraces i The terraces are sometimes cut in gravel (fig. 140), and sometimes in rock (fig. 141), but in the latter case there is always a cover of gravel lying over the rock. It may happen in a single valley that the upstream portions of the terraces are almost wholly cut in rock, while the downstream portions are entirely in gravel, as, for instance, along the Kuzzil Su, at the southeast end of Issik Kid. In vallej-s such as those of the Ispairan Su, flowing to Marghilan, and of the Ak Bura, flowing to Osh, it often happens that the terraces are cut for a certain distance in soft strata, or in gravel that fills a basin where soft strata have been excavated, although farther down the stream flows through a narrow canyon in hard strata, without a trace of terracing; l)Ut when the hard strata end and soft ones begin once more, the ter- races are resumed as though the)' had ne\er been interrupted. Another and perhaps the most characteristic feature of the terraces is the per- sistence with which the different members of a series preserv^e the same relati\-e height and width. In terraces due merely to the swinging of the stream from side to side as it cuts steadily downward, one terrace is here or there cut off either at the upper or lower end by another terrace of later date, and a pattern of cusj^s and bays is thus fonned along the valley side. In such cases a single terrace can only be traced a short distance, and the number of terraces is continually changing. In the mountain valleys of Central Turkestan, on the other hand, although it sometimes liapjiens that one terrace truncates another and thus fonns a cusp, this is far from being a prevalent condition ; each le\-el is, as a rule, distinct and does not interfere with its neighbors. Several terraces often nin for many miles side by side without interfering with one another, each one preser\-ing an almost uniform width with remarkable persistency. As a rule, too, the uppermost terrace possesses not only the greatest width, but the greatest height. Such a regular diminution in size can mean only that the cause of the terracing was of steadih- decreasing efficiency. RECONNAISSANCE IN CENTRAL TURKESTAN. 203 TERRACES AS A RESULT OF WARPING. There seem to be but two causes competent to produce terraces of so wide a distribution and so uniform a character. One of these is warping of the earth's crust and the other is change of climate. It is highly probable that terraces resulting from both causes may exist close together, but in the main the terracing in Central Turkestan seems to be due to climatic variations. The reasons for this conclusion are, first, the wide distribution of the terraces, and, second, their relation to the deposition of gravel. Fig. 140. - View down the Kuzzil Su on the eastern border of Bokhara, showing a gravel-filled valley which has been re-excavated. In the foreground four terraces can be seen on the left. A phenomenon of so wide an extent and ot such uniformity in essential features as are the terraces must have a proportionately extensive and uniform cause. It is possible to imagine a complicated and intermittent bending of the earth's crust so extensive and so systematically rel.ited to the streams that all portions of a large area containing four or five distinct and interlocking river basins, with streams flowing in every direction, should be warped so as to cause everv stream to cut terraces of the same .sort and in the same order. But this would involve a more highh- specialized type of bending than is known elsewhere. It would require that 204 EXPLORATIONS IN TURKESTAN, each of the mountain masses, large or small, should be intermittently elevated or that each of the basins should be intermittently depressed in such a way that all the streams should be intermittently accelerated in their work of erosion. This pro- cess involves an alternation of movement and rest from four to six times in each separate drainage area, and at each alternation the amount of uplift and the length of the period of rest nuist have decreased. All this seems improlxible, whatever may be thought of its possibility. ^ It is, however, not only the erosion of the terraces that has to be accounted for; in most cases each terrace in\ol\es an epoch of deposition preceding the epoch of erosion. The gravel deposits in which the terraces are carved occur not onlj- at the mouth of every vallc)- where it opens on the plain, but also along the course of Fig. HI. — Terraces and Meanders of another Kuzzil Su near Chadir Kul. on the Tian Shan Plateau, at an elevation of I 1,000 feet. These terraces are cut partly in gravel and partly in red Tertiary limestone. many streams almost to their heads. Sometimes the gravel lies on rock-cut terraces (fig. 142), where it might have been formed during periods of rest when no uplift was in progress. In other cases, however, the terraces along large portions of the stream course are cut in gravel only, and the rock bottom of the valley is now no deeper than when the first gravel deposits were begun (fig. 143). Where this is tnie the net result of whatever crustal movements have taken place has been that they have balanced one another in such a way as to bring the region back to essentially the same position that it first occupied. There must have been depression to cause the aggradation of the valleys by gravel deposits, and this must have been followed by periodic and decreasing uplifts of which the sum was equal to the total previous depression ; RECONNAISSANCE IN CENTRAL TURKESTAN. 205 nor does this show the full complexity of the problem. In the valley of the Ispairan Su, south of Marghilan, for example, gravels of two and possibly three ages can be detected. The oldest is a very coarse deposit three or four hundred feet thick, which is cemented into solid conglomerate by calcite from the limestone walls. A deep valley was then cut in the conglomerate, so that its remaining portions form a terrace several hundred feet above the stream (fig. 144). This valley was then filled, though to a much less height than before, with gravel of the same sort as the first, except that it is not cemented so firmly into conglomerate. In this second conglomerate another valley has been cut ; and there are places where the filling and cutting seems to have been repeated a third time on a still smaller •-a.'*>S-.»J»'»aA-.v . ■■s%.-M<>ji.-; - Fig. 142. — Terrace wall of the Kan Su, west o( Kashgar, showing horizontal gravel above tilted Mesozoic strata. On the left or north side are the coal measures; on the right are the vermilion-red beds. Between the two can be detected a slight unconformity, A. scale. If all this is due to defonnation it means that there has been an extraordinarily complex series of palpitations — now up, now down — and that while the upward movements ha\-e been parallel over large areas, the downward mo\-ements have occurred erraticall)- here and there in such a way tliat the terraces of valleys close beside one another are of different types, or that the upper part of a valley has merely been cut again and again, while the lower part has been both cut and filled an equal lunnber of times. If, then, the theor}- that the terraces are due to move- ments of the crust can not be said to be absolutely untenable by reason of the coniplicatious that it involves, it certainly matches the facts only indifferently well. 2o6 EXPLORATIONS IN TURKESTAN. XBRRACES AS A RESULT OF CLIMATIC CHANGES. Let us see if the other theory, that of climate changes, is more satisfactory. Starting with a climate and topography similar to those of to-day, what would be the effect of successive epochs of glacial and non-glacial climate or of colder and wanner climate? Judging by what has been found true in other parts of the world, the effect would be just what we find in the terraces of Central Turkestan. During the epochs of colder climate aggradation would take place in all the valleys where the streams had already attained a graded condition ; and that condition would Isoon be established in those valleys where the slope was relatively gentle, Fig. 143.- Terraces of the Kok Kiya, on the Tian Shan Plateau, al an elevation o( I 1,500 (ect. In the foreground and in the middle distance the stream has been caught upon limestone and has cut merely a narrow gorge, while in the gravel between it has excavated a broad flood-plain with terraced sides. though the streams were not previously graded. The graded streams would then swing sidewi.se, and very broad flood-plains wotdd be fonned. When warmer conditions again prevailed the streams would once more begin to cut downward ; the few streams that had already reached grade previous to the period of aggradation would cut into the gravel till a new grade was reached, and then, if time allowed, they would broaden their flood-plains once more. Of the other streams, the majority would soon cut through the gravel coating of their flood-plains and intrench themselves in the solid rock beneath. If another cold epoch ensued, the previonsl}- graded streams would begin to aggrade and would fill their valleys in the same way as before ; the others would become graded and would open their valleys and fonn flood-plains once more. Thus, In- a succession of alternations between RECONNAISSANCE IN CENTRAL TURKESTAN. 207 colder and wanner epochs, a series of terraces would be formed closely resembling those found to-day, provided only that the epochs constantly diminished in intensity and duration. Those streams in which a graded condition had been reached before this series of climatic changes began would have their terraces cut entirely in gravel, while the others would have terraces composed partly of gravel and partly of rock. The streams of this class are as a rule deepening rather than widening their valleys. It is noteworthy that this series of climatic changes corresponds essentially with the series inferred from the old moraines, and the agreement of the two greatly favors the tlieorj' that accounts for both. In this connection two points need emphasis. In the first place, it has been shown that the moraines give e\idence of interglacial epochs alternating with glacial epochs rather than of a single glacial A— limestone. B, C, D— successive fillings of gravel. Fig. 144. — Cross-section of the Ispairan Valley, showing successive periods of cutting and filling. period which came to an end with a series of partial glacial retreats separated by intervals of glacial rest. The terraces show even stronger evidence of the same conclusion. The deposition of gravel and broadening flood-plains on the one hand and the cutting of narrow trench-like valleys on the other do not represent successive stages of the same kind of climate change ; they represent contrasted climatic conditions — namely, the systematic alternation of colder and wanner climates. In the second place, the terraces decrease in width, height, and preser\^ation in the same wa)- that the moraines decrease in size and in the degree of weathering and erosion to which they have been subjected. In both cases the oldest examples are large and well developed, but not ven,- well preserved ; the others are successively smaller and better preserved. All these points of agreement increase the proba- bility that the theory of a glacial period consisting of interglacial epochs is correct. One difficulty presents itself — the number of terraces and of moraines does not always agree — the maximum of the one is nine, of the other only five. Part of this discrepancy is due, as has been already explained, to the fact that some of the terrace series are complicated by one or two minor terraces, which seem to be due merely to ordinan- swinging of the streams; but even with due allowance for this complication, there seems to be some evidence of a sixth unexplained terrace. It may therefore be suggested that the first of our glacial epochs was not actually the first, but merely the maximum, and was preceded by others which have left no trace save in doubtful terraces. This, however, is at present pure conjecture. 208 EXPLORATIONS IN TURKESTAN. One of the most important points in a further stndy of the climatic changes of Turkestan is to establish the correlation between individual moraines of known epoch and individual terraces. This seems to be possible, for in man)- cases the moraines themselves are terraced, while elsewhere, as in the valleys of the Kara Kul Su and Mudinim Su, moraines have been deposited upon terraces. One of the most promisin- weather the whole lake is a mere sheet of salt on which one can walk, although with some danger of breaking through. In the latter event one finds pure salt as deep as to the knee and then half-liquid nuick. The salt is collected by the people and is carried as far as Kashgar. It is used just as it occurs, without cleansing. Fig. 145. — Shor Kul, looking south. A smooth plain about 40 miles long and 10 miles wide surrounds the lake. Much of it is so level that it forms a sort of swamp with a thick growth of tamarisks and tall sword-edged marsh-grass. The surface of the swamp is dr}', except in rainy weather, although in many places there is a bog below the dr\- surface cnist. The material of the plain is everywhere a fine silt of lacustrine origin and full of salt. Toward the edges, where the plain begins to rise, the swamji gradually gi\-es place to a desert. Still nearer to the mountains a deposit of rough gravel is encroaching on the fine lake deposit. The gravel is the front of a large number of broad, flat fans which drown the foot of the naked mountains and have converted some of the lower spurs into islands. Usually the ascent from the lake to the mountains across the belts of swamp, dt}' lake deposit, and gravel fonns a smooth 2IO EXPLORATIONS IN TURKESTAN. curve without a trace of terracing or any indication of old lake shorelines. Here and there, however, the smooth stretches of the swamp are broken b}' low, rounded hills or by broad, flat tables, 20 to 40 feet high and several miles wide, which are distinguished by a sparse growth of knotted poplar trees. On the soft slopes of these elevations are found most of the springs that make it possible for the poor Kirghiz to inhabit the wretched swamp. Jai Tebeh (Devil Hill), at tlie western end of the lake, is one of the best examples. Here on the sides of a small rounded hill five small springs bubble gently up at heights of from 10 to 40 feet above the green swamp which stretches for 3 or 4 miles on every side. The material of the hill and of the swamp seems to be identical, although possibly that of the hill is a little more sandy. In neither is there the least sign of gravel. A few miles west of Jai Tebeh a fonnation of apparently the same sort as tliat of the hill assumes the shape which has above been called a table, although it might better be described as a low and xer}' broad promontor}'. It rises from the swamp as a rude terrace with an irregularly dissected front, on which there is a suggestion of smaller terraces. Near the borders the top is somewhat rough, but it soon becomes very even and stretches back smoothly toward the mountains, near the base of which it merges into the slope that rises more steepl)', although still ver}^ gently, toward the mountains from the edge of the adjacent swamp. On this low promontory- are two or three springs like those of Jai Tebeh. A few miles farther to the west, at Dongjigdeh, another hill stands in the middle of the portion of the swampy plain lying west of the lake. The hill is about 40 feet high and has a spring near the top. Like Jai Tebeh, it appears to be mostly made of silt, but there are gravel and some sand scattered here and there. Six other streams were seen in different parts of the basin, welling up on small hills at a height of from 20 to 30 feet above the surrounding swamp or neighboring lake. In all the springs the water was sweet, and the material from which they flowed was the same silt as that of the swamp, so far as the eye could detect. It seems hardly possible, however, that the underlying j^art of these hills can be composed of this same silt. The one hill where sand and gravel occur seems to furnish the key to their structure, and the suggestion afforded b}- this one is borne out by evidence which will be presented after the statement of the conclusion to which it leads. Shor Kul appears to have been twice expanded to a size much greater than that of to-day. At the first of these expansions it reached a height of about 350 feet above the present water level. It then retired, so that the lake deposits were first covered with sand and gravel and later were well dissected. It next rose again, although to a less extent, and covered some of the remnants of the old lake deposits with a new layer of silt (fig. 146). The remnants of the old deposits are the hills and tables which have already been described, and which are now left exposed by a second retreat. The springs occur on them because the layer of sand and gra\-el on top of the earlier lake beds is easily pervious to water, while the silts above and below are impervious. Consequently water from the base of the mountain beyond the end of the silts gathers in the sand or gravel and percolates gently downward toward the lake. In the little hills the upper layer RECONNAISSANCE IN CENTRAL TURKESTAN. 211 of silt is thinner than elsewhere and has often been broken through by erosion. According-ly at these points the water finds a ready exit and bubbles upward because it is under pressure. It is, however, possible that the deposits of which the hills are the remnants may belong to an earlier time than that mentioned above. This point and others had to be left unsettled on account of the short time allowed for the writer's journe\- and of the peculiarh- unfavorable conditions of xniseasonable rain and mud experienced at Shor Kul. Let us now turn to the more direct evidence of the double rise of the lake. During the first expansion, when the lake reached its maximum size, the water seems to have stood about 350 feet above the present level. On the north side of the plain, a little below this height, there is a sudden transition from coarse, angular gravel to the finest silt without a trace of pebbles. The gravel is subaerial waste of the normal type for an arid mountain region, and is now being slowly pushed forward over the silt. The silt could hardly have been deposited an^-where except iu a lake, for under almost any conditions of climate some gravel would be included in a deposit so close to the base of the mountains, unless it was laid down a little offshore in standing water. At the west end of the plain, southwest of Kirk Bulak, there is at the same 350-foot level a small bench and cliff, cut for about half a mile in the silty grav'el which there cloaks the mountain flanks. At the opposite end, near Pchan, a large compound fan of gravel has cloaked the lake silts smoothly as high as 130 feet above the present lake level ; but at an ele\ation nearly 400 feet from the water the gravel has a different fonn. At the lower le\el the gravel cloak is spread smoothh- and the streams wander across it in numerous shallow and e\-er- changing channels. Above a height of 400 feet the gravel is well dissected, and each stream has a single, definite terraced valley. On the south side of the lake the plain rises more rapidly and the old lacustrine deposits are considerably dissected, perhaps because of a slight warping. Never- theless there are the same lacustrine silts and subaerial gravels as on the north side, and the silts end at about the same height, that is, a little over 350 feet above the lake. Elsewhere old lake silts are found up to a height of 200 or 300 feet abo\e the water, where they begin to be covered with gra\el. It seems quite clear that the lake once stood 300 or 400 feet higher than to-day. At a place called Dungsugot,* on the .south side of the plain, 4 or 5 miles from the western end of the lake, there is good evidence of a second rise of the lake separated from the first rise by a period when the water retreated nearly or quite to the present level. Here the older lake deposit is considerably dissected (fig. 148), probably because the slope of its surface is much stee{)er than elsewhere. The valleys car\-ed in the deposits show three terraces which extend out to the fronts of the spurs, and even around them, from valley to valley. The spurs are flat-topped and for the most part are made of lacustrine silt. On the top, however, is a layer of gravel only a few inches thick at first, but gradually increasing in *Tlierc is a spring at Dungsugot where a camp could be made from whicli the terraces and lake deposits could be minutely studied. Fodder for horses would probably have to be brought from one of the villages 6 or 8 miles away. 212 EXPLORATIONS IN TURKESTAN. thickness toward the inouiitains. The gravel extends down the slopes of the terraces (fig. 146), but at the bottom it is abruptly covered by another deposit of lacustrine silt. On the latter there is nowhere any gravel except in places where it is now creeping down from the terraces, or where a stream comes out from the mountains and is now covering its broad flood-plain with a thin coating of pebbles. A=bed-rock. B=lake silt of 350-foot level. C=first terrace and layer of gravel coveriug silt. D=second terrace. E=third terrace. F=liill with springs. G=lake silt of 100-foot level. H^lake. I=edge of mountains. Fig. 146. — North and south section of the plain of Shor Kul from the lake lo the mountains at Dungsugot, In the valleys the lower terraces are not cut in silt, as is the case on the fronts of the spurs toward the lake, but in gravel deposited in the valley after it had been cut below its present depth (fig. 147). The reader will at once perceive that fig. 147 is almost identical with the cross-section of the Ispairan Valley (fig. 144), and will doubtless infer, as the writer does, that both are the effect of a similar series of climatic changes. Fig. 147. — Cross-section of a Valley cut in the silt at Dungsugot. For explanation see fig. 146. mh All the phenomena of Shor Kul are satisfactorily accounted for by the same theory- which explains the old moraines and the terraces. The earliest record of the lake was at the stage of greatest expansion ; the silts of the 350-foot level were then laid down. Later the climatic conditions changed, so that the lake shrunk almost, if not quite, to its present size. Gravel at once began to creep forward over the silt, and, as the surface was very smooth, the streams wandered widely and covered the whole lacustrine plain with a layer of pebbles. In time, however, the amount of waste from the mountains grew less under the influence of the changed RECONNAISSANCE IN CENTRAL TURKESTAN. 213 climate. The load of the streams was correspondingly decreased, and they cut downward nntil the relief was like that which is represented by the outer valley cut in the silt (B, fig. 147). At the same time the front of the old silts was being gnawed back and the slope was being prepared on which the terraces (fig. 146) were later cut. The surface of the old lake deposit must originally have presented an unbroken slope (I H in fig. 146). The bed of the stream, the lower dotted line, I B H, must have presented an equally smooth although more concave slope. The two must ha\e met at the lake shore when the water was at its lowest level. Even the most cursory inspection of the valleys and spurs shows that this point of meet- ing must have been far out in the swamp close to the present shoreline. Therefore the lake must have been small and shallow, and the climate must have been similar to that of to-day or possibly even drier. Fig. 148. — The gravel-covered lacustrine deposits at Dungsugot, illustrating the same features as the preceding diagrams. For explanation see fig. 146. The next changes were those recorded in the terraces and in the graxel which fills the valleys represented in fig. 147. It is easy to infer that the lake must have risen and fallen twice, and that each rise was associated with the fonnation of a terrace and with the partial filling of the valleys with gravel, but of this we have as yet no direct evidence. The ne.xt rise of the lake of which we have positive proof was probably also the last. It deposited the recent silts (G, figs. 146 and 148), which rise to a height of 100 feet and bur)- not only the foot of the tenaces, but also the isolated hills on which well up the springs of sweet water in the midst of the salt swamp. Now a last change of climate has again reduced the lake to verj- small proportions. 214 EXPLORATIONS IN TURKESTAN. Although we do not find in the historj' of Shor Kul a complete series of records to match all the changes of climate inferred from the stud\- of the old moraines, we find no records inconsistent with such changes and many confinnator)- of them. The essential features of our glacial theorj- are that a number of cold or glacial epochs were separated by wanner interglacial epochs, when the climate was approxi- mately like that of to-day, and that these epochs decreased in severity and length from fust to last. The retreat of the lake between the two epochs of unequal expansion supports this most clearly. Further study will probably show that the past oscillations of the lake agree even more perfectly with those of the glaciers. .\t present only a tentative correlation of lacustrine and glacial epochs is possible. The silts of the upper lake level may represent either or l:)oth of the first two glacial epochs ; the cutting of the deepest valle}- in them represents the succeeding wanner interglacial epoch ; the third and fourth epochs, glacial and interglacial, are perhaps represented by the gravel filling and the terraces, respectively, which lie in the deep valley. The fifth glacial epoch seems to correspond to the rise of the lake to the lOO-foot level, and the present retreat of the ice to the present retreat of the water. SUMMARY. In our review of the history of Central Turkestan, from Paleozoic times down to the present, we have found that the greater changes ha\-e on the whole affected the entire country rather than small areas. Uniformity has been the rule. During the Paleozoic era the entire region was submerged beneath the sea and the deposi- tion of calcareous strata was long-continued. After the latter had attained a great thickness tectonic movements began on a large scale and continued until the lime- stones had been closely folded and mountains had been fonned, which were worn away during the first part of the succeeding era. The Mesozoic and Tertiary eras are not sharply separated and must be considered together. Throughout the greater part of these eras tenestrial conditions prevailed, with the deposition of strata characteristic of interior basins, namely, conglomerates, cross-bedded sandstones, and silts, which appear to be vast playa deposits. Most of the strata are without fossils, and in this and other ways suggest that the climate was dr)- and that desert conditions prevailed more or less extensively. Only once during this long period did the sea encroach on the land. This was at the end of the Mesozoic era, when limestones and marls were laid down in what seems to have been a sea of somewhat fluctuating depth. It is not impossible that between the Mesozoic and Tertiary eras there were world-wide movements which elsewhere caused uplift and erosion, followed by unconfonnable deposition ; but here the movements of this time caused encroachment of the sea and deposition. In the basin region of America the Mesozoic and Tertiary eras present a succession of strata notably similar to those of Central Asia. The resemblance is so marked and extends so far into details that it can scarcely be the result of chance. It suggests that interior arid basins which to' era erosion and deposition had so far lowered the mountains and filled the basins that the countr>' was in a stage of late maturity or even of old age. Considerable warping had taken place during the preceding period, and perhaps was still going on, but the rate was so slow that even the languid erosion of late maturity was able to keep pace with it. At the beginning of the Quaternary era, however, there was a revival of internal activity which manifested itself chiefly along the lines of movement of earlier times. Warping and .some faulting then took place so rapidly and so recently that the forms to which they gave rise still dominate the topography, and the effects of erosion are chiefly noticeable in the young valleys. By these movements Central Turkestan was divided into its present physiographic provinces. One province, the Tian Shan plateau, is essentially a broad, flattened arch, on the top of which a number of minor warpings give rise to lofty plateau-like ridges surrounding elevated basins. A second province, the Alai Mountains, is a similar arch, except that it is narrower and lacks the minor comigations on the top. Both of these provinces are char- acterized by very precipitous young valleys, between which are tilted and well- preserved portions of the Tertiary penepJain. The two other provinces are basins, those of Kashgar and Fergana, the flat floors of which have for ages been regions of deposition. In the Fergana basin deposition has for the present ceased, but in the Kashgar basin it is still progressing actively. The recent geological history of Central Asia has been controlled b\- a series of climatic oscillations between conditions of relative warmth to those of relative frigidity. Evidence of these changes is found in phenomena of three distinct types associated with the headwaters, the tnmks, and the lower ends of the rivers. In the high mountains many headwater streams flow from glaciers which in ancient times were much expanded so as to deposit moraines at considerable distances down the valleys. The moraines show that the ice advanced five times during as many glacial epochs, and that between the advances there were epochs of retreat which must have been almost as warm as the present, if not wanner. The moraines further/ show that the glacial epochs steadily decreased in intensity- from first to last, and, although less clearly, that the interglacial epochs correspondingly decreased in length. Along'their middle course the streams, almost without exception, flow in terraced valleys. The only adequate explanation for these seems to be a series of decreasing climatic oscillations from cold epochs on the one hand, when increased weathering overloaded the streams and caused them to aggrade and broaden their \alleys, to warm epochs on the other hand, when the streams cut narrow canyons in the bottoms of the previously formed flood-jilains, thus jiroducing terraces. The number of the terraces does not agree precisely with the number of the old moraines, but the disagreement is easily explicable by a simple expansion of tlie theory of climatic changes so that it shall include a series of increasingly severe glacial epochs preceding the epochs of the decreasing series. In other respects the agreement of the terraces and the moraines seems \-er\' close. The fonner as \\cll as the latter indicate not only that there were oscillations from one extreme of climate to the other, but lliat in intensity as well as in length each succeeding period was less than its predecessor, for the terraces decrease steadily in breadth and 2l6 EXPLORATIONS IN TURKESTAN. heif^lit. Where lakes are found at the lower euds of rivers, they show changes of level that are only explicable on the theory of climatic oscillations of decreasing intensity. Only two of these have been clearly identified, but there is some indi- cation of a lar<,'er munber, and it is entirely possible that further obser\-ation will show that the lakes clianged as often as the glaciers and the rivers. When the glaciers advanced and built their moraines, the rivers swung laterally, aggrading and broadening their valleys, and the lakes expanded and spread their silts. When the glaciers retired the streams cut gorges and the lakes contracted. The es.sential point in our study of the recent geological histor)' of Turkestan is this : From three separate lines of reasoning, based on the allied yet distinct phenomena of glaciation, terracing, and lake expansion, we arrive at the same con- clusion, namely, that during the Quaternary- era there have been a number of colder or glacial epochs, five or more, separated by wanner interglacial epochs when the climate was similar to that of to-day ; and further, that these epochs progressively decreased in length and intensity. When a single theory- fits all the facts of a single series of phenomena, it becomes probable; when it fits the facts of three distinct series of phenomena, it becomes highly probable ; and when it fits the facts of several continent';, it becomes in a ver^' high degree probable. Much confidence is therefore felt in the theon,- above announced. It is yet to be applied to the basins of the Caspian and Aral seas on the west. A most interesting additional step would be to see if the theory is capable of explaining the great basin deposits of Central Asia which lie to the east of the region here described. TURKESTAN Route ofihe aitlhor MAP OP^ IRAN' SCALE OF MILES o The Basin of Eastern Persia and Sistan. By ELLSWORTH HUNTINGTON, Carnegie Research Assistant. 217 The Basin of Eastern Persia and Sistan. By Ellsworth Huntington, Carnegie Research Assistant. INTRODUCTION. At the beginning of the work of our expedition in Central Asia it became evident that the problem of the plnsical changes which ha\-e taken place in the Caspian basin since the advent of man is so complicated as to require the work of many years for its solution. It also became evident that if the historj- of the chief changes could be ascertained in smaller neighboring basins where there was reason to suppose that a similar series of events has taken place, the elucidation of the Caspian problem would be greatly facilitated. Accordingly, during the summer of 1903 our attention was turned to Issik Kul and the mountains of Turkestan; and later, on the approach of winter, I was dispatched southward to the renrarkable basin of Sistan, in Eastern Persia. Not onh- the basin, but the countn,- traversed in reaching it, proved to be full of e\idences of very recent changes in physical condi- tions, and the time-scale established by their means is applicable in a large degree to the Caspian region, for the main line of evidence, the terraced character of mountain valleys, is found abundantly in both the Sistan and Caspian basins. The records of antiquity and the work of previous explorers make it certain that both basins have long been inhabited and that their present sparsely populated condition is essentially different from that of the past. The question to be answered is whether this condition is due to purely human causes, such as the deca\- of races wars, famine, deforestation, and the exhaustion of the soil by prolonged culti\ation on the one hand, or whether it is due to physical causes, such as changes of climate, the warping of the earth's crust into higher mountains and deeper basins, the natural changes of the course and volume of rivers, and the encroachment of sand-dunes on the other. Before this can be answered the human histor\- of the countn,- must be more carefully elucidated by archeological work and the physical history by geographic work. In the pursuit of the latter object, under the direction of Professor Davis, the problem resolved itself into two parts, namely, the physical historj- of Central Asia in recent times as influenced by internal or terrestrial causes, such as the warping of mountains and the deepening of basins, and the histor}- as influenced by external causes, such as changes of climate. The studies of a year and a half have led me to think that while numerous crustal movements furnish al)undant e\idences of the earth's internal activity during ver>- recent geological times, most of the movements are too ancient to be connected with human history and too local to have produced 219 220 THE BASIN OF EASTERN PERSIA AND SISTAN. nniforni changes over broad areas. Nevertheless, the purpose of our expedition can not be achieved until we possess such a knowledge of the movements of tlie earth's crust in Asia during recent geological times as shall enable us with certainty to estimate their possible effect upon early man. I have therefore recorded all the data on this subject which came under my observation. Moreover, as my journey led through an unknown country, I have thought it advi.sable to record certain geological facts relating to earlier times. In Asia, as in liurope and North America, the main events of that part of recent geological time which immediately precedes and includes early man seem to have been due to changes of climate. Evidences of this are found abundantly in Persia, Transcaspia, and Turkestan. It is therefore of first importance to ascer- tain the exact sequence and degree of each change and the dates of the later changes in relation to the origin of man, and accordingly the main jjortion of this rejMrt is concerned with the evidences of climatic change in Persia, and with an attempt to fonn a tentative scheme of the physical history- of the countr>' during Quaternary times. The influence of climate, and especially the physiographic results of climatic changes in nonglaciated regions, are so little known that it has seemed necessary- to devote some attention to a theoretical examination of these questions. Accordingly this report is in the main a study of the influence of climate and of climatic change in Persia. When this influence is understood, and when the sequence of events shall have been clearly made out, we shall be in a position to determine the relation of physiography to climate in Persia and to apply our results to the larger problem of Western and Central Asia. ROUTE. Between the high mountains of Central Afghanistan on the east and the fearful salt wastes of Eastern Persia on the west lies a dreary region of naked mountain range, huge fans of rough gravel, and level basins floored with fine silt. At the northern end of this region the Heri Rud, the river of Herat, furnishes life to the towns and villages of Herat, Serakhs, and Tejen, while to the south the half-mythical Helmund, before losing itself in the immense swamp of the Hamun-i-Sistan, sup- ports the inimerous villages of the province of Sistan. Between these two rivers the lowlands are absolute deserts, while the uplands above an altitude of 4,000 feet are sparsely studded with villages located at the bases of the higher mountains, where water can be procured. Across this inhospitable region lies the route from Transcaspia to Sistan. (See map.) Through the courtesy of General Ussakovsky, governor of the Russian pro\ince of Transcaspia, to whom our expedition is indebted for many favors, I was allowed to follow the Russo-Persian frontier and to stop at militar>- posts to which foreigners are not usually given access. Starting from Askhabad, the capital of Transcaspia, November 23, 1903, 1 proceeded eastward along the southern border of the province to Serakhs, at the northeastern corner of Persia. There I was joined by Mr. V. G. Yanchevetzki, secretary for special affairs to the governor of Transcaspia, and the rest of the journey was made in his company. To him, in ROUTE. 22 1 large measure, is due the success of our three months' journey in a couutr}- where travel is not only difficult, but sometimes dangerous. His presence was especially acceptable because of his unfailing good humor under trying circumstances and his kindness in conforming his plans to the whims of a geographer. Leaving Serakhs December 4, we crossed into Persia and spent the next month, till January- i, in tra\-eling as nearly as possible straight southward along the Afghan-Persian boundar\', past the playa of Khaf to the oasis and swamp of Sistan. At the latter place we remained till February 5, raitch of the time as the guests of Dr. .\. J. Miller, the Russian consul, to whom my heartiest thanks are due. Not onlj- did he entertain us most hospitabh-, but through his help it was possible to see in a short time the most important parts of the interesting region of Sistan. From the Russian consulate as a center, trips of from four to eleven days' length were made in all directions. During a part of our stay in Sistan I was the guest of the British officers connected with the Sistan Arbitration Commission, and the time so spent was as valuable scientifically as it was pleasant socially. In spite of his pressing political and military duties. Col. G. H. McMahon, the British commissioner who is settling the disputed boundan,- between Persia and Afghanistan, finds time for an enthusiastic study of the ph\siography of the new region to which his work brings him. To him and to his assistants, Mr. G. P. Tate, topographer, and Mr. T. R. J. Ward, irrigation officer, I am indebted for information and suggestions of the greatest value, to which I shall ha\e occasion to refer later. Our return journey from Sistan to Transcaspia lasted from Februar}^ 5 to March 13. It was made in a northwesterly direction, by way of Birjand, Tun, Turbat-i-Haideri, and Meshed, to Askhabad. Ever>-where we received the most hearty hospitality and read\- help from both Briti.sh and Russian consular officials, to all of whom thanks are due. LITERATURE. Few travelers have penetrated eastern Persia, partly because of its remoteness and parth- because it offers few attractions in the way of scenerj-, historic cities, game for the hunter, or people with picturesque dress and manners. Most of the foreigners who traverse the country- are bound on business, usually official, and follow the easiest and most frequented route through the mountains, where villages are numerous. This route, which leads from Meshed, by way of Birjand or Khaf, to Sistan, is, indeed, the only important road that leads far south in Eastern Persia. Other routes have been followed chiefly by British officers who were studving the country from a military- point of view either as surveyors or consuls, or as members of the various bonndan- commissions whose thankless task has been the demarca- tion of the boundaries of Persia, Afghanistan, and Baluchistan. These officers and a few \enturesome travelers have written almost the only accounts of Eastern Persia which we possess. The majorit\- of the accounts are geographic in the sense that they describe the country and people with great accuracy of detail, but all of them fall short of the modern geographic ideal in that they contiiin little save empirical accounts of isolated facts encountered along the line of the author's route without reference to any underlying scheme of geographic classification. The best of these 222 THE BASIN OF EASTERN PERSIA AND SISTAN. books, and also the most recent, is that of Major Sykes, "Ten Thousand Miles in Persia," a work which embodies a vast amount of careful observation and record, supplemented by most painstaking research. To it and to others of the same class which are noted in the bibliography at the end of this report, I shall have more or less occasion to refer. Lord Curzon's " Persia " stands easily first among books on the country as a whole, but unfortunately it deals but briefly with the eastern part of the Shah's dominion, and hence will be referred to but little. Of books by pro- fessional geographers or geologists, there is, so far as I know, not one which deals with, Sistan and the most important parts of Eastern Persia. Hlanford, liowever, over thirty years ago, traversed the neighboring regions to the south and west, and has given ns the result of his observations and studies in a valuable review of the geology of Persia as a whole, and in a masterly essay on that most striking of Persian physiographic phenomena, the huge gravel fans at the base of the mountains. More recently Vredenburg has written a geological account of the portions of Balu- chistan to the south and east of Sistan. His facts are valualjle, althougli some of liis conclusions are open to question. In addition to the classes of books already named there are several accounts of Eastern Persia wliich are mere travelers' tales of the most ephemeral interest. The books of all classes, so far as I have consulted them, are mentioned in the bibliography at the end of this report, although not all are referred to in the text. As an aid to future students a brief comment on the nature of the work is appended to each title in tlie bibliography. OUTLINE OF THE FOLLOWING REPORT. Eastern Persia is one of the most desolate lands in the world. The chief cause of its desolation is aridity, due in the first place to the countr>-'s continental position and in the second to its basin character. As a result of Persia's continental position the prevailing northwest winds which blow across it have not only alread)- traversed witle stretches of land and been deprived of most of their moisture, l:)ut the)- are con- tinually advancing into more heated regions and thus becoming wanner and less ready to part with moisture. The basin character of the country tends to increase the dryness of the interior ; for the mountains which snn"onnd the basin are for the most part lofty and cau.se the precipitation of whatever moisture the winds may still contain after their long journey from the sea, so that almo.st nothing is left for the inner regions. Eastern Persia, northwestern Baluchi.stan, and southwestern Afghanistan are all included in the basin which has just been mentioned. Close to the eastern border of Persia this basin of Iran, as it is called, is divided into two snl)sidiary basins by a range of mountains running north and south. (See sketch map, fig. 152.) East of the range, and complementar)' to it, lies a remarkable dejires- sion containing the Heri Rud River and four large hollows containing playas or saline swamps. (See map at end of volume.) Although the geological history of the countr}' is imperfectly known, the unconformability between Tertiary- deposits of continental or estuarine origin and Cretaceous deposits of marine origin shows that Iran began to assume its present basin form far back in the Tertiary era. Since OUTLINE OF THE REPORT. 223 that time minor l)asiiis have been produced within the greater basins. Throughout the Tertiary era and perhaps even during Quaternary times the basins ha\-e been the receptacle of the waste from the mountains, which has now deeph- filled their lower portions. The waste thus deposited lies horizontal in the centers of the basins, but is warped along the edges, the older strata being more warped than the younger. Apparently the basins have been subjected to a gradual process of intensification by which they have become deeper, while their edges have been folded and uplifted. The large basin of Iran, with its rim of lofty mountains, is a typical example of long-continued erosion and deposition in a mountainous plateau under arid conditions. The traveler is wearied by an endless repetition of naked mountains vising on the edges, or even in the midst of smoothly-floored basins, in which the streams have for ages deposited waste from the mountains. In the centers of many basins stretch vast playas, whose smooth expanse is often covered with salt. Where water is more scarce fields of drifting sand move slowly forward, while between the barren mountains and the plains gently sloping fans of gravel merge into level sand and silt on the one hand, while on the other they mantle the flanks of the ridges, and even overtop the pa.sses, uniting one basin to another. What few streams there are flow toward the basin centers in terraced valleys, and often the shores of the playas and lakes are also terraced. No one, however unobservant, can fail to be struck by the contrast between the physical features of Persia and those of the well-watered countries of Europe and America. The only competent cause for this difference seems to be that the climate in the two regions is different. It is often assumed that the presence of inclosed basins, such as those of Persia, is due to some special variety of warping of the earth's crust. That the basins are due to warping can hardly be doubted, but there seems to be no reason for thinking that the warping is of a peculiar sort. The mountain building of the Al])s and the Himalayas must have given rise to basins just as did the mountain-building of Persia and of the basin region of North America. The present diflerences are due to differences in climate. In the Alps one of two things happened : First, the streams may have eroded so fast that when tectonic forces began to uplift the mountains and fonn basins, erosion kept pace with the uplift, and the streams which crossed the rims of the basins pre- served uninterrupted channels from the interior to the e.xterior. Second, a newly formed basin may have been filled by a lake, the overflow of which soon cut a channel so deep as to drain off all the water, or at least all that stood at anv great elevation above sea-level. In either case the basins were quickly converted into valleys opening freely toward the sea. In Persia, where the climate is dr>-, on the contrar}', the erosion of the scanty streams was insufficient to keep pace with the movements of warping, and inclosed basins were produced in which the streams still terminate in salt lakes, playas, or gravel fans, where all the material that comes from the mountains is preser\-ed. A peculiar topography was produced, which consists of inclosed basins within which are huge gravel slopes, broad plains of silt, buried mountains, .salt lakes, and fields of sand-dunes. In brief, basins are the universal accompaniment of mountain-building, but their preser\-ation is dependent on a dry climate. Such a climate, it is tnie, is often due in large 224 THE BASIN OF EASTERN PERSIA AND SISTAN. meastire to the presence of mountain barriers which shut out the moisture-laden air of the oceans from the basins which they inclose. Thus the fonnation of basins tends to produce a dn>- climate, and the dr}- climate tends to preser\'e the basins and at the same time to produce a peculiar topography. It is not simply with aridil)- of climate that we have to deal in Eastern Persia. During Quaternary times there appear to have been changes of climate, and as some of the changes took place ver)- recently, probably since the occupation of the countrj' by man, their careful study is of great importance for the purpose of our expedition The chief evidences of climatic changes take the form of numerous lacustrine and fluviatile terraces. The former, like the terraces of Lake Bonneville, are due to changes in the water-level of lakes or playas, while the flu\'iatile terraces appear to have been fonned where one type of climate caused the deposition of gravel, and another t)'pe, probably either drier or wanner, caused this to be channeled. The physiographic effect of changes of climate is so important that its exemplification in Persia demands the most careful consideration. The uniformity of the terrace phenomena throughout the semi-arid countries of the western half of Asia seems to be explicable only on the theory of a succession of epochs of changing climate corresponding to the glacial epochs of more northern countries. The lake and district of Sistan afford unusually clear evidence as to the sub- division of Quaternary' time. During the latter part of the Quaternary era volcanoes broke out within the area of the lake, and in the course of their eruptions large portions of the lake bottom were uplifted and covered in part with caps of lava- Subsequent erosion has produced cliffs from 50 to 600 feet high, which expose large ])ortions of the ancient lake deposits. The histor}' of the Quaternan,- era and of the forms assumed in Persia by the period which corresponds to the glacial period of other lands is here laid bare without the concealment of earlier phases and without inidue emphasis on later events. The record of the climatic changes of the QuaternarA^ era is almost ever^^'here incomplete, whether pre.ser\'ed in moraines, in terraces, or in aqueous deposits. One fonnation is placed upon another, and unless each successive epoch happens to be less severe than its predecessor, the traces of earlier epochs are almost sure to be effaced. The records of climatic change are preser\-ed most perfectly in the bottoms of shallow lakes without outlets, where a diminution in rainfall or an increase in evaporation produces a great diminution in the size of the body of water and con- sequently in the character of the .sediments deposited. Naturally the bottoms of such lakes are of little use to the geologist, because of his inability to stud)- them. Hence the importance of Sistan, where so large a part of the record is exposed. It affords a key which may serve to inilock the history- of the neighboring Caspian basin and of still larger regions. The deposits uplifted at the time of the Sistan volcanoes and exposed to view by the erosion of the lake consist of layers of reddish clayey silt varied with bands of sand and gravel on the one hand, systematically alternating with remarkably uniform unbroken layers of hard, greenish claj- on the other. The reddish lajers contain lateral unconfonnities, discontinuous layers of coarser material and rain- drop prints, which indicate that they are of subaerial origin and were laid down by PIIYSIOGKAPIIV OF EASTERN PERSIA. 225 ninninjT^ water or in playas when the lake floor was almost free from pennanent water, and hence during epochs of aridity. The green clays on the other hand are so fine-grained and uniform in texture and so free from changes of stnicture that they appear to be lacustrine deposits, laid down at a time when the lake was full of water, and hence during epochs of more abundant moisture. The entire formation of alternating reddish and green strata is most satisfactorily explained on the theon.- that it is the product of a series of climatic oscillations during which the lake was first dry and then full. The histor\- of the region after the volcanic erup- tions is recorded in gravel deposits which overlie the strata just described and alternate with fine gravel and in terraces which dissect all the strata. The gravels and terraces appear to indicate a continuation of the climatic oscillation down to ver)- recent times. The total number of oscillations amounts to fourteen or fifteen, and ma)' ha\"e been more. As one ascends from the bottom to the top of the deposits, the greenish layers iucrea.se in frequency and to a less extent in thickness up to a certain point, while the red layers become correspondingly thinner. After the green beds have reached their maximum development there is again a decrease in thickness which can be traced only through a few stages because the clays soon give place to gravels. The thickness of the layers is probably proportional to the length of time consumed in their accumulation. Therefore where the red laj-ers are thin, epochs of desiccation must have been short, and epochs of lake expansion must have prevailed for rela- tively long periods. Where the red layers are thick, on the contrary-, the epochs of desiccation must ha\e been longer and more important, and those of lake expansion must have been short. The meaning of the clays, the overlying gravels, and the terraces seems to be that the Ouaternar}- era in Persia consisted of a long series of increasingly strong climatic oscillations, followed by a nearly equal series of decrcas- ingly strong oscillations. The latter appear to correspond to the series of oscillations which we know as the glacial period in more northern countries. Furthermore, there is evidence, based on phjsiographic, archeological, and historical observations, which indicates that the last of the climatic oscillations may have been in progress during historical times. THE PHYSIOGRAPHY OF EASTERN PERSIA. Eastern Persia is a land of gra\el and nakedness, of huge desert basins and desolate, interminable slopes, of tantalizing mirages and bare mountains. Springs and fountains are things to dream of except directly among the mountains, and the traveler and his tired animals must be content with the brackish water of rare wells or the ]ioor brine of an ever-diminishing salt stream. Day after day one sees the same sad monotony of parched plains and lifeless mountains. At long intervals nomads pitch their black tents beside wretched wells and feed their sheep and camels on the sparse brown grass which springs up for a brief month at the end ot winter. The mountains are naked masses of rough, jagged rock, rising as islands in the midst of their own waste. Drought and aridity are ever\-where written large in the dearth of vegetation and in the verj- fonns that the earth itself 226 THE BASIN OF EASTERN PERSIA AND SISTAN. assumes. Tlie whole country is sad and desolate — a region to be shunned b)- those who have dwelt in a happier land. "So far as the surface of the Persian plateau has been surveyed," wrote Blanford, thirty years ago, "it consists of a niunber of isolated plains of varying extent and elevation above the sea, all without an)- outlet, and separated from each other by ranges of hills, frequently of consideral)le height. The lowest portion of each of these plains is generally a salt lake or marsh. If there be a lake its level often fluctuates, and one or two seasons of deficient rainfall suffice to lay bare the greater portion of its bed, or to convert it into a marsh. Rivers are few in number and singiilarly small in volume; in fact, not the least striking feature of the country consists in their paucity or absence. The whole of Persia, except near the shores of the Caspian and on the western slopes of the Zagros, is, in fact, a desert, and all cultivated oases owe their fertilit)- to irrigation from springs or from the small streams fed by the rain or snow of winter." Such streams are so rare, how- ever, that Colonel Gore, as Sykes relates (p. 40), rode 400 miles from the Heri Rud to Hur, near Kinnan, without seeing a single stream of flowing water. Yet even in Eastern Persia, the worst part of the countr}-, there is another side to the picture. Among the mountains which border the basins, springs and little streams support small villages, where green fields and flourishing orchards drive away the thought 'of the desert for a while. Sad experience has taught the people to utilize the underground water by means of "kanats," long under- ground channels, which start deep underground at the foot of the mountains and gradually approach the surface, bringing water far out into the plains. Where the mountains are high and provide water for numerous "kanats" the plains are well dotted with villages, and even support cities. All of the few rivers are utilized for irrigation, and in Sistan the waters of the Hehnund support scores and perhaps hundreds of villages. In such a countr}- the conditions of life are extremely hard. Strange as it may seem, when the average population is less than 10 to the square mile the country is overpopulated. There are thousands upon thousands of square miles of fine-soiled plain which would be highly fertile if only they could be supplied with water. Ever}-where the cr}- goes up for water, and there is no water. In Western Persia conditions are better, but throughout the basin region of the center and east ever}- drop of water from above ground and below is utilized, and a scarcity of winter snow to .stock the mountains means gaunt famine. The distribution of population illustrates this. Harbors, trade routes, facilities for manufacturing, and the like are of secondar}' importance in detennining the location of cities. The primary consideration is water. Where water is abundant large cities are almost sure to grow up, if other conditions are in the least favorable. Accordingly the large cities of Persia are situated close to lofty mountains. As a rule, the density of population is in direct proportion to the height of the mountains. Sistan appears to be an exception, but, after all, its abundant population is a response to the tremendous mountains of Hindu Rush. The response is far from the cause, because the inter\'euing space can not be cultivated. PHYSIOGRAPHY OF EASTERN PERSIA. 22/ CLIMATE : THE CAUSE OF THE DESOLATION OF PERSIA. The main cause of the desert condition of Persia is its climate. The rainfall of the country- as a whole is estimated as averaging not over lo inches a year. Throughout the greater portion of central and southeastern Persia and the adjoining portions of Afghanistan and Baluchistan the annual rainfall can not be much more than 5 inches. (St. John, p. 7.) The extreme paucity of this will be realized when it is remembered that when the rainfall is less than 1 2 inches a year the region is reduced to a desert and the water supply is too small to be of sen,'ice in irrigation, except in small areas or on the banks of large rivers. The scanty rainfall is usually- divided as follows, according to St. John (p. 7) : "A little rain is hoped for, but not always expected, in November, to sow the early crops. In December there is gen- erally a tolerably- heavy fall of snow, and another in February, followed b>- showers in March and the beginning of April, after w-hich there is nothing but an occasional thunder stonn in the mountains till the next winter." This woful aridity is due partly to Persia's continental position and partly to the high mountains which hem it in. Although 36 per cent of the Persian frontier is bordered by salt water, the country is distinctly continental in climate and in the character of its people. Only the 7 per cent of seacoast in the southeast corner along the Indian Ocean is exposed to the open sea, while the remaining 29 per cent faces the inclosed Caspian Sea and the Persian Gulf, which have little influence in producing a marine climate or people. Moreo\-er, the high mountains which border Persia on even,- side shut out the moisture of the sea and shut in the people. The prevailing winds of Eastern Persia bring \-er)- little rain, as they come from the north and northwest, from a continental region. They- flow into districts of increasing warmth, where their capacity for holding and absorbing moisture is continually increased and the tendency- to furnish rain correspondinglv decreased. The moisture picked up in crossing the Black and Caspian seas is deposited in the lofty Annenian highland and Elburz range, and little is left for the thirsty lands beyond. In summer the northward prolongation of the trade winds combines with the spirally inflowing winds w-hich circle round the Asiatic center of low barometric pressure far to the northeast, and guided by the north-northwest trend of the moun- tains of Eastern Persia produces dry winds of the most extraordinary strength and constancy. Holdich (pp. 145, 334) describes their occun'ence in northwestern Afghanistan and northwestern Baluchistan, but they- are most violent at Sistan, half- way between the tw-o. According to the British members of the Sistan Arbitration Commission, this wind, called the "Wind of One Hundred and Twenty Days," blows almost continuously day and night during the four hottest months of the year, much of the time at the hurricane rate of from 60 to 80 miles per hour. Dust and sand fill the air. The double-pegged tents which withstand the blast make a noise like that of the rigging of a ship in the wildest stonn. The con- tinual hum, flap, clatter, rattle, bang, make mental work almost impossible. Yet the wind has its beneficial aspect. In the houses of the rich an open doorway in the north side is stuffed with small brush. Upon this a servant throws 228 TIIK BASIX OF EASTERN PERSIA AND SISTAN. water, the evaporation of wliich cools the air thai whistles throii<^h and Riuk-rs the interior comfortable. When the wind dies down for a day or two, as happens occasionally, the houses become insufierably hot and myriads of flies and mosquitoes at once swarm everywhere. The strent^th and uniform direction of the wind allow windmills to be constructed with simplicity and ease. The wheel is shaped like an old-fashioned water-wheel, 6 or 8 feet long, and is set vertically on the roof of the mill, directly over the stone which Fig. 149. — Windmills al Tabas. it is to turn (fig. 149). About the wheel is built a high mud wall, which is left open on the south side and on the western half of the north side (fig. 150). The wind enters I through the slit at the north, turns the wheel, and finds an exit to *'"'""^ the south. Often ten or twelve mills are set in a row, east and w^est, and at Neh, northwest of Sistan, I saw fifty. One unfortunate effect of the wind is that in Sistan no fniit can be raised upon trees, and in certain places even melons can not thrive. The wild watermelon, which matures its beautiful but intensely acrid little green and yellow fruits in the dr}' "nullah" beds, has learned to withstand the wind. Normally, the vine spreads in all directions, but under the influence of the wind the branches are bent to the south, and lie in a long bunch so exactly oriented that the plants might almost ser\'e as a compass. Three that I measured were directed S. 3° E., S. 17° E., and S. 11° E. V Fia. 150 Hori- zoQtal section of a Persian wiDdmill. PHYSIOGRAPHY OF EASTERN PERSIA. 229 Evidences of the strength of the wind and the paucity of rain abound every- where. In many parts of the Hehnund delta the fierce "Wind of One Hundred and Twenty Days " has scooped in the smooth plain great hollows 6 or 8 feet deep, 20 or 30 feet wide, and hundreds of feet long. Universally the long axis is directed to tlie north-northwest. At first sight these hollows appear to have been formed by running water, but the testimony of the natives, the location of the depressions where no water could come, the uniform orientation, and the known force and direction of the wind iniite to make it certain that they are of teolian origin. In this same region a peculiar effect was called to my notice by Mr. G. P. Tate, topographer of the Sistan Arbitration Commission. Sistan abounds in ruins made of sun-dried brick. Wherever the old walls stand in a north-and-south direction, parallel to the prevailing course of the wind, they remain standing indefinitely, Fig. 151. — Ruins at the Mil-i-Kasimabad, near Zahidan. These mud wails are at least five hundred years old. Only those in a north-and-south direction remain standing. although gradually worn ver}- thin by attrition. Wherever the walls stand in the other direction, and are exposed to the full power of the wind, they are speedily blown away and disappear entirely. Thus it happens that tlie ruins often present the appearance shown in the illustration (fig. 151), where numerous north-and-south walls stand intact, with almost no east-and-west walls to connect them. Besides these more unusual results, the wind plays its well-known part in beveling pebbles and bricks and in etching out and carrying away the softer parts of the rocks. In winter the winds, although prevailingly from the northwest, are less severe and less regular than in summer. Occasional cyclonic storms are accompanied by southeast winds (St. John, p. 7), which bring the scant rainfall of the couutr\-. At its best the rainfall is sufficient to tinge the mountains with green for a few weeks in spring and to support a scanty population of villagers and nomads ; at its worst, it supports nothing but a few prickly bushes, and famine destroys unnumbered people and animals. The curse of Persia is the aridity due to the continental position of the country and to its rim of high mountains. 230 THE BASIN OF EASTERN PERSIA AND SISTAN. THE BASIN REGION OK IRAN. Before proceeding to a more detailed study of the influence of an arid climate upon the physiography of Eastern Persia, I shall describe the main features of the mountain rim and of the diversified basin which it incloses. Among geographical writers it is customary- to speak of Persia, Afghanistan, and Baluchistan as composing the plateau of Iran. It is well to use the name Iran for the portion of the three countries included within the mountain border, but the tenn " plateau " is misleading. The region is essentially a basin, not a plateau. From the central knot of the Pamirs, a genuine plateau, two mountain passes diverge westward. One, the more northerly, runs west by south under the name of Hindu Kush, and then, as the Paropamisus, turns directly westward and traverses Northern Afghanistan. From a height of 25,000 feet in the Pamirs it descends until in Western Afghanistan the highest peaks rise but 5,000 or 6,000 feet above the sea, and the main range is traversed from south to north by the Heri Rud, the river of Herat. Westward in Persia the mountains incline to the north, and in Kopet Dagh and the mountains of Khorasan reach an altitude of 10,000 feet. Then, inclining once more to the south, they take the name of Elburz, south of the Caspian Sea, and rise to an extreme height of 19,400 feet in Demavend. Lastly, still at tremendous heights, the range swings to the northwest and loses itself in a second mountain knot, the plateau of Armenia. The other mountain mass starts from the Pamir as part of the Hindu Kush, but soon diverges to the south, and running south-southwest traverses the eastern part of Afghanistan and Baluchistan under the name of the Suliman Mountains, rising often to heights of 12,000 feet. As it approaches the Arabian Sea it turns west- ward, and at decreasing heights follows the seacoast until Persia is reached. Here, as in the corresponding portion of the northern range, the mountains are but 5,000 or 6,000 feet high. F'arther west in Persia, however, the mountains soon regain their height, and swinging to the northwest run straight through the center of the countrj- at heights from 8,000 to 14,000 feet, and finally in the highlands of Amienia coalesce with the northern of the two mountain chains which start from Hindu Kush. Between these two chains, and completely inclosed by them, lies the basin region of Iran, which is roughly shaped like a segment of a circle, 1,200 miles long from east to west, and 600 miles broad. This region, most of which is abso- lute desert, contains an area of over 500,000 square miles, and is as large as the twenty of the United States which lie east of the Mississippi River and north of Tennessee and North Carolina ; or, to compare it with a region where physio- graphic conditions are more similar, as large as the five semi-arid states of Colorado, Utah, Nevada, Arizona, and New Mexico. THE TWO B.\SINS OF IRAN. The basin region of Iran contains two chief basins divided into many smaller basins (fig. 152). The largest basin, embracing about three-fifths of all Iran, lies wholly in Persia and may properly be called the Persian basin. The other chief basin, embracing the greater part of the remaining two-fifths of Iran, about 200,000 square miles, contains parts of Persia, Afghanistan, and Baluchistan. It PHYSIOGRAPHY OF EASTERN PERSIA. 231 is sometimes called the Helmund basin, from the main river, but a better name is the Sistan basin, from the lake and swamp into which all the rivers would finally discharge if they did not drj- up on the way. The main portion of this report is concenied with the Sistan basin, but certain features of the Persian basin will also be described, and there will be frequent occasions to refer to Iran as a whole, and also to Turan or Turkestan, as the region farther north is termed. The border region between the basins of Persia and Sistan is important becau.se it represents a line of earth movements extending north and south across the middle of Iran transverse to the main orographic lines. West of this line the Persian basin was uplifted, while to the east the Sistan basin, together with that of the Heri Rud, was depressed. The region of maximum depression forms a long north-and-south strip, the Afghan depression, in which are grouped a number of Pamirs Fig. 152. — Sketch map of the double basin of Iran. notable physiographic phenomena. At the north the low mountains, close to what is now the boundar)- between Persia and Afghanistan, afford a ready pa.ssage between the deserts of the south and those of the north. Elsewhere, for more than 1,500 miles from the Pamirs to the Anneniau plateau, a giant wall of mountains separates Iran and Turan. Here, however (A, fig. 152), the low, rounded mountains aflTord an easy passage which has been utilized by anny after anny, from the time of Alexander through the dajs of Timur and Jenghis Khan to the present century-, when Russia sees in it her easiest road to the south. Here, too, the Heri Rud breaks through the main mountain range and emerges upon the desert of Trans- caspia, the only instance where a river escapes from the basin of Iran. South of the Heri Rud the east-and-west ranges of Afghan mountains come to a sudden end, while those that front them on the Persian side run in the opposite direction nearly north and south. Between the opposing mountains lies the "Nemeksar" or "salt 232 TIIK HASIN OF ICASTERN PERSIA AND SISTAN. playa " of Khaf (B, fig. 152), at the center of an important subsidiarj' basin. Farther south a steep east-facing escarpment, which suggests a fauU scarp, limits the Persian basin, which stretches away in normal fashion westward from the summit, while on the east, at the foot of the escarpment, the smooth " Desert of Despair " (C, fig. 152), strangely broken by buried mountains, spreads its harsh gravels far southward to the lake and swamp of Sistan (D, fig. 152). Onward in the same direction the desert continues to the swamp of Ma.shkel (E, fig. 152), still bounded by the escarp- ment which swings somewhat eastward south of Sistan and bears upon its top the cone of Kuh-i-Taftan (O, fig. 152), the only active volcano of Western Asia. South of all these features the low mountains of southwestern Haluchistan bring the depression to an end (F, fig. 152). The streams flowing into the depression from the east are long and large ; those from the west are so short as to be little more than mountain torrents. GEOLOGICAL HISTORY OF THE B.\SIN. The age of the basins of Iran can onl\- Ik- determined by a stud\- of the geology of the countr)', but of this, unfortunately, we know merely the bare outlines. Not only is the country remote and difficult of access, but the aridity obliges the traveler to hold closely to the roads which usually traverse the gravel-strewn plains. If he makes detours to the moinitains, his caravan may be obliged to spend the night without water. Geological study is at a disadvantage. The work of Blanford (A, p. 468) and the geographical map of Mushketoff show that the mountains bordering the Persian portion of Iran consist for the most part of a main mass of Cretaceous limestone bordered on the inside by a smaller amount of Paleozoic or ancient cr>-stalline strata, and on the outside by concentric bands of Tertiary strata, each of which is less warped than the one below it. The inference is that at the end of the Cretaceous era the mountain borders of western Iran began to ri.se and have continued to be uplifted throughout a large part of Tertiary time. Throughout the Kocene period the sea (Hlanford, A, p. 468, and Vredenburg, p. 168) covered the region which is now occupied by the low mountains of Baluchistan, and also nuich of the interior, judging from the nummulitic limestone which Blanford mentions as being reported from Yezd and Kohnul, and which I fomid abundantly in the mountains northwest of Sistan. It also probably covered the northwestern corner of Afghanistan, for the mountains there consist largely of Tertiar\- forma- tions which seem to be of rather late date. Apparently there was oceanic connection between the Arabian Sea and the Samartian vSea which covered the Caspian region, and the interior of the Iran basin was covered by a marine embayment. When or how the sea retreated or when the eastern borders of Iran were uplifted we do not know. It is clear, however, that during the latter half of tlie Tertiary era Iran had been divided into basins in which subaerial deposition took jilace, as is shown b)- the silty and sandy strata of a prevailingly red color which overlie more uni- fonnly bedded shales of marine or estuarine origin. GEOLOGICAL IILSTORV OF NORTHEASTERN PERSIA. 233 ILLUSTRATIONS OF THE GEOLOGICAL HISTORY OF NORTHEASTERN PERSIA. Although the portion of Iran which I traversed embraces but a small part of the entire basin, it affords illustrations of many phenomena characteristic of the entire region. These fall into groups illustrating, respectively, (i) the non-climatic or more strictly geological historj' of Iran during the Tertiary- and Quaternary eras ; (2) the physiographic results produced by an arid climate during the same time ; and (3) the effects produced by climatic changes during the Quatemarj- era. Each of these groups will be considered in its relation to certain theoretical generaliza- tions, and in relation to the geographic aspect of the countr)-. The following illustrations of the geological history pertain first to the character and conditions of uplift of the mountains on the northeastern border of Persia ; second, to the nature and appearance of the north-and-south break which separates the Persian and Sistan basins ; and, third, to the conditions of warping and deposition in the numerous subsidiary basins. THE MOUNTAINS OF KHORASAN. The term Khorasan is applied administratively to all northeastern Persia from Astrabad to the northwestern corner of Baluchistan. In a n:ore restricted .sense it is the name of the mountainous northeastern corner of the coinitr\' centering about Meshed as a capital. As thus limited Khorasan is one of the most prosperous provinces of Persia, thanks to the considerable number of mountains which rise to the height of 10,000 feet or more ; yet the prevailing aspect is one of sterility. The mountains are very scantily covered with soil, and support merely a few weeds and bushes and an ephemeral growth of grass in spring. Cultivation is almost confined to the valley bottoms and is dependent entirely on irrigation. Each village is an oasis in the midst of a desert, but compared with other parts of Persia the oases are large and numerous, and are often of great beauty, with their fringes of poplars and orchards. This favored province of Persia consists of four parts. On the north lies the broad mountain mass of Kopet Dagh, running northwest and southeast, and fonning the boundary' between Persia and the Russian province of Transcaspia. South of Kopet Dagh lies the so-called valley of Meshed, a narrow cigar-shaped basin or depression. This is bounded on the south by the Binalud range, which runs from the Afghan border northwestward parallel to Kopet Dagh as far as Kuchan, and then turns southwestward until it joins the Elburz Mountains southeast of the Caspian vSea. Within the great arch of the Binalud range lies the fourth division of Khora.san, the little-known basins of Isferayin, Jaga-tai, and Nisliapur, together with the mountains which hem them in. South of all stretches the fearful desert of the Dasht-i-Kavir or Dasht-i-Lut. KOPET DAGH. If the line of the Caucasus IMouutains be projected acro.ss the Caspian Sea it reappears in the low, isolated, and half-buried ranges of the Great and Little Balkhans. Toward the southeast these mountains become broader and higher, and rise into the distinct range of Kopet Dagh, or Kopet Mountain, which, with an 234 THE BASIN OF EASTERN PERSIA AND SISTAN. average breadth of 40 or 50 miles, extends for 350 miles to the Afghan frontier. My own knowledge of the range is based on three caravan jonnieys — one into tlie high mountains south of Askhabad ; anotlier around the eastern end of the range from Uushak, where the railroad turns away from the mountains, to Scrakhs and up the Heri Rud ; and a third from Meshed, via Kuchan, to Askhabad. Kopet Dagh appears to be a fairly mature mountain mass which has recently been faulted and strongly uplifted, and thus rejuvenated. The highest portion, near Askhabad, has been described by Professor Davis (ante, p. 46). Farther to the east the mountains present the same flat-topped appearance, with young \alleys cut sharply into structural slopes which must have assumed their present smooth character during Tertiary times, when the mountains stood lower. This is well illustrated in the back slope of the Gaoudan block, which is without difficulty reached from Anau, 6 miles east of Askhabad. The faulted face of this block, as seen from the Meshed road, is a precipitous escarpment of naked rock. The back slope, on the contrary, is a long, smooth descent, covered with soil, and closely corresponding to the dip of the limestone strata. In this are cut five or six black gashes, the parallel gorges of young consequent streams which have cut .so deeply into the uplifted mountain mass that their sides appear from a distance to be perpen- dicular. East of Dushak, where the railroad leaves the ba.se of the mountains, the strata of Kopet Dagh become softer and are more thoroughly dissected, but the hilltops still retain a flat aspect and the vallejs are steep-sided and narrow. On the southern side of the mountains there is clearer evidence of recent uplift. Looking northward from Meshed toward Kopet Dagh, the plain is bounded by a line of steep bluffs, which rise a thousand feet in one or two great jumps, and continue northwestward scores of miles. They are cut in strata, apparently Cretaceous limestone, which lie nearly horizontal, with a slight roll from northwest to .soiith- east. The steepness and straightness of the mountain front, its slight dissection, and the absence of a stream competent to produce such effects suggest that the escarpment is the result of recent faulting by which the mountains were uplifted and subjected to renewed dissection. Between the top of the bluffs and the remark- ably smooth crest of the range the uplands are rounded and mature in form. These same features continue far to the northwest, but in the neighborhood of Kuchan the bluflfs decrease in height and the escarpment comes to an end. Apparentl}' the fault gradually decreases in amplitude, and near Kuchan, after a course of about a hundred miles, is transformed into a simple fle.xure where the strata of the moun- tains dip south westward and pass under the plain. In the neighborhood of the fle.xure the aspect of the mountains is more mature than in the regions which have been uplifted by faulting. This g^eat displacement along the southern border of the mountains is parallel to the smaller displacements on the north side near Askhabad and seems to be of about the same age. The }'outliful character of the vallej-s in the uplifted block of Kopet Dagh agrees with the steep fault face in indicating that the uplift is of ver>' recent date. For instance, in the mountains north and northwest of Meshed, Curzon (I, pp. 122, 123, 141) describes frequent instances of magnificent gorges from 1,000 to 1,500 feet GEOLOGICAL HISTORY OF NORTHEASTERN PERSIA. 235 deep and so narrow that there is only room for a single horseman to pass between the walls. Northeast of Radkan his party "plunged into a deep and narrow gorge that cut straight into the heart of the rock wall as though some Titan's axe had slashed a savage gash in the solid stone. Its walls were absolutely perpendicular and shaped in parts by the stonns of centuries into windy buttresses and towers, while at the bottom brawled a stream which had hollowed pools in the rocks, and up and across the bed of which it was with difficult}- that our horses could be persuaded to climb. The formation and scener}' of this magnificent gorge, whose walls are in receding terraces, are a precise reproduction on a miniature scale of the unequaled canyon of the Colorado in Utah." This comparison is ver\- appropriate, for just as the horizontal strata of the Colorado plateau were uplifted at the time of the formation of the Grand Wash fault and have for a short time been exposed to dissection, so, at a correspondingly recent date, the slightly tilted strata of Kopet Dagh were uplifted at the time of the formation of the Meshed fault and are now in process of rapid dissection. The drainage of Kopet Dagh appears complex. In part, as at Anau, it is clearly consequent, depending entirely on the attitude assumed by the moimtains in consequence of recent earth movements. The streams follow relatively straight courses in steep-sided young gorges, and the crests of the ridges form the main divides. Oftener, however, as Curzon (I, p. 144) points out, the streams flow along the main valleys parallel to the axis of the mountains for a certain distance, and then, without warning, turn suddenly at right angles and pierce the mountain ranges at almost their highest points, cutting gorges of almost incredible depth and grandeur. "The base of these defiles seldom admits more than a torrent bed blocked with enormous bowlders, and the walls are frequently vertical to a height of from 500 to 1,000 feet. The main divides are seldom the highest ranges or crests. The streams start on one side of the main ranges, and after running parallel to them for a while, break through to the other side, and perhaps run in an opposite direction for a time." Apparently, though the data are ver>' scanty, the drainage of Kopet Dagh was originally like that of the Appalachians, subsequent for the most part, but with antecedent remnants of a former consequent drainage. This has been further complicated by the recent uplifts, which in some places have caused the previous drainage channels to become more deeply intrenched, while elsewhere the}' have given rise to a new consequent drainage. THE MESHED BASIN. The so-called Meshed Valley south of Kopet Dagh is in realit}- a narrow, cigar-shaped basin or depression, 10 or 15 miles wide, and at least 150 miles long from northwest to southeast. On the north it is bounded by the Meshed fault ; on the south it seems to be separated from the mountains of Binalud by a simple flexure. At Kuchan, in the western half of the basin, its floor is arched where the Meshed fault becomes a flexure. As a result, the basin is occupied b\- two streams, probably consequent, one of which, the Atrek, flows northwest to the Caspian Sea, while the other, the Meshed River, or Keshef Rud, flows southeast to the Heri Rud ; 236 THE BASIN OF EASTERN PERSIA AND SISTAN. both traverse the open plain at first, Inil later enter gorges, one of which, along the Atrek, is said to be so deep and narrow as to afford magnificent scener)- and to be impassable fi^r caravans. THE KUCHAN KARTHQOAKE. In connection with the earth-movements by which the Meshed basin has been differentiated from Kopet Dagh and Binalud Knh it is interesting to note that earth- quakes are still common in this region, and are most violent at Kuchan, where the Meshed fault ends in a flexure. In November, 1893, an unusually severe shock destroyed Kuchan, and is said to have killed from 5,000 to 7,000 people. So com- plete was the destruction that in 1904 the place had almost lost the semblance of a town and was fast becoming a mere shapeless mass of ruins. The surviving inhab- Fig. 153. — The ruins of Old Kuchan. itants moved to a location about 10 miles farther east and have there built a new town, modeled after the Russian pattern, with broad streets shaded with numerous trees. Earthquakes still occur very frequently, but are reported to be much less violent at New Kuchan than at the old city. A few of the people of Old Kuchan refused to leave the ruins after the great earthquake of 1893. Digging among the shat- tered houses, they piilled out old timbers and set them up to form houses which should be both rain-proof and earthquake-proof. At first the timbers were merely set up A-shape against a ridge-pole, like roofs without walls, and the interstices' were filled with bushes and the whole plastered with mud. When a more pre- tentious house was desired, a second structure of the same sort was erected parallel to the first, and the intervening space was walled in and bridged with a flat roof. Old Kuchan consists to-day of a heap of niins on which are irregularly scattered earthquake-proof houses containing from one to three rooms (fig. 153). GEOLOGICAL HISTORY OF NORTHEASTERN PERSIA. 237 THE BINALUD RANGE AND THK NEIGHBORING BASINS. Little is known of the third and fonrth divisions of Khorasan. I have seen nothing of the basins and shall not attempt to describe them. The Binalud ^Mountains, as seen from the north, present somewliat the same \ontliful ajjpearance as Kopet Dagh, though to a less degree. I was told by Mr. Clemenson, of Meshed, that some of the valleys are as deep and narrow as those of the northern range. Farther south, however, the youthful outlines are lost and the mountains assume a mature appearance. The component rocks also change in character and become largely igneous or of Paleozoic age. It appears that the uplifting of the mountains of Eastern Persia has proceeded gradualh- from south to north. On the edge of the Dasht-i-Kavir the mountains are mature, farther north in the Binalud range they are young, while still farther north in Kopet Dagh many features are exceedingly }-oung. In Central Asia the same thing seems to be taking place. Step by step the ranges are gaining in area at the expense of the basins, and the mountainous areas of the central massif of Asia seem to be encroaching northward upon the great plains. THE .\FGH.\N DEPRESSION. THE HERI RUD VALLEY. The Afghan depression is bounded on the north by the low mountains through which the Heri Rud has cut its way out from the basin of Iran, (iatheriug its waters from the snowy heights of Hindu Kush, in the most inaccessible portion of northern Afghanistan, the Heri Rud flows westward for 300 miles between towering mountain ranges which gradually decrease in height and finally come to an end at the edge of the Afghan depression. Here the Heri Rud turns abruptly north, and after threading its way through a gorge emerges upon the plain of Transcaspia. There, after receiving the waters of the Keshef Rud from Meshed, it takes the name of Tejeu River, and soon loses itself in the swamps and sands of the Turkoman desert. Where the Heri Rud crosses the mountains, the eastern portion of the northern border of Iran appears to be offset to the south. The Paropamisus appears to be the continuation of Kopet Dagh, and the mountains south of Herat the continua- tion of the Binalud range. The eastern mountains lie roughly 50 miles south of their Persian counterparts. This break between the ranges of Persia and Afghan- istan causes the depression through which the Heri Rud escapes to the north. Little is known of the mountains which border the depression. Those on the west at the end of Kopet Dagh, according to Mushketoff, consist for the most part of Cretaceous limestone, but I saw several large basins and other areas where the prevailing fonnations are of Tertiar)- age. The topograph)- on the whole is mature ; it probably corresponds to that which would exist farther west in the neighborhood of Meshed and .\skhabad if no recent uplift had taken place. East of the river the topography is still more mature. Holdich (p. 113), whose opportunities for observation were extensi\e, describes the country north of Herat as so mature that, although the passes rise to a height of 4,800 feet, wagons can be driven across the mountains in spite of the absence of roads. In the region about 60 miles north of Herat, which Mushketoflf crroueouslv, I think, marks as Triassic, Holdich 238 THE BASIN OF EASTERN PERSIA AND SISTAN. (pp. 133-134) speaks of the "soft-sided" hills as being worn away so fast that "the mountains ran down to the plains in rivulets of mud." Because of this rapid process of degradation the mountains north of Herat "are certainly not such as were described by classical writers two thousand years ago." The wonderful rapidity of erosion is illustrated b>- a stoiy related by Holdich (p. 135) of a place in this region where the hilltops consisted of a stratified, somewhat loess-like formation of recent date. In descending from the top of a hill during "quite an ordinary hailstorm . . . I was up to my knees in a moving mass of liquid mud. ... By evening that mud had spread out in a thin but very measurable sheet of surface soil far over the plains all around the hill ; and the hill was definitely smaller and the plains definitely higher than they had been the day previous." It is possible that the region is as }oung in years as Kopet Dagh, although the topography is mature by reason of the softness of the strata. A section along the Heri Rud from Serakhs southward leads to the same conclusion. At first the stream flows in a terraced valley intrenched some 20 or 30 feet below the alluvial plain which stretches indefinitely northward. Toward the south, however, it traverses a region of low hills composed of an alluvial deposit, which seems to be of the same character as the plain and as the deposits which are now being laid down by the ri\er, although older than either. Where exposed in section by the undercutting of the river, as at Nauruzabad, 25 miles south of Serakhs, for example, the alluvium consists of fine stratified silt, brown in color, l=Cretaceous limestone; 2=Tertiary brown limestone; j^Tertiary brown sandstone; 4=Tertiary thin clayey limestone ; 5— Tertiary soft sandstone ; 6= Tertiary impure yellow limestone ; 7=Ter- tiary reddish-brown sandstone ; 8= Tertiary white limestone. Fig. 154. — North and south section along the Heri Rud at Pul-i-Khalun. and, in some layers, with a texture much like typical loess. Overlying this is thick gravel, and interstratified with it are bands of gravel lenticular in shape and some- times reaching a thickness of 5 or 10 feet. This deposit, formed apparentl}- by the ancient Heri Rud, covers most of this corner of Transcaspia from the Afghan border northward. Often it is concealed by drifted sand or loess ; sometimes it is interrupted by projecting bits of an older sandstone, presumably of Tertiar>' age, which dips gently northward where I saw it at Pul-i-Khatuu salt lake. Back from the river, east of Pul-i-Khatun (Ladies' Bridge), the soft allu\-ium assumes the form of low, rolling hills, well graded and mature, which toward the southeast gradually increase to a height ot 4,000 feet. The main valleys are bordered by terraces cut for the most part in gravel. At Pul-i-Khatun the alluvium comes to an end where the Heri Rud emerges from the mountains through a narrow gorge composed of the Tertiar}' strata shown in the accompanying section (fig. 154). These strata form a smoothly truncated ridge, in which the river has cut a sharp notch. South of this Tertian,- ridge lies a great body of calcareous Cretaceous strata forming the main mass of the moun- GEOLOGICAL IILSTORY OF NORTHEASTERN PERSIA. 239 tains. The mountain tops are smoothly rounded ; the streams, which seem to be in process of becoming subsequent, sometimes follow the strike of the strata, but often break away, and there are a number of young gorges such as that of the Heri Rud. The histor}' of the mountains around the Heri Rud seems to have been similar to that of the more western parts of Kopet Dagh. Afteii the Tertiary era was well under way, the Cretaceous formation and the older Tertiary- strata were uplifted and the softer strata, at least, were highly folded. Erosion then reduced the countn,- to the rounded character which the mountain tops now show and to the flat condition which is seen in the flat-topped Tertiar>' ridge at Pul-i-Khatun. The waste from the mountains formed the vast alluvial or piedmont deposits through which the Heri Rud had now cut its way below the ridge. At length another uplift occurred corresponding to that of the Meshed fault, though on a much smaller scale, and possibly at a diflferent time. The land was raised to approximately its present height, and the work of cutting the Pul-i-Khatun gorge and other young valleys was inaugurated. Since the completion of that work, or during the latter part of its accomplishment, gravel terraces were formed. The topography of to-day consists of three portions — the mature topography of the mountains, remaining as an inherit- ance from a preceding c}cle, the >oung topography of the gorges, and the mature topography of the uplifted piedmont deposits, which is as young as the gorges in years, although n^ature in form. THE EXTINCT LAKE OF ZORABAD. Along the Heri Rud, within the area of Cretaceous limestone south of Pul-i- Khatun, lies the basin of Zorabad. On the Persian side of the river it extends northwest and southeast parallel to the mountains for a distance of about 20 miles, with a width of from 6 to 8 miles. On the Afghan side the limits are not known, but they are probably not extensive. This basin formerly contained a lake, as is shown b}- an extensive deposit of pure, bluish-white clay or marl, ver)- homogeneous and almost unhanded, into which the terraced streams have cut to a depth of at least 100 feet. Upon the clay, and sharph- contrasting with it, lies a hard cap of from 5 to 20 feet of coarse gravel. Near the Heri Rud, in the deepest portion of the basin, both foruiations increase in thickness. The clay, as would naturalh- be the case with a lacustrine deposit, preser\-es the same character. The conglomerate becomes finer in texture and at last passes into silt. Near the edge of the basin, on the south side at least, the clays and the overlying gravel are slightly warped and have been beveled by a grade plain fonned at the begin- ning of the cycle, during which the present valleys were incised in the lake deposits after the draining of the lake. Here it is seen that under the clays, and apparenth" conformable with them, lies a thick series of sediments, consisting of sandstone and conglomerate in the upper portion and the thick shale a=shale ; 6=sandstone and conglomerate ; c=lacustrine clay ; rf^recent gravel. Fig. 155. — Section near Khitayi, on the southern border of the Zorabad basin. 240 TIIK liASIN OF EASTERN PERSIA AND SISTAN. below (fig. 155). The whole series has been much folded along the edge, but appears to lie more nearly in its original position out toward the center of the basin. The known facts in regard to Zorabad are too few to warrant any hard and fast conclusions as to its liistory. The most probable lupothesis is that in early Tertiary times apparently a body of shales was deposited under what were presumably marine conditions. At length the water retired and heavy conglomerates and sandstones were deposited either subaerially or in very shallow water of fluctuating depth. Toward the close, or perhaps during the progress of this deposition, earth-movements were in progress which dimini.shed the size of the basin and uplifted its sides, as is shown by the crumpling of the strata along the edge. Eventually the northern border was raised so high that the Hcri Rud was checked and the basin was con- verted into a lake where clayey marls were deposited. It is proljable that these movements were contemporaneous with those which uplifted the alluvial deposits southeast of Seraklis and inaugurated the present cycle of erosion, for the cutting of the gorge at Pul-i-Khatun must have proceeded pari passu with the draining of the lake which now ensued. After the lake had disappeared the lacustrine deposits were covered with the subaerial gravels which are so common in arid regions. To-day the deepening of the gorge of the Heri Rud has permitted the dissection of both the clays and the gravels. The most notable fact in regard to Zorabad is that we have here on a small scale the same phenomenon which will presently be described in other basins of Persia, and which seems to have taken place in some of the basins of Turkestan. The area of deposition along the edges of the basin is continually in process of folding, and tlie folding progresses gradually inward. THE AFGHAN DEPRESSION SOUTH OF THE RUSSO-AFGHAN BOUNDARY. On the southern rim of the Zorabad Ixisin the fieri Rud enters the ancient lake bed through a deep gorge cut in Cretaceous limestone and probably of nearly the same age as the corresponding gorge of Pul-i-Khatun on the north side. Upstream the river flows through a broad open valley, which is in realit\- another large basin extending northwest for 60 miles past Turbat-i-Sheikh Jam. The innnediate river valley is bounded by the broad terraces cut in gravel and in an underlying deposit of unconsolidated silts. The silts are sliglitly warped and are truncated by the terraces. They will l:)e described later. Opposite the southeastern corner of the Jam basin, and offset to the south from it, just as the mountain ranges on the two sides of the Heri Rud are offset from one another, lies the basin of Herat, Inroad at first, but gradually contracting into the stupendous gorge of the upper river. The Jam-Herat basin is bordered on the south by low hills, cliiefl)- of sandstone, I;e>ond which the smooth, white sheet of the " Nemeksar," or playa of Khaf, and the smaller sheets of its neighbors fill the bottom of a depression which is chiefly remarkaljle for the large number of half-buried momitains which rise on every hand like islands in an archipelago. It seems as though a once mountainous region had been depressed to form a hollow, in which the mountains still stand as of old, although some have been buried in detritus to the waist, others to the neck, and some are doubtless wholly hidden. GEOLO(;iCAL HISTORY OF NORTHEASTERN PERSIA. 241 Thus far, for a distance of 250 miles from vSerakhs on tlie north to the farther side of the basin of "Nemeksar" on the south, the Afj>^han depression presents the appearance of an undulatin<>- hollow with nearly equal slopes from east and west. Farther south, however, the west side of the hollow becomes short and steep, and there seems to have been faulting^ as well as warping. Near Meliki, at the southern end of the Nemeksar basin, the western boundary of the depression consists of a long line of mountains running nearly north and south, with a remarkably straight front. They are not dissected by the deep re-entrant valleys filled with gravel which are so characteristic a feature of most of the mountains in the basin of Iran. The spurs between the valleys end alnu]3tly and steepen toward the front as though they were the remnants of the facets of a fault scarp ( Davi.s, c, p. 14(8-1 54). Apparently this steep escarpment marks a relatively recent fault with a heave of many hundred feet on the west side. This is borne out by the appearance of the top of the upheaved block. From a study of the map and from the appearance of the escarpment from below one expects to ascend to the top of the ridge and enter a region of ridges and vallevs like the ordinar)' mountain districts of America and Europe. The top of the escarp- ment fulfills this expectation, for it is a distinct ridge, at an elevation of 5,000 to 7,000 feet.* Toward the west the ridge descends much less steeply than toward the east, and at a height of about 4,000 feet merges into plains of gravel and silt of the same sort as those on the down-faulted side, except that they stand some 2,000 feet higher and the mountains surrounding them are le.ss deeply buried in gravel. In other words, the country on either side of the fault appears to have been origin- ally of the .same type, the ordinary mountain-girt basin type of Eastern Persia. One side was uplifted and expo.sed to somewhat greater rainfall and erosion ; the other was depressed and exposed to diminished rainfall and increa.sed deposition. Hence the upland is a mountainous region containing basins floored with gra\el ; the lowland is a basin, almost filled with gravel, from which project mountain tops. Between the hollow of Nemek.sar and the much larger hollow of Sistan lies the Dasht-i-Naumad, or Desert of Despair, the central portion of which can not be crossed for lack of water. It does not appear to differ essentially from the lifeless desert wastes of silt and gravel which floor the hollow of Nemeksar. On the edges, at least, it contains the usual complement of buried mountains. Evenwhere dreariness and desolation are the rule. The Desert of Despair is a place where men and animals die of hunger and thirst and their companions have no pit%-. .\ caravan of Afghans which crossed our track was about to return across the northern edge of the desert with salt from Nemeksar to be sold at Sebzavar in Afghanistan. They reported that on the outward journey the>' had been delated and several of their number had died of hunger. " But had the rest of you no bread ? " " Yes, we had enouiih, but we could not give any to them, for we might have suffered from hunger ourselves.'' The desert makes men lose everj- sentiment except the desire to get safel)- to the other side. *Tlic ridge consists of a cap of limestone lying unconforniably on a complex of igneous rocks composed chiefly of dark traps shot tliroiigh with dykes and masses of light-colored felsite, and occasionally interspersed with bodies of highly metamorphosed slate. 242 THE BASIN OF EASTERN PERSIA AND SISTAN. The remainder of the Afghan depression may be smnmed up briefl>-. In the southwestern corner of Afjjhanistan lies the hollow of Sistan, bounded to the west by the unknown, and probably unknowable, escarpment of Palan Kuh (Panther Mountain). Then comes the God-i-Zirrah in Baluchistan, a part of the Sistan hollow; and lastly, to the southeast, the hollow of Mashkel, west of which, near the edge of the escarpment, lies the active volcano of Kuh-i-Taftan. From north to south the Afghan depression, varietl as it is in character, forms a continuous whole. So, too, from the Jam basin southward, does the escarpment which foniis the western edge and dixides the basin of Sistan from that of Persia. It is not by accident that the boundary between Afghanistan and Persia is located along this line. The Heri Rud, so long as it flows in a gorge, forms an unmistakaljle frontier which can not easily be crossed. The deserts of Nemeksar and the Desert of Despair form an even more effectual barrier. In two places the frontier is weak. One is where the Heri Rud turns northward and the plains of Jam and Herat coalesce. At this point there is no natural barrier, although the land southwest of the bend of the river is so nearly desert and of so little value that it affords small provocation for quarrels. The other weakness is at Si.stan, where the boundar)' arbitrarily bends eastward to the Helmund River, leaving the incomparable natural boundary- afforded by the absolute desert at the base of Palan Kuh. Geographically, the whole of Sistan belongs to Afghanistan. Until the political boundary coincides with the natural boundary it is not to be expected that Persia and Afghanistan can avoid quarrels. THE TERTIARY HISTORY OF THE BASINS OF EASTERN PERSIA. In a preceding paragraph an outline has been given of the histoiy of one of the minor basins of northeastern Persia. The Zorabad Basin. — Apparently the Zorabad basin was first occupied by the sea and later became dr)' land. Then, by the warping of the earth's cni.st, it was con- verted into a lake, which in time was drained by the cutting of a gorge. As the water of the lake receded gravel was washed in from the sides and covered the lake deposits. Since that time the gorge at the outlet has been cut deeper, the \'arious deposits have all been more or less dissected, and terraces have been formed. At inter\'als during the progress of these events warping has gone on in such a fashion that the size of the basin has continually diminished and all the deposits except the most recent gravels have been warped along the edges, although apparently remain- ing horizontal in the center of the basin. Most of this histoiy probably belongs to Tertiary times, although the dissection of the lake deposits and the formation of the terraces almost certainly belong to the present geological era. In order to understand the geological history- of Persia it will be necessary to ascertain to what extent a similar series of events has occurred in other basins. What few facts are known indicate that the history of all the basins is similar to that of Zorabad, with the exception of the lake episode. The only lakes of which we have record in the other basins occurred at a later time and were due to changes of climate rather than to warping of the crust. GEOLOGICAL HISTORY OF NORTHEASTERN PERSIA. 243 The Jatn Basin. — ^The deposits of the Jam basin south of Zorabad are disclosed in a number of terraces along the Heri Rud and its tributaries. They consist of fine- grained brown silts, neither sand nor clay, but between the two. Most of the silts are reddish-brown in color, others are brown, brownish-purple, or green. They contain gypsnm in thin and verj' pure transparent layers, which are some- times so abundant that the ground is white with fragments. Often the strata lie horizontal, but there are many places where warping has taken place. For instance, south of Danidue a terrace 180 feet high consists of a cap of coarse slaty gravel lying unconformably on silts dipping 6° N. The edges of the Jam basin were not seen, and we can not be sure whether the amount of warping increases from the center outward. An interesting point in regard to the Jam deposits is that as a whole they much resemble the Moencopie beds which occupy so large an area in the plateau region of the United States (Goldthwait, pp. 203, 205, 210). Not only is the general character of the two formations similar, but the brilliant color and peculiar fonn of the cliffs are strikingly alike, while in each case a gravel cap protects the soft underlying silts. Even the ten-aces present the same appearance, although those of America are structural, while those of Persia are fluviatile. The Ncmcksar Basin. — In the Nemeksar basin, 75 miles south of the Jam River, many of the phenomena of the Jam basin are repeated. The gravel-capped terraces bordering the playa consist of a soft, fine silt, mostly red, but sometimes slightly green, in which are numerous thin layers of transparent crystalline gypsum. No warping of the silts was here observed, but the\- were seen onh- near the center of the basin. The Chau Bineh Basin. — At Chau Bineh, near Durukh, about 90 miles south- east of Birjand, thick warped clays were noted, purple, red, and green, like those of the Jam basin. They lie unconformably against a mass of ancient volcanic rocks full of serpentine and iron pyrites. The Durukh basin, on the edge of which they lie, is tributary- to Sistan. The Ouihak Basin. — This basin and the following one lie on the edge of the main basin of Persia, the Daslit-i-Lut, and would discharge into it if supplied with sufficient water. Yet each possesses its own individuality and is a separate basin with its own "kavir" or salt playa occupying the lowest portion. The basin of Chahak lies two days' journey, 40 or 50 miles, northwest of Birjand, on the road to Tun. Around the playa at the bottom of the basin the waves of a fonner lake, have cut bluffs of considerable height. For the most part these are composed of a hard cla>- shale, partly green and partly red, which usually lies horizontal, although in some places it is much folded. Three or four miles northwest of the village of Chahak the bluffs, about 100 feet high, are capped with la\'a and disclose the following section, beginning from the top : Feet. Dark volcanic trap 20 Green clay shale 40 Pink shale 10 Yellow clay shale S Green clay shale 20 244 THE BASIN OF EASTERN PERSIA AND SISTAN. The lava cap lies horizontal ; the shales dip about 20° to the north or north- west. The shales are bnt slightly consolidated, and do not appear to be of great age. Their resemblance to the formations of Sistan, to be described later, is so close that it may be significant. Twenty miles southeast of the above section, at a point a few miles west of Husseinabad, on the main tributarj' of the Chahak basin, the valley walls consist of highly folded green clay shales of much the same composition as those of the section just given, although more iiidurated. It is probable that they form the lower members of the same series, for similar shales are seen at intervals between the two sections. The Husseinabad shales show a strong overthrust from east to west ; that is, out from the mountains toward the great basin of the Dasht-i-IyUt (fig. 160). It should be noted that these beds, like the older shales at Zorabad, must have been deposited in water of at least moderate depth, which preserved nearly the same conditions for a long period. The recent strata at Chahak, on the other hand, like those at Sistan, seem to have been deposited under changing condi- tions, which favored first the deposition of green and then of pink cLins. In the next basin we shall come to pink beds deposited entirely under subaerial conditions. The Bajislan Basin. — Bajistan, 40 miles north of Tim, lies on the southern margin of a large "kavir," or salt playa, which, according to Curzon's map, extends some 75 miles northeast and southwest, and from 10 to 30 in the other direction. The playa, at most times, contains a ver)- small amount of standing water surrounded bv a broad white plain of salt mixed with silt, nniddy in winter, dry and powdery in summer. About 25 miles northeast of the edge of the playa and 20 miles south- west of Turbat-i-Haideri, the gently sloping plain of Bajistan rises into a low line of hills a thousand feet above the " kavir." These hills are composed for the most part of reddish or pink silts which attain a thickness of several hundred feet. At intervals the silts are interrupted by layers of sand from 10 to 20 feet thick and of a reddish-brown color. These strata of alternating silt and sand are soft and uncon- solidated ; they are folded to such an extent that dips of 15° are not uncommon, and they extend around the edge of the basin and along its sides for some miles. Apparentl)- they were deposited in the basin at a time when it was larger. They have since been uplifted and warped, while the central deposits into which they merge have remained midisturbed. In stnicture, color, and texture the Bajistan strata suggest the more sandy portions of the pink strata at Sistan. They bear a stronger resemblance to the pink deposits of the Tertiary in Central Turkestan and the Kashgar basin. To a less degree they resemble the deposits of the Jam and Nemeksar basins, although at Bajistan no gypsum was noticed. It is probable that all these red and pink strata are of subaerial origin or were deposited in verj- shallow saline playas or estuaries. No other explanation seems to account for the absence of fossils, the presence of gypsum, the red color, and the alternations between sand and finer silt. OTHBR LOCALITIES. Blanford cites a few instances of deposits which apparently belong to the same class as those mentioned above. Near Abarik («', p. 485), on the edge of the Dasht-i-Lut between Bam and Kinnan, " are some high cliffs of shales and con- GEOLOGICAL HISTORY OF NORTHEASTERN PERSIA. 245 glomerates, ver>' slightlj- consolidated, and to all appearance of comparatively recent origin. The shales are rather brightly colored, greenish-white, red, etc. . . . The beds near the river are contorted and sometimes vertical ; farther away they become more horizontal and appear to pass up into the alluvial beds of the great plain to the northward." Elsewhere (/;, pp. 493-494) Blanford speaks of red shales, or ferruginous shales and sandy beds, sometimes banded red and white, and often much decompo.sed, which lie in tilted positions against the limestone of the mountains on the edge of the basins west of Kirman and seem to lia\'e been brought to their present positions by faulting and folding. From the description it seems as though these beds must closely resemble those of Hajistan. SUMMARY. The facts set forth above, so far as they warrant any conclusion, suggest that in Eastern Persia the lower strata of the basins are generally greenish shales, which are now exposed along the edges of the basins where they have been extensively warped and compressed. Above them occur reddish silts containing more or less sand and g\'psum and warped like the underlying shales, although to a less extent. In certain places toward the top of the series the red strata alternate with green clays. Above all lie the deposits of silt and gravel which are to-day accumulating. Although these different strata show varying degrees of warping along the edges of the basins, it is noticeable that toward the centers they approach the horizontal position. It is probable that in the centers of many of the basins an uninterrupted series of strata has been deposited from the time of the post-Cretaceous uplift of the country" until now. At first a shallow sea or large lakes probably occupied the central portions of Iran and allowed the deposition of the green shales. Later, as the great basin was broken into smaller basins, the larger bodies of water gave place to smaller ones, and these, under the influence of a drj- climate, gave place to playas or shallow salt lakes where the prevailing deposits were reddish silts. Still the process of deepening the basins and decreasing their area went on, with the result that the green shales were more highly warped and the red deposits were also uplifted along the borders of the basin and were exposed to erosion. Meanwhile the superficial deposits which now cover the plains were laid down and the country assumed its present form. It is not to be supposed that ever)' basin has gone through exactl)' the same process, or that a single process has everywhere taken place at the same time. Accidents have intervened. At Zorabad the damming of the Heri Rud formed a lake and greatly altered the course of events. At Sistan, and probably elsewhere, a series of lakes appears to have occupied the basin during the glacial period. Nevertheless the general course of events was a gradual progress from larger basins to smaller basins, and from subaqueous to subaerial deposition. 246 THE BASIN OF EASTERN PERSIA AND SISTAN. PERSIA AS A TYPICAL EXAMPLE OF AN ARID COUNTRY. Eastern Persia is in the stage of physiographic development where the influence of aridity is most prominent. Tlie climate of the world as a whole is such that soil is abundant, lakes have outlets, rivers discharge into the sea, and agriculture can be carried on without irrigation. Such conditions are .so common that it is hard to realize that they are merely the effects of one special variety of climate. In Persia, however, where the whole aspect of nature is different from that to which we are accustomed, it becomes easy to appreciate the influence of climate. The funda- mental difference between the topography of Persia and that of a well-watered country like the eastern United States is that in the latter the main forms are deter- mined by the forces of erosion acting under the guidance of rock-stnicture and rock- texture, while in Persia a large proportion of the main fonns are detennined by deposition, which tends to conceal and nullify the influence of rock structure and texture. This can best be illustrated by considering the life history of Persia. THE CYCLE OF EROSION AND DEPOSITION IN PERSI.\. The changes through which Persia has passed in the earlier stages of its de\-elo]> ment, and also those of the future, must in part be inferred, for, so far as I am aware, no part of the country is in the stages of extreme youth or old age, and no tjpical examples of these stages have been described elsewhere. The present cycle of erosion in Persia was introduced by the formation of inclosed basins, the most striking topographic feature of the couutr)-. As we have already seen, the basins are not due to any peculiar form of warping, but rather to the arid climate which has long prevailed. This is well exemplified in the three basins of Zorabad, Jam, and Meshed, in the northeastern corner of the countr}-, which receive an abundant supply of water from high mountains, and hence are provided with outlets and are fast being transfonned into valleys of erosion. During the youth of the country these three basins, like their neighbors, such as Pul-i-Khatun, to be described later, Nemeksar, Bajistan, and others, were completely closed and in one case at least contained a lake. During early youth it is probable that all the basins were com- pletely closed. At first their development must have proceeded in much the same way as that of the lake-filled basins of moister regions. The mountains also appear to have developed in the same wa)- as in lands of greater rainfall. Kopet Dagh is the best Persian example which I have seen of young mountains developed under conditions of aridity. Here, however, much of the topography is mature, and the altitude of the mountains has increased the rainfall so that the erosion is not greatly different from that of America and Europe. A better example of young mountains in an arid region is furnished by the southern border of the Tian Shan plateau on the edge of the Kashgar basin. As there exemplified, the chief characteristic of such mountains is extreme sharpness of form and utter nakedness. PERSIA AS AN EXAMPLE OF AN ARID COUNTRY. 247 MATDRITY. As youth advances toward maturity the difference between the physiographic fonns of a moist country and of a dry countr>- increases apace. At the beginning of maturity in a laud of sufficient rainfall the lakes have for the most part been drained, and the topographic fonns are almost universally due to erosion guided by the struc- ture and texture of the rocks. In Persia, the t>'pical drj- countrj-, on the other liand, almost none of the lakes have been drained, and the proportion of the surface where topographic fonns produced by erosion prevail, has reached and passed a maxinuim. Indeed, the process of decreasing the area subject to erosion goes on from earl}- jouth until old age, and is perhaps the most prominent characteristic of the activities con- trolled by an arid climate. The streams which come from the mountains laden with detritus are compelled to deposit much of their load on reaching the foot of the moun- tains and changing from a steep to a gentle grade. Even a small stream can flow a long distance in a very arid region, provided it is confined to a small rock channel where there is little opportunity for evaporation. As soon, however, as a region of deposition is reached, the stream begins to spread into many channels, which reduces the already diminished velocity and causes further deposition. Moreover, the stream itself quickly comes to an end, for much water is lost by reason of the larger area exposed to evaporation in the many channels, and even more sinks into the thirsty gravel. For this reason the small running streams of Persia are almost entirely confined to the higher mountains and are continually growing shorter Each new addition of gravel to the fan of a stream represents a decrease in the height of the mountains which in the course of ages is sufficient to cause a decrease in rainfall. It also raises the height of the fan itself, and compels the stream to divide and to lose itself in the gravel at a higher elevation than fonnerly. Both these processes tend to shorten the streams and cause them to deposit their loads higher and higher, building up the fans indefinitely. Everjthing tends to increase the areas of deposition until finally basin coalesces with basin ; the lower hills are buried out of sight ; those of greater height rise as islands in vast expanses of gravel ; and even the highest nioimtains are half-buried in great fans of the same material. Thus in full maturity only the mountains present fonns due to erosion, and even of the mountains the lower portions are buried by constantly increasing products of deposition. This is the condition which has been reached in Eastern Persia south of Binalud Kuh. One of its prominent characteristics is the isolation of the mountains, which is well seen in the basin of Nemeksar. One of the most striking examples is in the playa of Kulberenj, south of the main playa of Nemeksar. From the ver)' floor of the playa rise several small, dark islands, whose roots seem to descend beneath the plain as though these were the pointed tops of what once were high hills or mountains. The erosion 0/ the mouiitaiiis. — Another prominent characteristic of the mature mountains of Persia is their nakedness, roughness, and sterility. In a young country it is to be expected that there shall be large areas of naked rock, but in a mature country-, if the rainfall is abundant, most of the surface, except the imme- 248 THE BASIN OF EASTERN PERSIA AND SISTAN. diate valley-sides, is graded, and thus covered more or less deeply with soil. Eastern Persia, however, is so arid that the ordinary state of affairs is reversed. All the mountains, whether young or mature, are characterized by nakedness. In the mountains between Neh and Sistan, for instance, which are now passing from youth to maturity, the aridity is so great that the growth of plants is prevented, and free play is allowed to the activity of the wind. The result is that the hills are almost ab.solutcly free from soil and present a remarkal)lc degree of roughness. On one small mountain near Aliabad, for instance, the highly lilted shale of which it is composed stands entirely naked, and e\en the cracks between the fragments are free from bits of soil. In stnicture, although not in color or texture, the mountain suggests a great mass of small quartz crystals tied loosely into enonnous bundles, with the {xjints up. Another good example of the influence of aridity is found in the neighborhood of Birjand. Here the moimtains are composed of dark volcanic rocks, and their main outlines are not shar]i and .steep in outline like tho.se among the regions of stratified rock to the south, wliicli have just been described. They lie rather in long ridges with rolling crests, rising to a nearly e\en height, but yet with considerable variation. The sides rise with a steep but by no means abrupt slope, and the drainage is completely established and seems to have become subse- quent. In a well-watered country such mountains would be wholly covered with soil and vegetation, and their rounded outlines and graded slopes would leave no doubt that they were in the stage of maturity. In the arid region of Birjand, on the other hand, but few of the slopes are graded, vegetation is \ery rare, naked rock is as prominent as soil, and many of the small valleys have precipitous sides. Everjwhere the same phenomena appear. Most of the mountains are rocky and jagged, with numerous small, sharp peaks and little points ; and ven' often a small hill, which forms but a tiny island in a plain of gravel, still retains the mggedness and sharpness of outline of an Alpine peak. Graded slopes are not a feature of maturity in an arid climate, for the mountains may be nuich reduced in height, the drainage may become completely adjusted to the strata, and all the other characteristics of maturity may be de\-eloped before the graded condition makes its appearance. Mature basins. — In the maturity of an arid mountain region the basins are the most important and characteristic feature. In the Persian basins the rock floors are hidden far from sight ; the deposits of Tertiary- age which were first laid down in them are also invisible for the most part. Only the deposits which are now in process of fonnation contribute largely to the geographic appearance of the country- as it exists to-day. In Eastern Persia these modem deposits are in part aqueous and in part seolian. The latter vary little in texture, and consist largely of fine sand, cover- ing the drier plains and sometimes mantling the leeward side of the hills. Their most remarkable development is at Sistan (Plate 4 and fig. 169), where the violent winds move the sand with phenomenal celerity and heap it into dunes of great height, which are to-day fast encroaching on areas of gravel and silt. The aqueous deposits, on the other hand, var\' from the finest clays of lacu.strine deposits, through the silts and sands of plazas, to coarse gravel and bowlders in the huge piedmont fans and in the mountain valleys. The basin deposits seem to occur ahnost invariably in one PERSIA AS AN EXAMPLE OF AN ARID COUNTRY. 249 order of superposition, namely, silts or other fine materials at the bottom, then gravel, and lastly wind-blown sand on top. It is probable that this order of superposition represents the ordinary- sequence of events in a countrj- where basin-making and desiccation are both in progress. The aqueous series of basin deposits. — The general appearance of the basin deposits is well described by Blanford («, pp. 495-496) : In the smaller plains, and in the larger deserts at a short distance from their margins, the sur- face usually consists of very fine, pale-colored rather sandy cart^h, which, although barren in gen- eral, is fertile wherever irrigation is practised, unless, as is not unfrequently the case, it is strongly impregnated with salts. . . . The margins of the desert plains . . . usually consist of a long slope covered with gravel and bowlders, and with a surface inclination of from one to three degrees. Such slopes often extend for a distance of from 5 to 10 miles from the base of the hills bounding the plains, the difference in level between the top and the bottom of the incline being frequently from 1,000 to 2,000 feet or even more. What proportion of this depth consists of detritus it is impossible to say, but depth of the deposit must be great, because hills of solid rock but rarely emerge from it. The greater part of such slopes consists of sand and pebbles, the latter more or less angular and mixed with large blocks, all derived from the adjacent hills. . . . Fragments 2 or 3 feet in diameter are not uncommon, even at a distance of a mile or two from the base of the hills; but I only observed them near places where small streams issue from the higher ranges. At such spots the gravel deposits are naturally very often raised into a fan-shaped slope. Such a phenomenon is common enough in all countries, and so are strong slopes at the base of steep hills; but the peculiar- ity of these slopes in Persia consists in their great breadth, and in the enormous mass of detrital deposits which they contain. From many of the desert plains of Persia valleys of great width extend far into the more hilly regions. These valleys have, along their sides, precisely such long slopes of gravel as I have jost described. The presence of a s.tream in the midst of the valley is by no means constant ; but occa- sionally small rivulets coming from the sides run for miles along the slopes without descending to the bottom of the valley, and are finally absorbed by the soil, if not exhausted by being diverted for irrigation. Even at great ele\-ations (p. 497) up to 9,000 feet, similar immense accumula- tions of loose material occur in many places, and the higher peaks and ranges rise out of them. Among certain of the higher mountains, for example, near Shiraz (p. 498), where the rainfall is greater than usual and the streams flow perennially, the \-alleys present quite a different appearance, being flat-floored and havino- no gravel slopes along the sides. The reason for this peculiarit}-, as Blanford infers, is that the perennial streams are able to carr>' away the waste that is brought into the valley, whereas, if the streams come to an end at the base of the hills, it is inevitable that the detritus which they carr\- should be deposited at once and fans should be built up indefinitely. Blanford describes many fine examples of superficial deposits, especially of gravel slopes, and there are numerous others which might be mentioned. A small but typical example is the basin of Tabas, 60 miles east of Birjand, among the mountains, at an elevation of about 4,000 feet. The center of the plain, which is about 15 miles in diameter, is composed of the finest silt, and as water is relatively abundant, most of it is cultivated. Outside the cultivated area is a broad rim of fine gravel, difficult of cultivation, but very useful to the traveler, as we found during the melting of one of the occasional winter snows. The center of the plain was so mudd>- and slipper)- that it was utterly impassable for camels, which are the most helpless of beasts of burden when removed from their proper en\-iron- 250 THE BASIN OF EASTERN PERSIA AND SISTAN. ment. On the fine gravel, however, they had no difficult)'. The junction between the gravel and the silt is ven' indefinite, and the two formations appear to merge into one another in many places. Elsewhere, however, the gravel lies over the silt, and we noted here and at Sistan that certain streams were engaged in the process of bringing small gravel and spreading it out in a smooth and ven,' thin sheet upon the silt. Outside the band of finer gravel, the borders of the plain of Tabas are formed of coarser gravel, which increases in size and in the angle of slope of the surface as the mountains are approached. On the ver)- edge the gravel becomes a mere mass of rough, angular fragments of all sizes up to a foot or more in diameter, and it is hard to say where the coalescing fans of the ba.sin deposit come to an end and the creep from the mountain slopes begins. The basin of Selabad, 60 miles southeast of Birjand, is of much tlie same character. The center of this basin is not occupied by fields, but b)- a salt playa 6 or 8 miles in diameter. On the edges of this are broad deposits of silt, some of which are cultivated. Outside of these are the usual gravel slopes. The surfaces of these tiresome, gently sloping expanses of gravel do not lie in one plane, as appears at first sight. Although they owe their origin to a sheet of w-a.ste which descends evenly from all parts of the mountains, this waste must first be gathered into valleys. Thus the immediate origin of the gravels which skirt the mountains is the innumerable fans which head in e\en- valley, large or small, and expand outward until they coalesce with their neighbors on either side and merge into the plain of silt at the lower end. Each fan, no matter how flat it may seem, is really part of a cone ; hence the union of many fans must fonn a series of low swells and faint hollows. In only one way can this rolling quality be brought to the notice of the eye, at least in the larger basins, without the aid of instru- ments of precision. This is well illustrated in the northern portion of the Desert of Despair. In looking across a piedmont slope at right angles to the mountains, it often happens that the lower half of some far-away mountain is hidden from view by the seemingly level plain as by a hill. For a mile, or even five, the moun- tain may be approached without apparent change in its appearance, but at last, slowly and almost imperceptibly, the whole of the distant blue mass is exposed to view, and one realizes that he has reached the arch of a huge flat cone of detritus. Beyond the arch the mountain again half disappears, and then reappears on the next cone, and so on indefinitely. The traveler feels that he is traversing a smooth plain, although his reason tells him that he is crossing a series of broad swells made by the coalescing of great fan-shaped cones of detritus. His aneroid may show that the arch of a fan is one or two hundred feet higher than the hollows on either side. Almost ever)- writer on Persia speaks of the astonishing aljundance of gravel. The largest gravel plain which I saw was on the northwestern border of tlie lake of Sistan. From Beudun to Bering a smooth plain extends toward the southeast with a uniform slope so gentle that in 30 miles it amounts to but little more than 800 feet. From mountains to lake the plain is composed of pebbles of dark lime- stone and slate, coarse and angular near the mountains, well-rounded and small near the lake. It is hard to understand how gravel, even though fine-grained, can PERSIA AS AN EXAMPLE OF AN ARID COUNTRY. 25I be transported and spread in a sheet on so gentle a slope. East of Sistan the won- der becomes greater. According to Colonel McIVIahon, the drear}- expanse of the Dasht-i-Margo extends eastward 150 miles without change and without interniption from the top of the bluffs of Sistan to the first mountain, Malik-Dokhand in Balu- chistan. In tliis distance the plain rises 2,500 feet — less than 17 feet permile — and yet gravel has been smoothly distributed ever\-\vhere. It is noteworth}- that in the driest regions the accumulation of gravel is most extensive, provided the relief of the neighboring mountains is great. Proceeding now from the coarser to the finer deposits, we find that the center of each basin usually holds a salt lake or playa, bordered by an area of fine silts. Plajas and salt lakes are so abundant and various that the Persians have different names for different sorts. The names are used loosely and often overlap, but there seems to be some system. Thus " darya " signifies simply a lake or any large body of water ; " hamun," which is often translated " swamp," is used for a body of water which is partly open and partly filled with reeds ; next comes " nemeksar," a salt lake which is dry part of the year, but contains water during the rainy season, and, on dr\ing up, deposits salt which can be used commercially. Still drier than the nemeksar is the " kavir," a salt playa or swamp which may sometimes be covered with water for a brief period, but never fonns a real lake in which salt of economic value is deposited. Its deposits are always mixed somewhat with sand and silt. The Persian naturally looks upon the utilitarian side of physiography, but his classi- fication is exact enough to be of scientific \-alue. In all these fonns of lake, swamp, or playa the deposits which are not composed of salt present much the same appearance, being usually fine-grained saline clays or silts. OLD AGB. In the absence of obser\'ational knowledge of any countn,- which has grown old under arid conditions, we are obliged to fall back upon deduction in order to dis- cover the ultimate fate of Persia if the present conditions of climate and elevation remain unchanged. In youth and maturity the elevation of the floors of the basins above sea-level is of small importance. In old age it plays an important part. If the floor of a basin is below the level that would be occupied by a peneplain at the same distance from the sea, it will never be affected by aqueous erosion and, unless otherwise influenced, will preserve the fonns due to deposition as long as the continent continues to exist. If the center of the basin is considerably above sea- level, on the other hand, the basin fonn and the features due to deposition will eventually disappear. In ever\- region where there is any aqueous erosion the divides between different drainage areas must shift continually until the slope on the two sides is equal. In a basin region such a state of equilibrium can never be attained so long as the streams on one side flow to the ocean and those on the other to a basin ; for the local base-level of the basin rises indefinitely by reason of depo- sition, and the slope of the streams flowing inward is continually diminished. The ocean base-level, on the contrary-, remains fixed, and the slope of the streams reach- ing it is diminished only by the lowering of the divide which affects the streams on both sides to an equal extent. Accordingly the ocean streams will always have a slightly perhaps imperceptibly, steeper slope than their opponents, and the di\-ide 252 THE BASIN OF EASTERN PERSIA AND SISTAN. must shift inward until the center of the basin is reached and the basin is destroyed. Tliis must happen in ever)- country, pro\ided the streams are strong enough to reach the sea. The divide, in its migration, will come into regions deeply buried in gravel and silt, but the streams nuist cut through this in time and reach bed rock. When this happens the topography will lose the characteristic forms due to deposition and assume fonns detennined by erosion along lines indicated by rock structure and rock texture. The whole country will doubtless be deeply shrouded in gravel, the residue of decomposition left after the wind has swept away the finer material, l)ut the main topographic forms will be determined by the character of the rocks, and will so con- tinue until all relief disappears. Therefore, if the center of a basin region is suffi- cientlv elevated above the sea, and if the rainfall is great enough so that some streams reach the sea, the basin character will eventually be destroyed, the major forms due to deposition will disappear, and in old age the arid countrj- will present a topography similar to that of a moist countr}-. The chief difference will be that the moist region will be reduced to a peneplain deeply shrouded in fine soil and densely covered with vegetation, while the arid countrj- will be reduced to a peneplain deeply shrouded in wind-swept gravel and almost void of vegetation. Under still drier conditions another state of affairs is possible in old age. Sup- pose that the countr)- is so arid that no stream is able to reach the sea. The divides will migrate until the streams on the two sides have the same grade, and then will sink steadily, though exceedingly slowly, in one position. While this is in progress, the rainfall will still further diminish becau.se of the lowering of the mountains, the streams will grow even shorter, and the heads of the gravel fans will rise nearl)- or quite to the divides. At last there will come a time when the land forms produced by deposition will dominate the topography of practically the whole country. Ckavel fans, e.xtinct playas, and deserts will everywhere prevail, and the little rain which falls will so soon be evaporated or sink into the ever-deepening gravel that running streams will be practically unknown. Whatever transportation of solid matter toward the sea takes place by means of water will be almost infinites- imally small, and the whole result will be an immeasurably .slow melting away of the country which will not materially affect the surface. If this were the end we might conclude that in an extremely arid countiy all the topographic forms of old age are due to deposition, with the single exception of the divides, which to a certain extent survive as the last remnant of forms due to erosion. There is still one factor, however, which we have disregarded. As the power of aqueous erosion decreases that of rcolian erosion increases. In a countr)- which had reached the stage of old age which has just been described, the wind would pla)- an exceedingly important part. It would comminute and strip off the gravels on the surface, and then would begin to erode the underlying rock. The forms produced would be ver)- different from those of aqueous erosion in detail, but they would follow the same guidance of rock-structure and rock-texture. Thus in extreme old age the driest country must be reduced to a peneplain, parts of which may lie below sea-le\-el where the strata are ver)- soft, and all of which will follow the lines of the rock structure. The surface of the peneplain will be strewn with fragments of waste which will increase in size in proportion to the aridity. THE INFLUENCE OF CHANGES OF CLIMATE. 253 SUMMARY. Ill earl}- \oiitli the main forms of Persia probably differed but little from those of a moist coiiiitn.-. There was more nakedness, roughness, and sharpness, but this was confined to the minor details. From }-outh onward, however, through maturity the land forms of Persia increasingly diverge from the fonns of moister regions. Those of the latter are shaped by erosion ; those of Persia largely by deposition. In the one case basins are destroyed ; in the other the}- are preserved. The di\-er- geuce between the two types is at a maximum during mid-maturity, when, in a moist country such as the southern Appalachian region of the United States, inclosed basins have wholly disappeared, a subsequent drainage follows implicitly the lines of rock structure, and the slopes of the mountains are completely graded ; while in an arid countr}-, such as Eastern Persia, inclosed basins are the rule. The drainage is largely interfered with by immense areas of deposition which have no connection with the underlying rocks, and the slopes of even the lower mountains are rough and naked. From mid-maturity onward the main topographic forms of moist and of arid lands again approach one another somewhat, until in old age both are reduced to peneplains. If the wind is active, however, the arid peneplain will continue to develop and ma\- be eroded below sea-level. PERSIA AS AN EXAMPLE OF THE INFLUEN-CE OF CHANGES OF CLIMATE. Although as a whole the basin deposits of Eastern Persia indicate the long prevalence of an arid climate, there are certain phenomena which suggest a depart- ure from the present condition during relatively recent times. These consist, in the first place, of fine deposits of silt and clay which seem to be of lacustrine or playa origin, although they lie in regions which are never inundated under the present climatic conditions. Associated with these are shore terraces of the kind which are usually characteristic of lakes. These are best explained bv supposing either that the rainfall of former times was greater than to-day, or that the climate was colder, evaporation was less, and a greater accumulation of water was possible in the basins. Another class of facts seems to have some connection with the lakes, but is by no means so well understood. Numerous valle\s in all parts of Eastern Persia contain a series of terraces ranging up to five in number, and closely similar to the terraces of Turkestan. Sometimes the terraces are cut partly in rock and partlv in stream-laid gravel, sometimes wholh- in stream-laid gravel, and sometimes in stream- laid gravel which lies with a slight unconfonnity upon finer deposits of silt. Such unconformities are common on the edges of the ancient lakes, and in almost ever}- case coarse material lies above and finer material below, while the transition in the reverse order from coarse below to fine above seems to be gradual, without au}- sudden change. As the terraces and the associated phenomena represent the most recent physiographic changes which have taken place in Persia, it is not impossible that some of them originated since the advent of man, and they must be carefully explained. 254 THE nASIN OF EASTERN PERSIA AND SISTAN. THEORIES OF TERRACE FORMATION. Tliere are three generally accepted theories of terrace fonnation. ( i ) The best- known theory explains terraces as the resnlt of tectonic movements of the earth's crnst. The nplift of a given region accelerates the streams and causes them to deepen their channels. A period of rest allows the streams to cnt down to grade and to broaden their flood-plains. A repetition of this process produces terraces, provided the broadening of the flood-plains during each successive period of rest is less tlian during the preceding period. For brevity I shall refer to this as the tectonic theory- of terrace formation. (2) A second theony- explains a large number of ter- races as due to the growth of stream-laid deposits in the valleys downstream from the foot of glaciers during successive glacial epochs and the dissection of the deposits by the streams during iuterglacial epochs. (3) Other terraces have been explained by Davis (d) as the result of the normal swinging of rivers in alluvial deposits during a single phase of downcutting. Under this supposition a river cuts laterally until it reaches the rock wall of the valley, where it is stopped by the rock. At its next swing in the same direction the stream is at a lower level, and, because of the narrowing of the valley downward in vertical section, reaches the valley wall before swinging so far as before. Thus it is not able to cut so far lateral!)-, and a terrace is fonned. (4) In addition to these three theories there is a fourth, which has been but little discussed. It has been outlined in the preceding report on Txirkestan, where the conclusion is reached that the terraces of that country are due to the alternations of climate which occurred during the glacial period in regions where no glaciation took place. I shall refer to this as the climatic theorj' of terrace fonnation. Of the four theories mentioned, the second and third can not possibly appl\- to Eastern Persia, for no trace of glaciation has been detected there, and the terraces frequently continue for many miles without approaching the rock walls of their valleys. The explanation of the Persian terraces seems to lie either in the first or the fourth theory — the tectonic or the climatic. In the following pages the terraces of Eastern Persia and the neighboring portion of Transcaspia are described and an attempt is made to ascertain which tlieor}- best fits the facts. To avoid confusion I shall use the terms "fluvial" and "interfluvial,"' or "lacustral" and " interlacustral," when speaking of the climatic equivalent of the glacial period in non-glacial regions. These terms must not be understood as bearing any implication as to the cause of the glacial period. Either an increase in cold or an increase in precipitation would cause the lengthening of the rivers and the expansion of the lakes. Hence the climatic equivalent of a glacial epoch is appropriately termed a fluvial epoch when we are considering river action, and a lacustral epoch when we are considering lake action. EXAMPLES OF TERRACES. THB NORTHERN SLOPE OF KOPET DAGH. In his report on Transcaspia Professor Davis has described the terraces of Kizil Arvat, at the western end of the Kopet range, 140 miles northwest of Askhabad, and also those of the portion of Kopet Dagh immediately to the west and south EXAMPLES OF TERRACES. 255 of Askhabad. In both these regions there were well-marked series of terraces, indicating a succession of decreasingly severe impulses toward valley deepening. Whether the cause of these terraces was to be found in cnistal movements or in changes of climate could not be determined becau.se of the small number of exam- ples, either cause seeming to be competent to explain all the phenomena. Farther east along the northeni slope of Kopet Dagh the same state of affairs continues indefinitely. At Anau, 6 miles east of Askhabad, a small stream breaks through a gorge in the front range of Kopet Dagh and debouches upon the piedmont plain, where its waters are diverted for irrigation. In its upper course the Anau stream flows northwestward through a broad valley of soft strata, which were depressed to their present level by the fault which uplifted the small Anau ridge on the northeast side of the valley. This Anau ridge appears to be a fault block of the same sort as that of Suru-Muzdar, which lies on the southwestern side of the valley and has been described b}- Professor Davis. In both of these parallel blocks the south- west side presents a precipitous escarpment, the battered successor of the original fault scarp, while the northeastern face presents a smoothly-graded slope in which are incised the deep trenches of small consequent streams. In the Suni-Muzdar Oi 6=course of brook ; c, default ; l^liniestone ; 2=conglomerate ; 3=-red silt ; 4=gravel ; 5— soft Tertiary fonnation. Fig. 136. — North and south section along the Anau Brook, across the Anau fauh block. Dash lines indicate terraces. block, so far as could be judged from a distance, the back slope appears to be wholly stnictural, following the bedding of the hard Cretaceous limestone. In the Anau block, on the other hand, the tipper part of the back slope is determined by the structure of the limestone, while the lower part is quite independent of structure and truncates the underhing warped Tertiary strata (fig. 156). Where the Anau stream turns to the north and passes out of the trough between the two fault blocks it has cut a deep gorge in the Anau block. The sides of this gorge are steep, but even at the narrowest point the bottom is flat-floored and has a width of several hundred feet, so that although the gorge is young there nuist ne\erthe- less have been a considerable lapse of time since its cutting was begun, and even since it was cut to its present level and the work of broadening the bottom began. The Anau gorge is important becau.se of the terraces which it contains. As is seen in the cross-section (fig. 156) the stream, on leaving the soft strata south of the Anau fault block, first traverses a hard limestone forming the narrowest portion of the gorge, and then a coarse conglomerate, and lastly a red silt already described as like the silts of Kashgar and Bajistan. Overlying the conglomerate and silt, both of whicli ha\'e been warped and dip northward, extends a recent conglomerate or, 256 THE BASIN OF EASTERN PERSIA AND SISTAN. better, gravel, forniiiit:^ an unconsolidated sheet some 40 or 50 feet thick, which lies unconfoTuiably on the beveled edges of the other strata and shows almost no sign of warping. It seems probable, howe\-er, that the gra\el sheet has been uplifted and tilted somewhat, and that it rejiresents the old piedmont deposit of a time pre- vious to the faulting and ui)lift of the Anau and Suru-Muzdar blocks. On the east this conglomerate or, belter, gravel, forms a smooth though slojjing plain, in which are incised young valleys ; on the west it has been dissected into low, rolling hills. Thus far there can be but little question as to the true nature and origin of the phenomena of the gorge ; it is when we come to the terraces that the difficidty begins. In its more open portions to the north of the hard limestone the sides of the gorge are marked by well-defined gravel terraces to the number of five, which gradually converge downstream until the}', as well as the upper grade plain, merge into the general slope of the present piedmont plain in the vicinity of Anau, where the stream comes to an end. The heights of the terraces above the stream, as measured at a point well within the gorge a little below the so-called "Old Mills," are approximately as follows : Keet. First terrace, narrow and insignificant 3 Second terrace, rather broad and strong 6 Third terrace, broad plain of main valley floor 20 Fourth terrace, narrow, often missing 50 Fifth terrace, broad and flat 100 Grade plain, uplifted piedmont deposit 300 The whole number of terraces is not always present, sometimes one and some- times another being undercut ; nor does it appear as though they all merged into the plain at the same point. If all the terraces were cut in the solid rock, and came to an end in the Anau fault block, it would be easy to explain them as the product of the same faulting which produced the block and which uplifted the old piedmont plain. As a matter of fact, however, the lower terraces at least, so far as their structure could be made out, seem to be composed entirely of stream-laid gravel. In other words, the gorge was cut to nearly its present form and then was subjected to a series of changes by which it was first filled with gravel and then cut out again. Moreover, although the terraces disappear in the narrowest portion of the gorge, three of them reappear in the more open jxjrtion of the valley farther upstream — another evidence that the younger ones are of later date than the gorge. The importance of the relative ages of the gorge and the terraces lies in the fact that the fault which caused the cutting of the gorge represents the last mo\-ement of uplift of which we have any unmis- takable record. It is not impo.ssible that the terraces are due to earth movements of a kind which first caused deposition and then erosion, this alternation being repeated as many times as there are separate gravel deposits, an unknown quantity which may number from one to five. The Anau terraces, like those described by Professor Davis, are uusatisfacton,-, because, so far as can be seen, thej- may be either tectonic or climatic in origin. At Anau, and elsewhere along the base of the moimtains as far as Dushak, where the railroad turns to the northeast, the hasty view of the country- obtained EXAMPLES OF TERRACES. 257 from passing trains shows that ahnost universally the " ateck," or " skirt " of the mountains, as the Turkomans tenn the piedmont slopes, has been subjected to a slight dissection. The numerous coalescent fans are intersected by small dn,- valleys, the peculiar feature of which is that they are not fresh, but are everywhere grassed over, while the sides are reduced to a very gentle angle and the bottoms appear to be half filled with sediment. They are certainly not channels which are now being eroded, and they seem to extend farther than the farthest floods of to-day. It is possible that they belong to a rather recent time when the streams flowed farther out into the desert than they do to-day. The largest stream of the district is at Lutfabad, where the railroad crosses the lower waters of the stream whose terraced upper portions have been described by Professor Da\ is. Here, where the stream spreads out upon its fan shortly before coming to an end, it is bordered by two distinct terraces. From Dusliak southeastward for 80 miles to Serakhs, at the northeastern corner of Persia, on the Heri Rud, or Tejen River, I traveled b}- caravan and was able to examine the countr\^ more closely. Few new features were seen, however. Near the mountains the fans are naturally more arched and more gravelly than farther out toward the plain. Curiously enough, the old stream channels do not take the form of depressions, but appear as incipient ridges topped with a belt of cobble stones, some of which are 6 or 8 inches in diameter. Apparently at some previous time the streams deposited cobbles along the floors of their channels. Since that time the fans have been so far degraded that the channels have disappeared and their floors have been converted into ridges. The present streams are incised below the plain to depths of from 10 to 15 feet, or even more. All that were seen were small dry channels, with the exception of the flowing streams at Meana. THE MURG-AB RIVER. Omitting for the present the Heri Rud (river), which comes from the interior of the Iran basin, one more stream must be described, which flows from the northern side of the mountains. The Murg-ab, i. e., Murg-water, rises in the Paropamisus Mountains in northwestern Afghanistan, and flows northward into the desert of Transcaspia, where it finally loses itself in the reed-beds of a swamp after watering the flat oasis of Merv. At Merv itself and throughout the oasis the main stream flows practically on the surface of the delta, although some of the irrigation canals are incised 10 or more feet Upstream, however, the delta is bounded by cliffs of silt, which gradually converge and grow higher until at the dam of Hindu Kush, 30 miles above Merv, the river flows in a well-defined valley. At the dam the sides of the river show two terraces, one of them 10 feet above the level of the water in June and the other 30 feet above that level. The banks of both terraces appear very young and freshly cut, as indeed they ought, since the lower is merely the border of the channel and the upper is occasionally undercut by the river when an unusually high flood causes the stream to overflow. It is interesting to note that the channel seems to be growing deeper at an appreciable rate. The dam is located just below the divergence of an old river channel which was abandoned something over a hundred years ago, and into which the new dam, completed about 1895, now 258 THE BASIN OF EASTERN PERSIA AND SISTAN. diverts a part of the river. According to Mr. Nikrashevich, superintendent of the dam, the inner terrace at the bottom of the old channel had a height of 2 feet before conditions were changed by the building of the dam, while the inner channel, where the stream to-day runs, has a depth of about 16 feet. That is, the bottom of the river to-day is 14 feet lower than it was at the time of the abandonment of the old channel a hundred years ago. Part of this difference, however, may be accounted for by filling of the latter subsequent to its abandonment. Since the building of the dam the river has so filled up its channel above the artificial obstruction that the lower terrace has entirely disappeared and the stream has no proper channel, but wanders this way and that over its own depo.sits. This wandering is causing the widening of the flood-plain, and there is great danger that in time a sudden change in the course of the main stream will cause it to cut into the banks close to the dam and finally to break a way around the end of the latter. Such a catastrophe took place at Sultan Bend, a few miles up the river, where a dam was built about 1890 and was abandoned a few years later. Retaining walls were built in all directions, but nothing could prevent the river from cutting laterally when it was prevented from accomplishing its normal work of vertical erosion. The material which is now being deposited by the Murg-ab seems to be the same as that which is exposed in the bluffs of the terraces. It consists of a very- fine clayey sand well stratified and with a consistency like loess. It stands for years in nearly perpendicular bluffs, and preserves the marks of the pick indefinitely. It is said that as far as Tash Kupri, nearly a hundred miles upstream, the same fine sandy deposit continues, and only at that place does it become gravelly. The terraces also continue far upstream. At Tash Kupri there are said to be two, one of them close to the river and the other 70 feet above it. At Sultan Bend, 15 miles above the dam at Hindu Kush, there are three terraces. At the top lies the great sand-covered alluvial plain, 70 feet above the river ; then comes a broad terrace co\'ered with tamarisk and other bushes, and hing about half as high ; and lastly there is a small young terrace only 10 feet above the water. Here, again, as in so many other cases, there is no positive indication as to whether the terracing is due to climatic or tectonic causes. There are archeological indications that the flow of the Murg-ab one or two thousand years ago was more abundant than at present, and it is not impossible that the decrease in the size of the stream is con- nected with the building of the lower terraces. THE HERI ROD. The Heri Rud, or Tejen River, as it is called after it enters Russian territory, when taken by itself is no more conclusive as to the cause of the terraces than are the other rivers. To be sure, it flows directly across the northern mountain rim of the basin of Iran, and thereby differs from the other streams which we have considered. If the terraces are due to an extensive uplift of Kopet Dagh and the Paropamisus, the main axis of that uplift must have passed directly athwart the Heri Rud not far from what is now the Afghan border, accelerating the lower or northern portion of the stream and retarding the upper portion. The process of terrace-making under such circumstances would differ materially from that in cases EXAMPLES OF TERRACES. 259 where the whole stream was tilted in one direction, but the resulting forms would be similar in appearance. They could be distinguished from climatic terraces only by means of a careful study of their height at many places and of the irrelatiou to uplifted areas and to the mountains along the course of the stream. There is, however, one respect in which the Heri Rud affords a valuable clue to the origin of the terraces. Closely associated with the river, and in one case forming part of its system, are some small lakes showing phenomena which it seems impossible to explain on any hypothesis except that of climatic change. If a study of these shall show the terraces of the Heri Rud to be of climatic origin, there is a strong presumption that the terraces of the neighboring streams are due to the same cause. In its lower course the Heri Rud closely resembles the Murg-ab. At Tejen it flows upon the surface of the plain and is also liable to the extraordinary- floods described in Profes.sor Davis's report. At Serakhs the cross-section is much like that of the Murg-ab at Hindu Kush, with the river flowing in a deep channel about 10 feet below what may be termed either a lower terrace or an elevated flood-plain, and with a second terrace 20 feet high rising to a broad alluvial plain. Fifty miles fiirther upstream, at Pul-i-Khatun, below the lower gorge, there are four terraces. The lower one is small, as usual ; the second forms a broad plain half a mile wide, on which is located a Russian military- post to guard the only bridge in this part of the countr)-; the third is narrow, though distinct; and the fourth is the rather flat tops of the surrounding hills of old alluvium. But little was seen of the 35 miles of the river between Pul-i-Khatun and Zulfagar (Zulfikar) at the northwestern comer of Afghanistan. Most of the way the ri\-er flows in a narrow gorge, and whatever terraces may have existed are naturally destroyed for the most part. Just south of Pul-i-Khatun, in a relativeh' open stretch, two were noted, composed of gravel which had clearly been brought in as a filling after the work of valley- making had reached practically its present stage. At Zulfagar, in the ancient lake basin of Zorabad, the valley of the Heri Rud again widens, and at once the number of terraces increases. In one side valley five terraces were noted cut in the ancient lake clays ; in two or three others the number is four, while in many cases there has been so much undercutting or change of some sort that onh- the minimum number of two is preser\-ed. Along the main ri\-er the terraces, where best preserved, number five, of which the first, tliird, and fifth are usually strong, while the second and fourth are weak or missing. Some 10 miles south of the Afghan boundary and a little upstream from the dam of Dat Mehemet Khan, a very significant section is .seen on the right bank of the river as one looks downstream from the cultivated fields east of Khatami, on the left side of tlie river (fig. 157). Here the gravel renniants of what seem to be the third and fourth ter- races, counting from below upward, are seen to lie on a slope of westward-dipping shales which must have been subjected to erosion. The\- indicate that before the formation of each terrace the valle\- must have been cut well below the level of that teixace, though not necessarily to the present depth, and then filled with gravel. This is not absolutely inconsistent with a tectonic origin of the terraces, but inas- much as this section lies close to what nuist have been the axis of any supptosed 26o THE BASIN OF EASTERN PERSIA AND SISTAN. uplift, it would demand that for the jiroduction of each individual terrace there must have been an uplift to cause dissection and a depression to cause deposition. If the terraces are of climatic origin no such complicated and highly specialized wavering of the earth's crust is required. Upstream from the Khitayi section the Heri Rud traverses a narrow limestone gorge through which there is at present no cara\an trail, and where, so far as could be seen, there are no terraces. Twenty-five miles farther south, at the mouth of the Jam River, where the valley again widens, terraces appear once more to the number of four, with the remnants of what seems to be a fifth farther back. They are cut in the brownish and reddish shales described previously and are characterized by a heavy stratum of gravel from 5 to 20 feet thick lying upon the soft shales or silts, unconfonnably as a rule. Owing to the softness of the material, all the terraces are very broad. Upstream the lower terrace grows continually wider, apparently A, B, and C=terraces of horizoutal gravel. D=tilted shale. E F^course of riTer from right to left. Fig. 137. — Terraces o( the Heri Rud, near Khatayi. View northeast across the river into Afghanistan. because the silts become softer, until, at the point where the Heri Rud turns from a westward to a northward course, it fonns a plain, 10 or even 20 miles wide, and the upper terraces are entirely consumed. THE LAKE OF KOGNEH NEMBKSAR. The salt lake of Kogneh is situated near the mouth of the Jam River, in the northwestern angle between that stream and the Heri Rud, close to where the latter passes out of the open region of terraces which has just been described (see fig. 158). The lake is of insignificant size, only a mile long from northwest to southeast, and three-quarters of a mile in the other direction. It has no outlet at any season. Wlien we saw it in December a small stream flowed into it from the northwest, and there was a little water in pools here and there. The amount of water maj' have been more than appeared at first sight, as the surface of the lake was covered with a sheet of salt, and the shores were composed of thick, black mud, so wet that it was impossible to approach the open water. On all sides except the northwest the lake EXAMPLES OF TERRACES. 261 is bounded by steep bluffs, 35 feet high, which on the north and northeast are com- posed of a rather solid fonnation which appears to be a portion of the half-lithified basin silts of Tertian*- age. On the southeast and south the bluff consists entirely of stream-laid gravel. On the northwest side, whence the lake receives its water supply, a plain, at first marshy, rises gently to the great basin plain of silt bordered by gravel, in which are located Kalagak and Turbat-i-vSlieik Jam. The rise from the lake to Kalagak, however, is not perfectly smooth, for beyond the marsh)- border it is broken by two small terraces, the lower of which is very slight, while the upper, perhaps 15 feet above the water-le\-el, is also slight, although it is clearh- marked. Around the lake itself, at the foot of the bluffs and about 10 feet above the water- level, is a beach which extends downward 4 or 5 feet. It may represent the extreme high-water level of to-da}-, although I could get no information on this point. It Fig. 1 58. — Sketch-map of Kogneh Lake and tKe Jam Basin. probably corresponds to the lower terrace. The bluff which surrounds the lake is very flat-topped and is unbroken except at one point on the southeast side, where there is a notch, broadly flat-floored and some 12 or 15 feet deep. This notch opens into the head of a well-defined valley which discharges to the Jam River, as shown in the sketch. It is evidently not occupied by water even during tlie highest floods, and there can be no doubt that it is an abandoned chamiel, representing a former higher stand of the lake. It probably corresponds to the upper of the two small terraces on the northwest, but the latter seemed to be lower than the notch, and as no exact measurements could be taken the matter must be left inisettled. The phenomena immediately about the lake indicate that the water must at various times have stood at three, or possibly four different le\-els. First, the le\-el of the top of 262 THE BASIN OF EASTERN PERSIA AND SISTAN. the gravel bluff; second, the level of the old outlet; third, the level of the upper terrace, although this may be the same as the old outlet ; and fourth, the level of the lower terrace and the beach which may be reached to-da}- in time of flood. At a little distance from the lake we find evidence of still other changes in the behavior of the water-courses. If the le\-el top of the gravel bluff south of the lake be followed northwestward, it will be found that it merges smoothly into the plain of Kalagak. In the plain the .streams have incised themselves to a depth of from 4 to 10 feet, in response apparently to the changes in lake level indicated by the little terraces. On the edges of the plain two terraces of quite a different kind present strong escarpments heavily capped with gravel. These correspond to the uppermost of the terraces of the Heri Rud, as appears by following them to the south, where tliey are well displayed. Along the Jam River seven terraces can be seen in certain places, but as two of them, near the bottom of the series, do not seem to be permanent, we shall consider them as adventitiotis and leave them out of account. The third terrace, counting the upper and oldest as the first, corresponds to the Kalagak plain and to the top of the bluff south of the lake. The fourth ter- race, that is, the one next to the bottom, if it be traced toward the lake, is found to coincide with the bottom of the old outlet. A little tributar}- of the Jam is now gnawing back into the soft gravel in which the fonner outlet is trenched, and will in time cut through the bluff and drain the lake. The fourth and fifth terraces along the Jam seem to correspond to the low terraces northwest of the lake and to the slight channeling of the Kalagak plain. The terraces along the Jam are strong while the others are weak, because the main ri\er was able to continually deepen its channel, wliile the lake furnished abut slightly changeable base-level and prevented its tributaries from cutting deeply. Turning now from a mere statement of facts to a consideration of causes, we must first sum up the historj' of the lake of Kogneh and the neighboring rivers. Originally an uninteiTupted stream must have flowed from Kalagak to Daniduo, where, after passing what is now the site of Kogneh Lake, it joined the Jam River, and the combined streams emptied into the Heri Rud. For some reason this whole river system was subjected to certain s}'stematic changes by wliich the streams were at first induced to dejxjsit abundant gravel and to wander widely from side to side. Then other conditions ensued under which the streams acted in exactly the opposite fashion and cut deeph- into their beds, carrying away much of the gravel, cutting even into the underlying rock and forming high terraces. Just how many such alternations took place we are unable to say, but there were at least two before the formation of Kogneh Lake. During the third time of gravel deposition and river wandering, the large Jam River deposited its load so rapidl}' across the mouth of the Kalagak stream that the latter could not keep an outlet clear. Thus a bar was formed across the mouth of the Kalagak \'alle)-, and behind this the brook spread out into the lake of Kogneh, finding an outlet to the main stream as best it could among the gravels of its bigger neighbors. Up to this point the history of the region is explicable either on the tectonic or the climatic theory ; from this time onward only the climatic theory seems competent to account for all the facts. EXAMPLES OF TERRACES. 263 When the third period of degradation and valley deepening set in, the volume of the streams, according to the tectonic theor\', was unaffected, and Kogneh Lake must have remained full. Supposing this to be the case, the lake continued to overflow to the Jam River throughout the third period of degradation and the fourth period of aggradation. At the beginning of the fourth period of degradation the flow of the Kalagak stream was somehow so diminished that the lake no longer flowed, and the al^andoned outlet was left at the level of the fourth terrace. The cause of the sudden desiccation of the lake, no marked change of climate being admitted, can only have been a diversion of some of the tributaries of the Kalagak brook. I saw no sign of any such diversion and it is not likely that it took place, but without detailed study of the region this can not be asserted positively. The last change in the lake, b}- which the lower terrace was fonned, will have to be explained by the same gratuitous assumption that a tributar\- of the Kalagak was again diverted, this time toward instead of away from the lake. It can not have been the same tributar\- as on the earlier occasion, because it only sufficed to half fill the lake. Lastly, this second tributary' must have been again diverted in order to bring the lake to its present condition. These changes must have taken place at the same time that the lower terraces were being formed along the Jam and the Heri Rud. It is possible to explain the phenomena of Kogneh Lake on the tectonic hypothesis, but it in\olves several assumptions for which there is no basis in facts of observation. The climatic hypothesis is simpler and involves no assumption beyond the facts of observation. At the end of the third period of aggradation, after the lake had been fonned, it is supposed that an interfluvial epoch ensued. The lake was desiccated to such a degree that it no longer overflowed ; the neighboring rivers eroded their channels and fonned a third tenace. Another change of climate with an increase in the size of the streams filled the lake to overflowing and caused the rivers to aggrade. When this came to an end the outlet had been cut to a depth which corresponded with the fourth terrace of the Jam, at which level the river was then flowing. Another interfluvial epoch left the lake empty and allowed the cutting of the fourth terrace. During the last fluvial epoch the increase in the volume of the streams was so moderate that the lake was not filled to overflowing, but merely to the level of the lower tenace, while in the river valleys slight deposits of gravel were laid down. Lasth-, the present dry epoch leaves the lake almost empty and has allowed the cutting of the lowest terrace along the streams. Theory- and fact seem to agree perfectly. If the climatic theor}- is the true explanation of the phenomena of Kogneh Lake, it must apply also to the terrace of the Heri Rud, for the two are inextricably connected. THE SALT LAKE OF PDL-IKHATCN. The other salt lake to which reference has been made lies back upon our line of march in Russian tenitory about 7 miles east of the gorge of the Heri Rud at Piil-i-Khattm. Shor Kul, or Salt Lake, as it is called, is realh- a plaja, a perfectly smooth expanse of salt-covered mud, 3 or 4 miles long and half as wide, and l>ing at a height of about 2,000 feet above the sea. It was so dn- in November, 1903, 264 THE BASIN OF EASTERN PERSIA AND SISTAN. that in ridino; almost across the middle of il my horse's hoofs sank in only abont an inch. The whole expanse is covered with a beautifnlly crystalline deposit of salt, thinner on the ed<^es and thicker toward the middle, where it crackles like snow nnder the horse's hoofs. The smooth playa floor is divided into broad concentric bands which grow successively whiter and more thickly covered with salt toward the center. They appear to mark stages to which the water had risen during the last season, and have the irregular boundaries characteristic of water which stands on an almost level surface. To the eye the surface of the playa seems perfectly level, Init there is a slight slope, as is shown by a beach marking the high-water level of spring. At the south end this can hardly be distinguished from the floor of the playa, but a mile or two farther north it lies distinctly 8 or 10 feet above the floor. No lacustrine terraces could be detected, although the bluffs, which are cut in soft sandstone, dipping gently northeastward, and which sometimes reach a height of a hundred feet, seem to have been imdercut during a former higher stand of the water. The tributary valleys, however, show terraces to the number of three, cut partly in rock and partly in a filling of gravel. Away from the lake these gradually die out in the course of a few miles. They might easily be due to an intermittent warping by which the basin was deepened, although that would demand a rather complex system of movements by which a minor basin warping should be superposed upon the main warping demanded for the Heri Rud. A climatic origin is simpler, but the terraces are too poorly developed to be of great importance. NKMEKSAR OR THE PLAYA OF KHAP. Beyond the great northward bend of the Heri Rud, in the southward con- tinuation of the Afghan depression, the playa of Khaf — the Nemeksar par excellence — and its basin continue the terrace phenomena of the more northern districts, though the maxinnnn number of terraces is less. At the northeasten comer of the basin we passed three valleys, all of which show two strong terraces of the usual type, with heavy gravel beds covering the horizontal portions and with the vertical portions cut partly in the gravel and parti}- in the underljing rock. Besides these there were two minor terraces, scarcely worth mentioning, one between the two strong ones and one below. In the higher valleys of the pass near Chani Well, 8 or 10 miles north of the northeast corner of the playa, a phenomenon was noticed which is rather connnon in the mountains of this part of the world. The steeper valleys are filled with coarse gravel firmly consolidated b\- a calcareous cement, and now dissected into rude terraces. The deposit is closel)' analogous to the gravel of the ordinary terraces, but diflfers in being found in very steep ungraded valleys and in being well consolidated. Apparently these two features belong together, since only a well- consolidated deposit could retain its position under present conditions on so steep a slope. The gravel and terraces appear to be due to changes of climate, since they are found in ungraded valleys which would be wholly uninfluenced by any movement of uplift or warping which did not directly affect their own grade. It is highly improbable that earth movements, detennined as they must be by broadly acting and largely subterranean causes, should so adjust themselves as to accelerate all the EXAMPLES OF TERRACES. 265 chief ungraded streams of several neighboring mountain ridges. Yet such must necessarily be the case, if the gravels and their terracing are due to a tectonic cause. The most probable explanation is that they occur in valleys which are ordinarily ungraded and hence subject to erosion, but which became graded during one of the fluvial epochs, perhaps not the latest, when the climate was so altered that even these valleys assumed a graded condition and were floored with flood-plains of gravel. The Nemeksar, or playa of Khaf, is a broad, almost waterlesss expanse of salt, much like the Pul-i-Khatun salt lake. In the late winter it is said to be entirely covered with water, although in mid-December we saw but a few detached bits of open water and were able to ride out nearly a mile before the nmd became dis- agreeably deep. On the northern edge of the playa, where high mountains rise within a few miles, huge fans of coarse, angular gravel temiinate close to the edge of the playa floor. Where they approach this most nearly they end in a distinct bluff", which is from 6 to 10 feet high and has its base 10 or 12 feet above the edge of the area that seems now to be subject to inundation. Between this latter limit and the foot of the little bluff" there is either no gravel or else a little very fine grit that has been brought in recently. The greater part of the fonnation here is a very fine silt, crusted thickly with salt. Where the fans do not extend as far as the line at the base of the bluff's, they die out gradually and irregularh- on a deposit of silt of the kind just described. In their upper courses these fans are dissected by chan- nels which at first grow deeper until they reach a maximum of 12 or 15 feet near the middle of the fans, and then decrease toward the playa. They appear to be channels cut during a fluvial epoch through a zone of maximum deposition fonned at a previous time of greater desiccation. The phenomena along the edge of the playa seem to indicate a somewhat higher stand of the water at no ven,- distant day. The high-water level of the present is indicated by an ill-defined beach a few feet below the base of the little bluflfs. Along the east side of the playa, as to the north, the main tributary valleys show two strong terraces which sometimes reach a combined height of 100 feet. They are of the usual t\pe, deeply covered with gravel. Where the formations surrounding the lake consist of soft Tertiary fonnations, there is some indication of ancient undercutting by the waves at higher levels. This feature is much better shown in the playa of Kulberenj, which lies in the Khaf basin a little to the south of the main playa. KDLBERENJ. At Kulberenj the whole playa is surrounded by two strong lacustrine terraces, one of which rises from 20 to 25 feet above the pla^a floor, and the other over 50. Below these there is in places a faint third terrace which would be too indefinite to mention if it were not that in other places similar traces of a last faint terrace-making epoch are evident. The two larger terraces consist of fine silt, on which is a cover of gravel 4 or 5 feet thick. Whether or not the silts are the deposits of an ancient lake of great size is not certain, although it is probable. The cutting of tlie terraces is clearly the work of three diff"ereut lakes, or of one lake working at three diff"erent levels. Naturally the tributary valleys are terraced to correspond to the lake. The phenomena of Kulberenj, Khaf, Pul-i-Khatun, and Shor Kul in Chinese Turkestan (see the report on Turkestan), all agree in showing that two or three times in 266 THE BASIN OF EASTERN PERSIA AND SISTAN. the recent past the lakes of Central and Western Asia have been more extensive than at present. The length of the epochs of high water was so short that no beaches or bluffs were cut upon hard rocks, although very distinct ones were cut in soft silts and gravels. In the lake of Kogneh, al.so, three probable periods of high water are indicated, and these are seen to be connected with ri\'er terraces of apparently the same date, and also with older ones. TERRACES AMONG THE MOUNTAINS FROM MESHED TO BIRJAND. F'rom the basin of Khaf our route led westward into the mountains to the east of Birjand, thence southeastward to Sistan, and finally back by another route north- westward to Meshed. Sistan is so important that it will be reserved for fuller treatment later. The mountains from the border of the Sistan basin, near Birjand, Fig. 159. — A slightly terraced Valley in the Mountains of Binalud Kuh, 30 miles north o( Turbat-i- Haideri, March 3. 1904. to the vicinity of Binalud Kuh, near Meshed, present so many features in common and withal so few of special importance, that they may be described in general terms without the tedium of particulars. As a rule, the parts of the mountainous districts of which the traveler in Persia sees most are the areas of deposition, the basins. In these it is not to be expected that terraces either of tectonic or climatic origin should be found, for the streams oftentimes come to an end in gravel, even though the form of the mountains round about shows that they might find ready outlet from the basins, as they probably have done in the past, if only they were provided with sufficient water. A significant feature of the basins is that almost universally gravel is encroaching upon finer sediments of a silt)- or sandy character. Wherever valle\s were seen in which water sometimes flows, they were found to be terraced almost without exception. The terraces are for the most part cut in EXAMPLES OF TERRACES. 267 a valley filling of gravel and are of small size. In many places they number but one, although farther north, around Turbat-i-Haideri, and among the mountains south of Meshed, two was the usual number. Most of the valleys in which the terraces were found drain either to the Heri Rud or to the Khaf playa, or at least belong to the systems of which the river and the playa are the final gathering- grounds. If the tributaries all reached the main streams it would be fair to infer that the diminutive terraces of the branches might be the reflection of the large terraces of the trunks, and were possibh' due to a cause acting at some distant point downstream. Inasmuch, however, as many of the branches never reach the trunks at any time, and as some of them are separated from the tnmks by ungraded stretches over which the influence of a downstream displacement would not be felt, it becomes almost necessary to refer these minor terraces to some local cause. If this is done, crustal movements are out of the question, since an impossible com- plexity and conformit)- with the minor surface features would be required. The only other possible explanation seems to be climatic change. THE TERRACES ON THE BORDERS OF THE DASHT-I-LUT. Along the borders of the Dasht-i-Lut, where the streams run with greater strength than they do among the gra\-el-clogged uplands, there is again a considera- ble development of terraces. In the valley of Haji Hussein Beg, a day's journey northwest of Birjand on the road to Tun, there are four good ter- races of the old familiar type, gravel, more or less cemented by calcite, above, and rock below (fig. 160). These terraces are highest along the steeper part of the stream's course, and die out as it approaches the smooth salt playa of Mehemetabad. There- fore they can not be due to any change in the playa whereby it became a lake. Indeed such a change would be impossible, since if the water of the playa rose ever so little it would overflow to the Dasht-i-Lut, and the playa could not be pennanenth- cov- ered with water unless the whole of Central Persia were converted into a vast lake. The terraces of Haji Hussein Beg may be due to warping which, for some peculiar reason, assumed such a form as to produce the same number and sort of terraces here in this detached locality which it had produced at approximately the same time in a score of other distant places. Or these terraces may be due to climatic changes, in which case their likeness to those of other regions is a necessary part of the theorj-. From Mehemetabad nearly to Bajistan, 35 miles north of Tun, there are no good series of terraces, and the scenery is much like that of the mountains to the east — gravel fans, buried mountains, and valleys with a single or occasionally a double terrace. At Bajistan three small valleys come together, each of which has one terrace cut in stratified gravel and brown silt. The town lies on what seems to be an older terrace, which has been half-buried by the later deposit of gravel, in Fig. 160. — Terraces in the Valley of Haji Hussein Beg in the Chahak Basin. 268 THE BASIN OF EASTERN PERSIA AND SISTAN. which tlie youn<(cr terraces are cut (fig. i6i). This is a good illustration of the way in which older terraces disappear, and explains why, in regions of gravel deposition, it frequently hapi)ens that only one terrace exists where we should expect to find more. The upper terrace at Bajistan consists of fine silt with a cover of gravel from I to 3 feet thick. It is the same phenomenon of gravel lying with a slight unconformity on fine silt, which is so noticeable throughout the whole of Central Asia from Kashgar to Sistan. On the tectonic hj'pothesis it can only be explained by supposing that the times of the deposition of the valley fillings lasted so long that the processes of erosion and weathering reduced the slopes of the mountains to a well-graded condition, which allowed them to furnish the streams with nothing but finely comminuted detritus. Times of uplift then ensued and at first caused Fig. 161. — The Town of Bajistan, loolcing east. In the Middle Foreground the Fields are Terraced (or Cultivation. In the immediate foreground lies a fluviatile terrace cut in silt and gravel. rapid erosion and a flooding of the valleys with gravel. Soon, however, the accumulations upon the graded slopes were all washed away, and the streams relied merely upon the products of contemporary weathering, which naturally furnished a much lighter load than the sudden carrying away of the accumulated product of many years' weathering. When the streams were thus more lightly loaded, they at once began to deepen their channels and form the terraces. Such an explanation is quite possible in the case of a single terrace, but it fails entirely when we come to two or more. If the interval between the fonnation of two successive terraces was so long as to allow the mountain slopes to be reduced from an ungraded to a graded condition, it is inconceivable that so slight a thing as an unconsolidated terrace should be preserved from one cycle to the next. EXAMPLES OF TERRACES. 269 According to the climatic hj-pothesis this difficulty disappears. During a fluvial epoch a decrease in evaporation or, still more, an increase in precipitation, would cause ungraded mountain slopes to become graded and covered with vegetation. The material washed down from such graded slopes and deposited in the valleys and plains would be relatively fine, whether it happened to be deposited in valley bottoms, in playas, or in lakes. When an interfluvial epoch ensued, vegetation would become scarce, floods would be more frequent and violent, and it would be but a short time before the slopes would assume their present ungraded condition. During this process the streams would at first be heavily loaded with the products of previous weathering, which they would deposit in widespread beds of gravel ; but ere long the supply would fail, and the streams would begin to deepen their channels and fonn terraces. This process might be repeated a number of times in rapid succession and thus a series of terraces would be formed. In parts of its flood-plain where a stream happened to be flowing at the time of a change from wet to dry conditions, the transi- tion from silt to gravel would be gradual and there would be no unconformity. Elsewhere the change would be marked by a sharp unconfonnity. Both of these conditions are found, but, as might be expected, unconformability is the rule. At the northeastern end of the basin of Bajistan, not far from the city of Turbat-i-Haideri, there are again four terraces, which must be due to a highly specialized warping of that particular basin, unless they are due to changes of I climate. The tops of the red- ~/^^\k dish silts, previously described, / / /^^^^^^^^9^^^^^^9=aa /fi2332E923S| are beveled by an old grade plain y/ / / y/ / / / /^'^ / / / / covered with from 5 to 15 feet of / / / /////////A gravel (fig. 162). Below this are Fig. 162. — Terraces at the Northeastern Comer of the Bajistan traces of a SCCOnd grade plain forming a second terrace which is almost consumed. At the base of the second terrace lies the broad plain of Bajistan, in which are cut two more terraces. There are thus four gravel-covered terraces sepa- rated into two groups. The same phenomenon is noticeable at Kogneh Lake and elsewhere. There seems to have been a long interval between the formation of two groups of terraces. The fact that this division is observed in widely separated places makes it probable that the cause of the terracing was of such widespread appli- cation as to affect enormous areas in precisely the same wa3^ This would be true of climate, but not of warping. SUMMARY. The part of Central Asia touched upon in this report and in the preceding report on Turkestan embraces 22 degrees of longitude and 12 degrees of latitude in the heart of the arid portion of the continent. Between the extreme limits of Kizil Arvat on the west and Issik Kul Lake on the east the distance is i,2CX) miles, while from north to south tlie distance is 800 miles. Throughout this large area, wherever young or mature mountains have been observed, the valleys contain terraces composed in whole or in part of gravel which must have been brought into them after they had reached nearly their present condition. 270 THE BASIN OF EASTERN PERSIA AND SISTAN. There are two hypotheses in explanation of the terraces — either the terraces are due to warping of the earth's cnist or they are due to the changes of climate which in colder regions caused the successive epochs of the glacial period. The terraces of each valley, taken by themselves, can be explained on the first of these theories as due to warping of the earth's crust. Such warping is essentially a local manifestation. The force which produces it may act simidtaucously over large areas, but the manner of manifestation is almost sure to varj' in details from place to place. Moreover, the force is an internal agency, and its manifestations can not be expected to coincide universally with such puny surface features as indi- vidual \-alle\s. When we examine the scores of valleys in which terraces have been noticed, it appears that the cause of the terraces has acted in just the way that tectonic forces can not act. The same phenomena occur everywhere with the same details as to the number of terraces, the method of filling and then re-e.\cavating the valleys, and the grouping of the successive changes. The incidence of the cause, moreover, must be taken to be that of an exterior, not an interior agency, because it has so acted as to produce the same effect upon all similar external features, whether they be remote from one another or whether they be closely and intricately interlocked. The more broadly the terraces are viewed the more unlikely does it become that they are the product of warping. The theory of climatic changes is of directly the opposite character in these respects, and seems to fit all the facts. It is not local, but almost universal in its application, since a change of climate in one place implies a corresponding change in other places. In a region such as we are discussing the details of climatic change, and hence the manifestation of those changes, would be almost identical everywhere. In the ne.xt place, climate is external in its origin, and so may be expected to adapt itself to the minute details of mountain and valley, and to produce the same effect upon all similar parts, whether they be remote or whether they be closely interlocked. In addition to these more general reasons for adopting the climatic rather than the tectonic theory of the origin of the terraces, there are others of a more specific character. At the heads of some of the valleys are old moraines, whose relation to the terraces proves that the two forms were in process of constniction at the same time. At the lower ends of certain valleys are inclosed lakes whose old shorelines show that while the terraces in the suiTounding valleys were being formed the lakes were subject to pronounced changes of level. One such lake is so closely connected with the terraces of the Heri Rud as to make it almost certain that the changes in the lake took place simultaneously with the terracing of the river. Both moraines and ancient shorelines are well known to indicate changes of climate. It is highly improbable that at the very time when climatic changes were taking place and were producing certain sets of fluviatile terraces any other agency should be at work which would produce the same type of terraces in almost the same region. Still another reason for accepting the climatic theory is that it alone seems competent to explain the habitual superposition of coarser deposits upon finer deposits in the filling of the valley bottoms. Lastly, the phenomena of Eastern Persia agree exactly with what we should theoretically expect to find if the climatic changes of the glacial period TERRACES IN TURKEY. ZJl extended to that country, and if those changes are competent to produce recognizable physiographic forms. The cause of the abundant terraces of Western Asia demands much further investigation, but it is at least a fair working hypothesis that the terraces are due to a series of climatic oscillations, and that those oscillations were contemporaneous with the successive epochs which in other lands composed the glacial period. If this theory proves worthy of acceptation it will probably furnish the necessary clue to the elucidation of the recent physical histor)- of the Caspian basin and of other parts of the earth's surface immediately before and perhaps after the advent of man. TERRACES IN TURKEY. If the conclusions which have been reached in the preceding pages of this report are correct, terraces of climatic origin ought to jircserve a record of some of the epochs of the glacial period in other parts of the world, especially where the conditions resemble those of Persia, that is, among unglaciated mountains in the stages ot youth and early maturity in regions of slight precipitation. Several j-ears ago, in Eastern Turkey, a thousand miles west of the part of Persia which we have been considering, I ob.served numerous terraces which I could not then satisfactorily explain. Almost invariably the bottoms of the valleys of Eastern Turkey are filled with gravel in which the streams have incised newer valleys, often to a considerable depth. Thus along the Euphrates River in its upper course, where it flows west- ward before turning southward and eastward on its long course through Mesopotamia, there is a strong gravel terrace almost everywhere except in the narrow canyons. In the Malatia plain, for instance, this terrace ranges from 30 to 60 feet in height. Farther upstream, along the eastern branch, or Murad Su, a few miles east of Pertag, there is a half-consolidated gravel which evidently was deposited in the valley after it had attained nearly its present fonn, and there are also two terraces, one about 50 feet high and the other nearl)' 100. In the small tributary valleys of Pekanik and Kurdemlik, which here descend steeply northward from the Harput Mountains, there is a dissected valley deposit of alluvium which reaches a thickness of 100 feet. The deposit is for the most part composed of silt and very fine gravel, quite different from the cobbles and coarse gravel which now fill the stream-bed. In these deposits and in many others there are marked imconfonnities like those of Bajistan, where relatively coarse material suddenly succeeds fine silt. Still farther up the Euphrates, and along some of its main branches, as for instance, in the Harput and Peri plains, there are extensive gravel deposits in which the streams have deeply intrenched themselves. As the higher mountains of Dersim are approached along the Peri and Muzur rivers the terraces become more distinct. In my notes on a number of the smaller streams there are references to "alluvial terraces," "terraced valleys," "a series of terraces," or "several terraces," most if not all of which are cut in gravel. The number of terraces is not stated, for their possible significance was not then appreciated, and most of them are small features, easy to overlook. Terraces are found in other parts of Turkey in addition to the Euphrates Valley. My notes contain references to similar phenomena along the Tigris in its upper course southeast of Gyuljuk, along the Kizil Imiak or ancient Halys, along the 272 THE BASIN OF EASTERN PERSIA AND SISTAN. tributaries of the Yeshil Irinak or Iris, and along the steep mountain torrent which flows from the lofty Pontic range northward to the Black Sea at Tre1)izond. These phenomena are probably due to the same cause as the similar phenomena farther east in Persia and Turkestan. TERRACES IN NORTH AMERICA. The southwestern part of the United States is not unlike large portions of Central Asia, and among its higher mountains we should naturally look for gravel terraces if our conclusions concerning climatic changes are correct. As a suggestion of the sort of phenomena to be looked for, I shall cite a few examples which I saw in Utah and Arizona during the summer of 1902. The first example is the Kanab Canyon, in Southern Utah, which has been described by Professor Davis {b, pp. lo-ii). This steep-sided young canyon con- tains "two terraces of well-stratified alluvium, usually of fine texture and containing lateral unconfonnities such as are to be expected in the deposits of aggrading streams. The higher terrace is 80 or 100 feet over the stream-bed. It is less continuous than the lower one, which stands from 40 to 75 feet over the stream. The channel below the lower terrace is the work of a series of floods, beginning in the summer of 1883. A great part of the alluvium then accumulated along the valley was swept rapidly away." In external appearance and scale these terraces are like many of those found in Persia and Turkestan, and the character of the surrounding mountains is the same in both parts of the world. The sudden sweeping away of the alluvium from the canyon and the formation of the lower terrace in the course of a few years may be compared with similar action taking place in Asia. At Naumzabad, a few miles south of Serakhs on the Heri Rud (Tejan River), my guide pointed out a place where, during the great flood of the preceding spring, whose appearance at Tejan has iDeeii described b)' Professor Davis, a mass of alluvium half a mile long and nearly a thousand feet wide was washed away, leaving a bluff a hundred feet high. Among the mountains of Persia it frequently happens that if a terraced valley be followed toward its head, points will be found where the terraces, one after another, come to an end. Often this ending, especially in the case of the lowest terrace, is very sudden, and it is manifest that in ever}- great flood the inner channel cuts head- ward and the terraces are prolonged upstream. A less marked, though distinct, example of the same process of valley-filling and terracing is found along Le Verkin Creek, near Toquerville, 50 miles west of Kanab. The bottom of the young valley of the creek is filled with from 10 to 20 feet of alluvial gravel, which the stream has now dissected, fonning a rude terrace. These few examples of terraces in Turkey and North America are not supposed to lead to any definite conclusion, but are presented merely with the purpose of showing that if our conclusions as to the terraces of Central Asia are correct, these features in other lands are what we should expect. Prolonged study is necessary before we can correlate facts so widely separated. The glacial period was a world- wide phenomenon, and to understand it fully we must take a world-wide view. QUATERNARY CLIMATIC CHANGES OF EASTERN PERSIA. 2/3 THE NATURE AND THE METHOD OF ACTION OF THE QUATERNARY CLIMATIC CHANGES OF EASTERN PERSIA. If we admit that the terraces of Eastern Persia are due to climatic changes, we are at once confronted by the question of the nature of the changes and the method of their action. It seems reasonable to suppose that the nature of the changes was the same as that of the changes which took place in glaciated countries at the same time, although differing in degree. Till recently it has generally been a.ssumed that the glacial period was characterized by increased precipitation accompanied by greater cold. Penck and Bruckner have shown, however, that certain phenomena in the Alps can only be explained on the supposition that the precipitation remained nearly constant, while the degree of cold increased and evaporation therefor dimin- ished to such an extent that glaciers and inclosed lakes expanded greatly. Our knowledge of Persia is too slight to justify any conclusion as to whether the climate of the flu\ial and lacustral epochs was characterized chieflj- by greater cold or by greater precipitation. The question can not be wholly neglected in this report, however, for if, as seems probable, the last of the fluvial epochs occurred since the occupation of the countrv- by man, the character of the change must have had an important bearing on human development. A little light may be shed on the question by considering the conditions which must have prevailed during the formation of the terraces. The most important and universal condition for the production of climatic terraces seems to be that during an interfluvial epoch like the present the slopes of the mountains shall be ungraded, and during a fluvial epoch graded. A general view of Western Asia from Chinese Turkestan to Turkey shows that terraces are well developed among young mountains such as the Tian Shan range in Turkestan and the eastern part of the Taurus range in Turkey, where ungraded slopes are the rule. The)- are also numerous among mature mountains, provided the region is so arid that ungraded slopes are charac- teristic of maturity. Such a condition, as we have seen, is well illustrated in Eastern Persia. Among mountains which have reached the stage of maturity, and are not so arid as to remain ungraded, on the contrar\-, terraces are poorl)- developed, as is shown among many of the lower mountains of Turkey and to a less extent of Turkestan. The cause of the prevalence of terraces in regions where the slopes are to-da}- ungraded seems to be that in such regions a change of climate is able to produce marked effects upon the character of the slopes, either by causing more rapid weathering or by causing the slopes to assume a graded condition. .\nother condition of terrace formation is that terraces do not occur to any great extent in regions of deposition such as fans. When found upon fans they almost always soon die out downstream, showing that they owe their origin to impulses derived from farther upstream among the mountains. Accordingly, in considering the process of terrace-making we may confine our attention to the mountains and to those parts of the mountains where erosion is actively at work upon ungraded slopes. It is difficult to estimate the effect which an increased degree of cold with unchanged precipitation would produce upon ungraded slopes ; for among the moun- tains as tlie\' stand to-day the colder, more elevated portions are also subject to 274 THE BASIN OF EASTERN PERSIA AND SISTAN. greater precipitation. And in the same way a comparison of winter and summer conditions affords no assistance, for the colder winters are also times of relatively large precipitation. Nor does it help lis if we compare different years, the colder with the wanner ; for we have no statistics as to the growth of vegetation, the length of rivers, and the other factors which affect the problem. If we suppose, however, that the precipitation remains constant and the degree of cold increases, the amount of evaporation must decrease and the size of ri\'ers and lakes correspondingly increase. It would probably require a great decrease in temperature to bring the lakes to the dimensions of even the more recent lacustral epochs. Another effect of increased cold would be an increase in vegetation and perhaps in the rate of weathering of the rocks by reason of the greater amount of moisture which would remain in the gfround. Here again we have no means of measuring the effect of any possible increase in cold, and so can not feel any assurance as to the adequacy of this cause to produce the observed effects upon the erosion and deposition of streams. The influence of an increase of rainfall upon the ungraded slopes of mountains such as those of Turkestan and Persia can be more easily estimated. In the case of young mountains with slopes so steep that they can not possibly become graded, the whole effect of increased precipitation would be to accelerate weathering and thus to increase the load of the streams. In the case of streams which were approaching grade, but were not yet graded, the result of the increased load would be that it would no longer be possible for the streams to cut downward, because they would be so heavily loaded as to cover their beds with debris. Hence they would cut laterally and form flood-pains covered with gravel. Upon the advent of a drier time the load of the streams would decrease, but their carr}-ing power would remain almost the same ; for the carn,-ing power of a stream depends upon its maximum size, and the maximum of flood size of streams in arid regions is almost as great as in moister regions. With lessened loads and unlessened capacity the streams would begin to cut downward once more, and terraces would be formed which would show a cap- ping of gravel with solid rock beneath, as is common among the lofty and arid young mountains of the southern border of the Tian Shan range on the northern side of the Kashgar basin. Among young mountains, where the main streams are graded, the result of increased rainfall and increased load would probably be that streams would build up their flood-plains and the valley bottoms would become filled with alluvium, most of which would be gravel. A drier epoch would allow this to be dissected and terraces composed wholly of gravel would be fonned, like those found in the moister parts of the Tian Shan Mountains, and to a certain extent in Persia. Thus among young mountains o.scillations between an arid and a moister climate would apparently produce two kinds of terraces ; first, ungraded valleys would contain terraces cut partly in rock and partly in stream-laid gravel ; second, graded valleys would contain terraces cut wholly in stream-laid gravel. In these two cases the terraces of young mountains are the result of a changed climate, that is, the maximum effects of deposition and of erosion are produced under the extreme conditions of moisture or of drought. Among mature but ungraded QUATERNARY CLIMATIC CHANGES OF EASTERN PERSIA. 275 mountains, on the other hand, terraces seem to be the result of a changing climate, that is, the maximum effect, of deposition at least, is produced during the change from moist to drj' conditions. A large number of the terraces of Persia, it will be remembered, are cut in stream-laid gravel which lies with a slight unconformity upon finer deposits of silt. It may be that these can be explained as the product of epochs of increased cold alternating with epochs of relative wannth, but data are as yet insufficient. It is also possible to explain them as the product of epochs of increased precipitation alternating with epochs of relative aridity, but this theory does not necessarily exclude the other. In Persia, as has frequently come to our notice, the rock slopes of mature mountains are ungraded because of the aridity of the climate. If the climate were to become moister the process of grading the slopes and covering them with vegetation would at once begin. So long as solid rock lay near the surface the increased moisture and the increased number of decaying plants would accelerate the process of weathering. Whether this increased weathering would increase the load of the streams depends on whether the increased vegetation is able to hold back the larger amount of waste which is now supplied by the decaying rocks. However this may be, it is certain that the load of the streams would become finer as the process of grading the slopes went on, and ultimately the flood-plains would be covered w'ith fine material, usually silt, no matter whether the streams were aggrading or degrading their beds. When the climate once more becomes arid the graded character of the mountain slopes will soon disappear and the old conditions will reign once more. The process of grading the slopes must of necessity be slow and lag long after the change of climate which gives rise to it, for nmch time is required to convert solid rock into soil. The process of ungrading the slopes, on the contrary', is rapid, and scarcely lags behind the change of climate which causes it As soon as vegetation begins to drj- up because of decreased rainfall, the streams will begin to carry off the soil and weathered fragments which cloak the mountain sides. The carrying power of the streams will remain approximatelj- the same, but their load will be so greatly increased that they will be obliged to deposit the coarser portions upon the silts of the valley flood-plains. This process of building up deposits can not last indefinitely, however, for the supply of weathered material is limited, and when once it is exhausted the weakened forces of weathering can ftimish new supplies ver}- slowh-. Therefore it will continue while the climate is changing. When the change is fin- ished and the climate has become arid, the streams will no longer act as heavily loaded agents of deposition, but will be insufficiently loaded and will act as agents of erosion. Other more striking examples of terraces exist in the semiarid regions of North America, but little attention has been paid to them. It must not be understood that these few examples of terraces in Turkey and North America are supposed to lead to any definite conclusion. They are presented merely with the purpose of showing that if our conclusion as to the climatic origin of the terraces of Central Asia is cor- rect, these features in other lands are what we should expect. Prolonged study is necessary before correlating facts so widely separated. The glacial period was a world-wide phenomenon, and to understand it fully demands a world-wide view. 276 THE BASIN OF EASTERN PERSIA AND SISTAN. SISTAN. The basin of Sistan is unique. Its streams, at least during floods, focus in a fresh-water lake, exceedingly flat-bottomed and shallow, and without an outlet to the sea. About this circles a broad band of reedy swamp, the home of innumerable wild fowl and of the strange Sayids who gain a livelihood by netting them. Next comes a band of smooth, rich plain, splendidly fertile and capable of supporting a dense population, but bounded suddenly and even encroached upon by the grim belt of the surrounding desert. Wastes of blown sand, dry pools of glistening salt, and vast expanses of dark, lifeless gravel fonii the desert which comprises half the area of the basin and completely cuts off the inner, more hospitable regions from the surrounding mountains and the rest of the world. In its sterile wastes all the streams except the Hehnund wither to nothing and are wasted, except when the floods of spring cart)' them clear to the central lake. Outside of these four belts — the lake, the swamp, the plain, and the desert — the basin is everj'where bounded by mountains. On the west and south, where they lie close to the lowest depression, the mountains are low and arid. The streams which rise in them are mere wet-weather torrents, which lose themselves in the piedmont gravel a few miles from their source. To the east, however, and even more to the north, the mountains are among the grandest in the world. From the northeast angle of the basin, near Kabul, the continuation of the Hindu Kush Mountains stretches westward for a distance of 400 miles to the Afghan depression. Of this slightly explored region, larger than New England, we know almost nothing, except that magnificent mountains, from 10,000 to 17,000 feet in height, pour their melted snows into the tremendous gorges of rushing rivers, the Hamd, the Farah, the Khash, and the many branches of the Hehnund. Where these streams reach the lower mountains, their valleys widen and are filled with fields, orchards, and prosperous villages, and a strip of green abundance intervenes between the sterile mountains and the sterile plain. (See plate 6, opposite p. 288.) THE HELMUND RIVER. The main features of all the larger rivers of the Sistan basin may be illustrated by a single example. The Hehnund of the Afghans, the Rtymander of the ancients, is the only large river between the Tigris and the Indus. Rising among great mountain peaks which tower to heights of over 15,000 feet, the Helmund flows through the land of the Hazara Mongols (Holdich, a, p. 42), "a wild mountainous country' of which no European has seen much more than the outside edge. It is a high, bleak, and intensely inhospitable couutr)', where the snow lies for most months of the year, where little or no fuel is to be found, and cultivation is confined to the narrow banks of the Helmund and its tributaries." F'arther downstream, near the edge of the mountains, Zamindawar, northwest of Kandahar " is a beautiful countr}-, stretching up in picturesque valleys and sweeping curves from the Helmund, and filled with a swarming population of well-to-do cultivators" (p. 43). From Zamin- dawar the river flows southward, and not far below Girishk enters the desert, through which it flows for 300 miles to Sistan, first southward, then westward, and lastly northward. On the left lie the deserts of Registan and northern Baluchistan, which McMahon (a, pp. 13, 14, 16; b, p. 290) and Holdich (rt, p. 104-105) describe SISTAN. 277 as consisting of flat plains of fine allnvinni and dark gravel over which the fierce north winds drive fields of sand-dunes. On the southern edges of the desert the dunes often attain a height of 200 feet, and enormous drifts of sand bury- the volcanic mountains of northern Baluchistan to depths of one or two thousand feet, or even more (McMahon, b^ p. 290). North of the Helmund River the Dasht-i-Margo, or Desert of Margo, which was crossed b}- Ferrier (rt, p. 400), appears to be of much the same character, although the sand-hills are not so high apparently, and the area of fine silt exceeds that of gravel. The river itself flows in a distinct valley of erosion, which Colonel McIMahon (described to me as being broadly open, with three or four persistent terraces of gravel, like those which will be described later as occurring along other streams nearer to the Hamun-i-Sistan. Between these receding terraces lies whatHoldich («, p. 106) calls " the curious green ribbon of Helnumd cultivation which divides the great untraversed wastes of the Dasht-i-Margo from the somewhat less formidable sand deserts to the south." " Here in a narrow little space of a mile or so in width we found the great river shut in with a green abundance, infinitely refreshing and delightful." Jungles of tamarisks border the river, and here and there nomad Baluchis feed their flocks, or even cultivate fields of grain. Far more impressive than the modern villages, however, are the innumerable evidences of a far greater population which finally disappeared not many hundred years ago. Everj' writer on the region dwells on the " cities of the dead, spreading out like gigantic cemeteries for miles on either side of the river, gaunt relics of palaces and mosques and houses, upright and bleached, scattered over acres of debris, masses of broken potter}-, mounds of ancient mud ruins. . . . The extent of these Kaiani ruins (dating their final destruction from a centur}^ and a half ago) would be incomprehensible were it not for the extent of the indications of that canal system which was developed from the Helmund to assist in supporting the crowd of humanity which must have dwelt in the Hehnund Valley " (Holdich, «, p. 107). The other main afiluents of the Haniun-i-Sistan repeat the features of the Helmund on a smaller scale. Rising in the mountains south of the Heri Rud, they run southwestward to the desert. Through this they flow in intrenched valleys which are probably like that of the Helmund. Along their courses through the plains, ruins replace the settled villages of the upper valleys, while at the heads of the deltas not far from the lake of Sistan the remains of ancient cities, such as Peshawaran, cover the plain for miles. Except for the distributaries which travcr.se the western half of the delta of the Helmund, all the important streams of the Sistan basin are located in Afghan territory-, where exploration has always been exceedingly difficidt. To-day it is practically impossible for a European to enter the country-, and we must perforce rest content with the scanty accounts contained in the works of a handful of adventurous explorers half a centun,- ago. DESCRIPTION OF SIST.\N. The district of Sistan occupies a shallow depression on the southwestern edge of the Sistan basin. It comprises the lake, the swampy belt of reeds, and the low arable plain. Along the western border for a distance of 50 miles or more the 278 THE BASIN OF EASTERN PERSIA AND SISTAN. plain and the swamp are absent, and the lake at high water meets the gravel desert. In approaching Sistan on this side by the ordinary ronte from the northwest, the traveler mnst pass throngh the Gate of Rendan, a gorge cut across a low ridge of limestone. The bottom of the gorge is filled with fine alluvium, chieflj- silt, which is rapidly being cut away by the stream (cf. the Kanab canyon in Utah, ante p. 272). The latter luis intrenched itself to a depth of 20 feet. This gate is remarkable for its large grove of date palms, which flourish here in the shelter of the mountains, although alsewhere in Sistan the violent wind prevents their growth. Soutluvest of Bendan the alluvium of the gorge broadens into the gravel-covered desert of Sistan. As far as the eye can reach it encounters a smooth expanse of small dark pebbles, clean swept by the wind, and devoid of vegetation except for a small bunchy weed every two or three hundred feet (fig. 164). Valleys are incised in this plain, but are so sharply depressed as not to break the lifeless monotony of the ^Tavel, which is only interrupted by islands of buried mountains. The valleys are Fig. 164. — A Typical Portion of ihe Gravel Desert northeast o( Sistan. universally terraced. Along the Bendan stream a second terrace soon develops below that at the gate. These two continue to the mouth of the valley, varying in height, but very persistent. In many places a third small terrace appears below these, but it is not persistent. All along the west shore of the lake the same thing seems to be true ; the main streams are bordered b}' two good terraces and there are traces of a third. In the side valleys the two lower terraces soon disappear. East of Bendan the gra\'el desert suddenly comes to an end in the steep bluffs which border the lake on the northwest. At Bereng, where the road to Sistan crosses the " hamun " (swamp) the bluffs are only 20 or 30 feet high, and stand somewhat back from the water. Farther north, however, they approach the water until they are undercut by it and fonn almost perpendicular cliffs 100 feet high. Still farther north, near Kharikha and Kuh-i-Chaku, the total height of the bluflfe becomes 300 or 400 feet, although the)- stand farther from the lake and are not to-day being undercut. Just how far these bluffs e.xtend is not known. I followed them for 40 miles from Bereng to the northwest corner of the lake, and saw them SISTAN. 279 stretching eastward along the northern shore for at least another 25 miles. On the opposite side of the lake, sonth of the delta of the Helnuind, I followed them again for 30 miles, and saw them extending indefinitely farther in both directions. On this eastern side of the lake they lie far from the present shore, and ninst have been cut when the lake stood higher than now. So far as I can gather from the chance remarks of travelers who have approached Sistan from \-arioiis directions, the whole of Sistan, including the lake, the swamp, and the arable plain, is surrounded by these wave-cut bluffs (Bellew, p. 263, 264). Sometimes the bluffs stand close to the lake and attain a height of hundreds of feet, while sometimes, especially on the east side, they are distant 20 or 30 miles from the shore and attain a height of only about 25 feet. Everj'where the cliffs are composed of alternating pink silt and white or greenish clays, capped with gravel. Fig. 165. — A Raft o( Reeds poled by a Sayid, or " Fowler," on the Edge of the Swamp of Sistan. The district surrounded by these lake bluffs is the real Sistan. It has a breadth of about 60 miles from east to west and a length of 100 from north to south. Wlicn the traveler, arriving by the main road from tlie northwest, first views Sistan from the bluffs back of Bereng, he is impressed 1)\- the monotonous uniformity and flatness. In front, if the lake level be high, lies a broad sheet of water, blue sometimes, but oftener a dull gray to match the hazy sk}'. Here and there, (figs. 165 and 166) surrounded by the water, or fringing it, stretch miles upon miles of "naizar" or reedy swamp, green in summer, l)ut in winter sadly brown or blackened by fire, where the inhabitants of the swamp have burned the reeds in order to facilitate the growth of the young shoots on which the cattle grow fat. Bordering the reed-beds, and blending imperceptibly into them, come the fertile fields, green, flat, and treeless, except where the rivers flood the land in spring and allow the growth of graceful tamarisk jungles. In all the view there is nothing to 28o THE BASIN OF EASTERN PERSIA AND SISTAN. break the unmitigated flatness except the dark tabular mass of the volcanic mesa of Kuh-i-Klioja, rising as a black island from among the brown reeds and gray water. The lake of Sistan has been a cause of wonder to most of the writers on the region because of the fluctuations of its level. Their wonder is perhaps natural, although the changes differ only in degree, not in kind, from those to which every inclosed lake is subject. A single example will illustrate the matter. Early in the year 1903, when the British Arbitration Commission arrived at Sistan, there was no lake at all, and the very lowest hollow in the northwest corner was dr}'. At the very time when the commission arrived, however, the spring floods from Hindu Kush were beginning to come down in great force. The lake was rapidly filled, and within a few weeks had assumed the extreme dimensions shown on the map. It was at this time larger than at any period for many years. Such sudden and Fig. 166. — An Arm of ihe Lake ot Sistan. In the (oreground are beds of reeds ; in the background, ihe lacustrine plain. widespread changes in the distribution of land and water have taken place again and again in the past. They are naturally impressive, even though the}- are nothing but the normal beha\ior of an inclosed desert lake fed by streams from lofty moun- tains. The hollow of Sistan has been so largel>- filled with silt that the bottom of the lake is exceedingly flat. Even at high water the Sayids pole their reed rafts almost everj'where. The people say that in the deepest places the water is " as deep as a man with upstretched arms." Where I examined the lake bottom it con- sisted of fine greenish or white clay which clung tenaciously to the poles of the raftsmen. Near the edges of the lake and on the plains round about, the material is the same clay mixed with more or less sand. At present fine sand seems to be the coarsest material brought down by the streams, and all of this is deposited immediately in the deltas. The main body of the lake is free from visible sediment and the water is clear and drinkable. SISTAN. 281 The drinkable quality of the water of Sistan is another of the qualities which many writers have deemed remarkable. At times of \'ery high water, perhaps once in a dozen years, the lake possesses an outlet to the south which will presently be described. The amount of water passing through this, however, is a most minute fraction of the tottd which reaches the lake, and as it passes out at the time of high water, when the percentage of salt dissolved in the water is least, the amount of salt carried by it must be ver\' small compared with the total amount brought in by all the tributaries. The amount thus brought to Sistan in a single year, or in a score of years, ma}- be insignificant, but it must be large compared with that carried by streams in moist countries. Ferrier (pp. 400 ff.) describes the Dasht-i-Margo, through which the Helmund flows, as full of salt pools. Bellew (pp. 166, 168, 172, et al.) found the soil of the Helmund Valley highly charged with saline matter. In one place close to the river, a region some 10 miles long contained several thousand pits from which the people extract salt for commercial purposes. On the opposite side of Sistan, to the northwest, many of the tributarj' streams are strongly impreg- nated with salt. The Shor Rud (Salt River) of Durukh proved so saline that we could not drink it. The Gisha stream was drinkable in December, although our guide said that in summer, when the brook is reduced to a few pools, not even camels can drink the water. In the same way the Bendan stream and the other seeping brooklets which I saw along the northwest shore of the lake are all bordered by incrustations of .salt ; and lastly, the unconsolidated strata of the bluffs and of the lacustrine plain on all sides of Sistan are frequently white with saline matter. Clearly the water of the lake is not fresh by reason of any lack of salt in the sur- rounding basin. The amount of saline matter brought in each year b}- the streams must be large. It is possible that the freshness of the lake is due to its occasional overflow. If we suppose that a flood occurs ever}' tenth year and carries out of the lake a tenth of the water which is that year discharged into it, the nia.ximum salinity of the water would be one hundred times that of tlie tributary rivers. Under such conditions the water might be apparenth' fresh, although as to this we have no data. It is probable that the amount of water escaping from the lake is less than a tenth ever}' tenth year, and the salinit}- should be two or three times as great as we have esti- mated. Another explanation of the lack of salt is that in comparatively recent times the lake stood so much higher than now that it overflowed permanently, and was flushed clean. Other lines of evidence, as we shall see, point to this conclusion. It is mentioned here to show that while the freshness of the lake proves nothing, it is strictly in accordance with the theory which will be considered later. THE DELTA OF THE HELMUND. The most important part of Sistan from a human standpoint is the arable plains which lie outside the central expanses of the lake and swamp. In certain places these represent a shore platform cut by the waves when the lake stood higher. Elsewhere they represent a portion of the general lake bottom, now laid bare by the 282 THE BASIN OF EASTERN PERSIA AND SISTAN. retreat of the waters. The most important plains, however, are the deltas of the larger streams on the northern and eastern sides of the "haniiin." Most of these lie in Afghanistan and are almost unknown, but the largest, that of the Helmund, is partly in Persia and has been frequently described. To the eye the delta seems to be a flat plain, merging into the reed-beds on the one hand and ending abruptly at the foot of the bluffs on the other. Toward the lake the soil is clayey like the lake bottom, and is exceedingly slippery and stick)- in wet weather. Toward the head of the delta it gradually changes to very fine sand, in which there is a considerable proportion of clay. Everj-where the soil is fertile if properly irrigated. Where cultivation is carried on, the whole countr}- is often half under water. Deep and Fig. 167. — Canals in the Delta of the Helmund at Sistan. One canal crosses the other upon a bridge of weeds. rarel)- bridged canals wander here and there, and even cross one another on bridges, which are nothing but dried weeds packed into the water and covered with clayey soil (fig. 167). Grain and melons grow luxuriantly, but other crops are rare and fruit can not be raised because of the wind. At present large tracts are not under cultivation and are covered with a spiny growth of camel thorn bearing purple-pink flowers, or with a dense growth of tall tamarisks forming an almost impenetrable jungle 20 feet high, the home of innumerable wild boars and jackals. In still other places, as at Zahidan, the delta is being invaded and buried by sand. At first sight there appears to be no special reason win- certain areas should be cultivated, others should be left to camel thorn, still others should be covered with tamarisks, while the most unfortunate parts are being destroyed by sand. The explanation is SISTAN. 283 easily found, however. The delta of the Helmund, like every other delta, not only slopes from apex to front, but consists of a number of broad, almost imperceptible ridges separated by hollows equally broad. The ridges indicate tlie location of the main stream in former times when it built up the inner edge of its flood-plain and left slight depressions on either side. To-day the ridges are largely abandoned to the encroaching sand, although in the not far distant past they were the most populous parts of the country. Their slight elevation of 5 or 10 feet adds to the difficulty of bringing water to them, although this is of relatively slight importance. The main reason for abandoning them seems to be that they He above the level where perennial underground water can be reached by the roots of the crops. Therefore a greater amount of water is required for irrigation, and a drought does nuicli more damage than in the regions a few feet lower. In proof of this it is only necessar}' to examine the distribution of vegetation. The ridges and the upper parts are for the most part, though by no means uni\ersally, abandoned to the prickly camel thorn where they are not being o\er\vhelraed by sand. The troughs, on the other hand, are occupied by the tamarisk jungle wherever they are liable to inundation, and are tliickh' studded with villages. The larger part of the cultivated land, however, lies in the low, flat regions along the borders of the delta, where the level of permanent underground water is but a few feet below the surface and can be easily reached by the crops. Lovett, {b, p. 146) cites a good example of the rapidity with which changes in cultivation take place in response to changes in the water level, although he himself ascribes the change to an improvement in the government and a temporary' sense of greater security. Arriving in Sistan in 1872, at the end of a six years' drought, during which the lake had practically disappeared, he found that the countrj- around Kuh-i-Khoja was dr^- and was covered in part with tamarisks and in part with fields, although Connolly in 1842 described it as under water. "Now, however," says Lovett, "cultivation has advanced to within two miles or so of the island (Kuh-i-Khoja) ; in fact, has been developed pari passu with the retreat of the waters which has been assigned as the cause." To-day the villagers endeavor to plant their fields as close to the lake as possible. In February' I saw men ploughing in deep mud on the very edge of the water, and rode across old fields which went under the lake and had e\identh- been CTilti\'ated a few years before during some drier season. At present, ruins, camel thorn, and sand occupy the higher portions of the delta, while villages, fields, and tamarisks occupy the lower portions. Strangely enough, the latter contain no ruins of any considerable age, although if conditions in the past were the same as to-day these must have been the most desirable parts of the country. The only adequate explanation of this phenom- enon seems to be that the lake stood at a higher level during a past not far remote. THE SHILA AND THE GOD-I-ZIRRAH. In times of heavy flood the lake of Sistan overflows and sends a stream of water down the Shila 40 miles to the south and then 50 to the .southeast, to the God-i- Zirrah. The Shila, where Sykes ( feel— A 1 1 c r n ■ t e gravel and lUt (3) 7 14) 5 (5) 17 — GrecB day - Pink cby — Crten clay ^Yellow (and — Brovan landy clay imwA —Green clay — Yeilow clay — Purple clay -Pink dav -Green cUy -Pink iSi Mod sy^ig?^:^ Gravel " -Pink clay . — Fine srey taod [[ -Pink day — Pinkcuid —Pink clay, witb « Kttlc lime- ■tone ffypMUD near baic — Fine tand (di»- conlinuom) .. -Pink day ^^ —Fine brown (and ,, — Cypnun — Pmk day. wilh la yen of land and itrcan> ^^ channel) "— Cfceo day Banded gteen clay —Fine land and BTeen day 4 " -Pink clay il) 12 feei-Cr.vel '2) 4 •• -Pinkcb, (3) 4 ' 1 ^4 (5) 2 U) 10 U) 13 — Green clay -While (Uy — YeDow clay -Pink cUy (9) J4 • ( 10) 3^i - Green clay -Pink clay, with jishtfT tandy bandi -YrDow .lay — Hard pint clay, undy ftCTWH 1*4 (« » ■■ - ^^ (7) 10" -P^^t ?^!! ^^ a) i»" - -F-acUi (HI i--OM^ an J' -p-t*""" ■^ I!) 20 " -Pal A (i) t " -D«» Bin ^^^ gg^^; CI) i " -Canluduad S •■ -Pu.k A 4 " -Cmntlir (ID) 30 " -P«l d>, I (27) 3 ^S^' i^a ^^ Z^ Ml IJ ■■ -(PbI.* IJJ » " - Cn»I 111) 3 ■ 'Ml r- .1,. u,^ ( Bindiru -FulcUf i» 27 ■■ -Ptafc a [«) 35 " -'^'"^£3* !^-;'V -F« n-"l 2*1 )S " -Pull tUT. p< IIS) 2---Ffl.rcU><'wd IJfl) 4" -Fiw tm-n 291 «■■ -Cirw^," I)}) ] " -Puk Uiy ud>e>< (3*) * ■■ -OmdcI-. OS) 10" -PoltW (361 I ' -Faiud 1)7) 12" -Pmld., 136) — " — Bud ol (h uhI 139) S ■■ -<>« l<. [II e I, 12) B « -CMdu L 141 I " -Y.l»(lw (»)24 "-Pkidw (A) 10 " -d™ dw (7) I :: z?^;^''^; Ill) 6 '- -Cnaib)! 112} 8 " -PUiUf BECTtON I 13) 14 1*1 54 -W»-.aId» IS) 13 -Ci.nl ■6) 3 -S.HJwJn.«l 1!) 12 ■ -Pi^d„A (IS) e 121) 3S ■-o~. d.,, ^'(101 2 •■ -Ydt-d.. -ini ) -- -Cna.t, SECTION K. ^^ ^^ ^Pl 121 e ~-Puia>T 131 10 " -Fw Md I (4) f, "-Pkldtr 131 10 "-Far lud tad (6) 12 "-Pa-lil., 17) 16 "-CiMdi (I) 4ttlOI>«-CBRl (S) 10 --Ptatd'r II of Lake Drpoiiti Etam Varioui Localion* along ihc Notlhweslcrn Shore ol ihc Lake ol SuUn. o THE QUATERNARY ERA IN SISTAN. 285 carried water to the town of Haiizdar. Even now extreme floods of the Helmund rise high enough to trickle into it on rare occasions. All along the Shila and at the head of the God-i-Zirrah are abundant ruins, all of which seem to date from Mohammedan times. It is evident that the lakes of Sistan and Zirrah and the rivers of Helmund and Shila have undergone a series of changes intimately associated with the human historj' of the region. These changes seem to be explicable only on the theory' that the climate of Eastern Persia has been growing gradually drier during historical times. Before considering this question further we will examine certain phenomena which seem to indicate extensive climatic changes in earlier times. Having examined these, we shall be in a position to judge whether there is an adequate basis for the working hypothesis that the last pulsations of the series of climatic changes known as the glacial period are still in progress. THE QUATERNARY ERA IN SISTAN. THE DEPOSITS OF THE LAKE OF SISTAN. In the preceding pages the conclusion has been reached that while the more northern countries of the world were passing through a glacial period, Persia was passing through a fluvial period due to the same causes and characterized by a similar series of climatic oscillations. The record of the dry and wet or wann and cold epochs composing this fluvial period seems to be preserved in a series of terraces, lacustrine and fluviatile, which occur in all parts of the country. These terraces are unsatisfactory, because the record which they preser\'e is incomplete, and a single, strong, terrace-making impulse may destroy the record of all that have gone before. The best possible record would be one preserv^ed in the bottom of a basin which contained a lake during pluvial epochs, but was drj' or contained merely a playa during interpluvial epochs. Such basins abound in Persia, but the bottoms of most of them are not exposed for study. In Sistan, however, several volcanoes broke out during the latter part of the fluvial period, and parts of the lake bottom were warped upward to a maximum height of over 600 feet abo\'e the present lake level. These have since been undercut by the waves and fonn the bluffs which surround the lake. A proper interpretation of the sections exposed will disclose the history- of the lake far back toward the beginning of the Quaternary era. From a scenic point of view the most notable feature in Sistan is the lava- capped mesa of Kuh-i-Klioja (Mountain of the Teacher). P'rom whatever direction one approaches Sistan he sees a flat-topped hill, low and black, and nearly a mile in diameter. From the encircling reeds and water, steep slopes of dark talus mantling red clay rise 200 feet to the base of cliflTs of basaltic lava, over 200 feet high. The uneven upper surface of the lava is covered with many-chambered tombs, or is roughened with great pits, dug as reserv^oirs perhaps, or for some other unknown purpose. On the edges the lava is being undennincd by the retreat of soft underly- ing clays, and huge blocks are continually falling off, thus preser\-ing the steepness of the cliffs and hiding the strata below. Enough of the latter are seen to show that they are for the most ])art red, with some bands of green, and belong to the lacustrine series so well exposed elsewhere. At its contact with the lava the clay 286 THE KASIN OF EASTERN PERSIA AND SISTAN. is broken into a breccia, and is baked, so that the upper portions resemble a mass of finely broken bricks cemented with brick dust. Kuh-i-Khoja is the remnant of a volcano (see fig. i68) which broke out under the lake, and in its efforts to find exit elevated the sediments of the lake bottom into a dome, which it covered with lava. Around the island thus formed the waves at once set to work, and have now under- mined and carried away all the dome except the central mass. Soon all the clays will be removed and merely a volcanic neck will remain. Similar volcanic outbursts are described by \'redenburg as having taken place in other parts of Sistan and throughout Baluchistan. Smith (a, p. 315) describes "a flat-topped, irregularly-shaped hill, called Kuh-i-Kuchah, somewhat smaller than but resembling the Kuh-i-Khoja." It lies between the Farah and Harud rivers, 8 miles west-northwest of the ruins of Peshawaran. (See jjlate 6, opposite p. 288.) This hill and others like it will doubtless repay close study when it shall be possil)le to travel freely in Afghanistan. Meanwhile there is one mountain, the Kuh-i-Chaku, on the northwestern shore of the Hamun-i-Sistan, which can be studied. It lies in the desert close to the Afghan border and is difficult of access, but it presents such wonderful sections that ^^iniiiiiii^»iiiii|^jljjjjl __^^^^^^ Lake level Fig. 168. — Ideal cross-section of the Mesa of Kuh-i-Khoja. Heavily shaded portions = lava; lightly shaded portions = pink sill ; unshaded portions ^ green clay. it deserves months of study rather than the short week which I was able to give to it and to the surrounding countr)'. The mountain of Kuh-i-Chaku is a mesa like Kuh-i-Khoja, although nuich larger. The clays reach a thickness of 650 feet, and the lava cap 400. The broad top of the mesa presents a relief of from 100 to 200 feet, and two breached craters inclosing hills of scoria can be made out. The upper layers of clay are baked, as at Kuh-i-Khoja, and most of the lower slopes are covered with talus, so that good sections are difficult to obtain directly on the side of the mountain. At the time of the volcanic eruptions which produced the mountain, however, the whole region was uplifted. South of Kuh-i-Chaku a slightly rolling monocline of uplifted clays descends gently for 30 or 40 miles to Bereng, and has been dissected by the waves to form the bluffs which have been described. Fine sections are exposed between Kuh-i-Chaku and Kharikha, where the bluffs reach a height of over 400 feet. LAKE DEPOSITS VERSUS PLAVA DEPOSITS. The accompanying diagram (plate 5) illustrates sections of lake deposits from various locations along the northwestern shore of the lake in the region of the Kuh-i- Chaku uplift, and from the southeastern bluffs along the edge of the Helmund delta in the district affected by the Kuh-i-Khoja uplift. The sections are arranged according to location. The position of each is marked on the map of Sistan by the appropriate letter, A being in the northwest comer, close to Kuh-i-Chaku. With the possible THE QUATERNARY ERA IN SISTAN. 287 exception of two on the Hehnund River, each section contains three distinct parts. At the top, lying imconforniably on the other strata, are beds of orravel from one to a hundred or more feet thick. Below these are numerous alternations between thick pinkish strata and thinner strata of a greenish or whitish color. The pink beds consist largely of clays and ver}- fine silts, but often pass into layers of fine brown sand. Viewed as a whole, the pink laj'ers are \ery continuous, and preserve the same character for mile after mile. In detail, however, they vary considerably, even in short distances. For instance, a layer of clay is often inter- rupted by a band of fine sand which continues a few hundred feet and then dies out. More rarely a la\-er of grit or gravel occurs and, rarest of all, a distinct fossil stream-bed of gravel is exposed. Again, in certain places slight unconformities are discernible, as though a brief period of erosion had taken place between the deposi- tion of one layer and the next. Among the more sand)- lajers there are further evidences of exposure to the air. In one place, for instance, the sand shows ripple- marks, worm-casts, and rain-drop prints. Lastly, the layers of this formation are ever^'where of a reddish tint, varying from pink to brown. The only exception is found in some of the sandier, more quartzose layers, which are gray for a few inches. Everywhere the materials seem to have been exposed to oxidization for a considerable period. They bear the marks of having been deposited subaerially by widely spreading floods or in temporary playas. The white or, more exactly, the greenish clays, on the other hand, present a ver>' different appearance. On the edges they are mixed with fine sand or are more or less banded. Occasional!)' a purple layer occurs, or a band of yellow clay, in which are what appear to be fossil leaves and reeds. The main mass of each stratum, however, consists of solid, unbroken layers of pure clay, unifonn in texture and color, and showing none of the slight variations which characterize the pink beds. The color indicates that the materials were brought rapidly from their place of origin in the mountains and were not long exposed to o.xidization on the way. The green strata as a whole show no sign of subaerial origin, and appear to be t)pically lacustrine. The pink beds and the green beds differ from one another chiefly in manner of deposition. The material of the clayey portions of the pink is identical witli the green, except that it is more weathered, and it is reasonably certain that they were deri\ed from the same source. The discontinuous, highly- weathered pink layers, however, appear to have been deposited subaerially after long exposure to the atmos- phere, while the unifonn, slightl)--weathered green layers appear to have been deposited subaqueously after a relatively short exposure to the atmosphere. Such alternations of subaerial and subaqueous conditions indicate that the lake of Sistan has been subjected to changes whereb)- a portion of its bed has been altematel)- exposed as dr)' land and submerged under water. The duration of each epoch of submergence or exposure must hav-e been considerable, for the accumulation of from 5 to 20 feet of the finest clay, or of a greater thickness of a clayey silt and sand, is a slow process mea.sured in our small unit of years. This is especially true if in former times deposition was as slow as at present. Mr. Tate told me that during 288 THE BASIN OF EASTERN PERSIA AND SISTAN. the year of his stay in Sistan the lake was always clear and deposition proceeded verj' slowly. Even during the great flood of 1903 the water was muddy only off the river mouths, although everywhere covered with the wreckage of reeds and tamarisks. The transition from sul^niergence to exposure must also have been comparati\ely slow, for the change from pink to green deposits is frequently gradual, although always distinct. The .sandy layers mixed with the upper and lower portions of the lacustrine clay seem to indicate shore conditions, and the layers of purple and yellow clay, with the included fossil plants, probably point to the existence of marshes during the disappearance of the lakes. In brief, an examination of the sections exposed in the bluffs of Sistan suggests that in \-ery recent geological times the basin of Sistan has been subjected to a long series of slow and gradual changes by which large portions of the floor of the basin became alternately areas of sub- aerial and of lacustrine deposition. In other words, the predecessor of the present lake of Sistan has either again and again passed from conditions of extreme expan- sion to those of great diminution or else has repeatedly and systematically shifted its position. THE CAUSE OF THE ALTERNATIONS OF THE SISTAN STRATA. When we attempt to explain these variations in the lake, four plausible theories present themselves, (a) The lake may have had an outlet which was repeatedly dammed by volcanic eruptions or otherwise, and as frequenth' swept clear. {/>) Some large tributary may have been diverted alternately to and from the lake, first filling it and then leaving it diminished, (c) The basin of Sistan niaj- ha\e been sub- jected to rhythmic earth-movements by which the lake was poured alternately from one side to the other, (d) The fluvial period may have consisted of a greater number of epochs than has been supposed, and each epoch may have caused an expansion of the lake. (a) Outlet Theory. — If the lake had an outlet as recently as the time of deposition of the clays, traces of it must still remain. The Shila can not be considered in this connection, because the Hamun-i-vSistan and the God-i-Zirrah are on nearly the same level and form parts of a single lake so far as the present problem is concerned. The entire border of the basin of Sistan has not been explored, but it is certain that even the lower passes stand at least 1,500 or 2,000 feet above the lake of Sistan. Any outlet which may have existed in fonner geological times must have ceased to do duty ages before the formation of the modern clays which now concern us. {b) Diversion Theory. — In the case of the lakes of Sistan and Zirrah we have seen that the diversion of the Helmund caused great changes in the area subject to inundation. If a similar change could have taken place repeatedh- in earlier times it might have caused the deposition of alternating lacustrine and subaerial strata. The diversion, if such there was, must have taken place much nearer the mountains. This theory can not be absolutely excluded, because our knowledge of tlie ri\ers in Afghanistan is exceedingly limited. The extreme improbability that a river .should be diverted back and forth eight or ten times at regular inter\als is a strong a priori argument against it. Moreover, if such diversions did take place, it is still necessary to explain win-. Such behavior on the part of a ri\-er could only be due to some systematic cause, such as repeated warping of the crust or climatic changes. PLATE 6. MAP OF SI STAN To the •S/ula, I ■:'-"" ^ //tZUZ<£t2/' KalaiFatK MAP OF SISTAN. THE QUATERNARY ERA IN SISTAN. 289 (c) Rhythmic Warping Theory. — The third possible explanation of the strati- graphic series at Sistan is awarping of the crust, whereby the lake was again and again poured from one side of the basin to the other or, what amounts to the same thing, the streams were deflected and a lake accumulated first on one side and then on the other. This theory possesses one inherent though not insunnountable difficulty. It demands a fonn of warping of which we have no proved examples elsewhere, and which is radically different from that which has taken place in neighboring basins and in the world at large. The progress of geolog}- has led to two conclusions which are not in harmony with the theory of warping as applied to Sistan. In the first place, earth-movements are characterized b}- irregularity rather than regularit}-. They occur spasmodically, now a great movement, now a minor one ; now a short interv^al of rest, now a long interval. The phenomena of Sistan demand an opposite char- acter, approximately equal movements occurring at approximately equal intervals. In the second place, earth-movements are cumulative ; that is, the main changes of a given period consist of repeated impulses in the same direction. For instance, if the world as a whole be taken as an example, the old idea that the oceans have become continents and the continents oceans is abandoned. Almost eversone now believes that the continents and oceans were differentiated far back in early eras, and that in spite of temporary' depressions the continents have steadily increased in height and area and the seas have grown deeper. The same holds true in smaller areas. For example, in the faulted basin region of the western United vStates, it has been shown by Gilbert, Russell, Davis, and others that there has been continued move- ment along the same fault lines, and during a given epoch that movement has been unifonnly in one direction. If there have been reversals, they have only occurred after a long lapse of time, during which the internal forces suffered an entire read- justment. Or lastly, to take an example close to Sistan, the basins of Eastern Persia, as has been shown above, ha\-e gradually grown smaller through Tertiarj- and perha])s Quateniarj' times, by the progressive warping and elevation of the strata along their edges. In not a single instance has evidence been found to show that a basin has alternately grown smaller and then larger. To put it briefly, the move- ments have been cumulati\e, not undulatory. If the red and green clays of Sistan, however, are to be explained by movements of the crust, those movements nuist have been preeminently undulatory — rhythmic pulsations as regular almost as the beating of the heart ; and the final result of a long series must have been to leave the countr}- in the same condition as at the beginning. These objections do not prove that the theory of warping is untenable. They merely show that a warping of a peculiar sort is demanded different from anything of which we have knowledge elsewhere. Granting, then, the possibility of rhythmic cmstal movements by which the lake and rivers of Sistan may have been deflected first to this side of their basin and then to that, do the red and green clays show all the expectable features ? In all but one respect they do. The amount of warping demanded by the tlieory is so slight and may have taken ])lace .so slowly that the streams encroaching upon the abandoned lake bed would spread into broad sheets and would lay down subaerial 290 THE BASIN OF EASTERN PERSIA AND SISTAN. or fluviatile deposits which would merge imperceptibly into those of the lake. Rapid movements would involve unconfonnities between the lacustrine and fluviatile deposits, but slow movements would involve just such transitions as actually exist. The structure and texture of the clays agree with the demands of the theory of warping. The weakness of this theor>' is that it does not explain the difference between the red color of the fluviatile strata and the green of the lacustrine layers. The transition from red to green must mean that the grains of waste at the bottom of a red layer were exposed to different conditions of weathering from those of the green grains a few inches lower. An important and widespread change must have taken place in a short time. It is quite impossible that such a change should take place merely because the border of the lake has been shifted a few miles. Whether the lake shore is a mile or two this side or that of a given point, the deposits must have come from approximately the same mountains and must have been subjected to the .same journey under precisely the .same conditions, except for the last mile or two. If the pink grains have had time to become highly oxidized, it is inconceivable that the green grains, brought by the same stream, have scarceh' had time to become weathered at all. This might indeed happen in the case of two individual grains, one of which was brought from the mountains in a single year by a flood, while the other spent many years upon the way, but it could not possibly happen with an infinite number of grains. The color of the clays seems to be an insunnountable obstacle to the acceptance of the theory' of rhjthmic war])ing. (d) Fluvial or Laciistral Theory. — The theory which explains the phenomena of Sistan by a succession of fluvial and interfluvial ejx)chs is an expansion of the principles which have become so well established in the study of the glacial phenom- ena of Europe and North America. During fluvial or lacustral epochs the increased rainfall or decreased evaporation would cause a large lake in the basin of Sistan ; the streams from the surrounding mountains would become fuller and more perennial, vegetation would become more abundant, and the mountain slopes would tend to become graded. As a result of all this the load of the stream would be fine in texture and would be carried quickly to the lake, where it would be deposited without having an opportunit)' to become highl}- weathered. The lake bottom would be covered with unoxidized clays of fine texture and light color. On the advent of an interfluvial epoch, the lake would decrease in size, and marshes would encroach upon its edges ; the rivers would dwindle and become intermittent, and at the same time would become subject to fiercer floods ; vegetation would ever}-where decrease ; and the slopes would become ungraded. These changes would allow coarser materials, such as sand and even gravel, to be washed in over the exposed portions of the old lake bed. The total amount of material might be greater than during the moister period, for the flood torrents would be loaded to the utmost ; but the jotiniey of a given particle would be much slower, for the laden floods would quickly spread into a sheet and deposit their loads, and many short journeys separated by long periods of exposure woidd be required to bring the waste of the mountains to its final resting place. During this protracted journey the redness which characterizes the fluviatile THE GRAVELS OF SISTAN. 29I strata would be acquired through oxidization. A succession of ten fluvial and inter- fluvial epochs would account for all the observed facts of the clays of Sistan. There is therefore reasonable ground for the working hypothesis that Sistan, and pre- sumably the Iran basin, has passed through at least ten fluvial epochs during the Quaternary era. The number of these epochs is surprising and adds interest to the question of their relation to the glacial epochs of other countries. THE GRAVELS OF SISTAN. Before we can consider the question of the relation of the fluvial period of Persia and the glacial period of other lands, it will be necessary- to ascertain the history- of Sistan since the volcanic outbreaks which elevated the clays. The first part of this history is recorded in gravel deposits, and the later part in terraces. A reference to the diagrams of the sections (plate 5) exposed in the lake bluffs shows that at the top of each a stratum of gravel lies uncomformably on the cla)s. In sections C to F the gravel is greatly developed and reaches a thickness of from 100 to 150 feet. These sections are located a few miles south of Kuh-i-Chaku, in a region which received the full force of the uplift due to the volcano, but was not covered with la\-a like A. Their situation is most advantageous for the preservation of a record of all the non-volcanic events since the eruption of Kuh-i-Chaku. The eruption took place during a time of gravel deposition, as appears from the gravel under the la\-a in section A and the much greater thickness of gravel which accumulated nearby outside the lava-covered area. The change from the deposition of silt to that of gravel was probably due to an uplift of the borders of the basin, whereby the slope of the streams was steepened and opportunity gi\-en them to carry away the material which had accumulated upon the graded slopes of the mountains a few miles to the west, or in the small basins scattered among them. Evidence of such an uplift is found in the stage of dissection of the mountain range on the western border of Sistan, and in certain lava sheets. West of Bendan, on the road to Neh, a large sheet of dark lava, from one to three hundred feet thick, fonns a high mesa, like Kuh-i-Khoja and Kuh-i-Chaku. The lava does not rest upon clays, however, but upon a broad, smooth expanse of relatively soft limestone and shale, both of which are evenly tnmcated by a surface of erosion. This surface could only have been reduced to such smoothness by long erosion at a lower level, for the strata vary much in hardness and are highly folded. Most of the mountains round abotit are young in appearance, although few of them stand higher than the mesa. The peaks are shai^p and well defined, even though some of them con- sist of the softer strata. The slopes are naked and steep, and the valleys, which to a large extent follow subsequent courses along the softer strata, are narrow, with ungraded sides. Rising above the mesa and the lower peaks are a number of large, flat-topped mountains, most, if not all, of which are composed of more resistant limestone. Apparently at the time of the eruption which fonned the lava-sheet capping the mesa, the country- stood lower than now and consisted of hills of gentle relief, from among which rose residual mountains of limestone. Such a mature country is exactly what might be expected at the end of the long, quiet period during which the alternating pink and green clays of Sistan were deposited. 292 THE BASIN OF EASTERN PERSIA AND SISTAN. While there is no direct evidence as to the time of the uplift, it seems safe to associate its inception with the first accumulation of g^ravel around the lake of Sistan. Judging from the appearance of the lava cap of the mesa, it must be of approximately the same age as Kuh-i-Chaku. How long the process of uplifting the mountains continued or how widely it extended we do not know. The distorted shorelines which I shall presently describe show that warping continued till very recent times. To-day earthquakes seem to be unknown in Sistan, but Mr. Tate informed me that either Iben-i-Haukl or Iben-i-Batuta record the occurrence of one in the eleventh century. On the edges of the vSistan basin, however, earthquakes still persist. Two hundred miles to the south the smouldering volcano of Kiih-i-Taftan proves that the forces of vulcanism are still active ; while 300 miles to the eastward McMahon (a, p. 10) reports that earthquakes are common along a remarkable fault-crack which extends north and .south for 120 miles along the Afghan frontier between Kandahar and Quetta. It is highl)' probable that the basin of Sistan, like so many of the other basins of Persia, is being uplifted along the edges. The invasion of gravel in a thin sheet on everj' portion of the basin floor may be due in part to these mo\-ements. A detailed study of the thick gravels near Kuh-i-Chaku is difficult because of the extent to which the deposits are hidden by their own talus. Sections E and F, however, show that the gravels are interstratified with finer beds of silt, red for the most part. The alternating beds seem to be related in the same manner as the alternating clays below ; the gravels seem to occupy a place corresponding to the pink clays, while the silts correspond to the green lacustrine clays. The problem of accounting for the alternations in the upper strata is the same as in the clays, and the same reasoning applies. If our conclusions are correct, earth-movements, of which the \olcanoes were one manifestation, elevated the northwestern corner of Sistan, reviving erosion among the mountains and raising part of the bottom of the lake beyond the reach of the water. The clays of the lake bottom were exposed to erosion and certain layers were carried away, forming an unconformity, but soon abundant gravel was brought down from the renewed mountains and the whole country was buried in it. This must have happened during an interfluvial epoch, as appears from tlie gravels. A fluvial epoch then ensued, and, to use a word not recognized by lexicographers, the ungradation of the mountains was checked. The conditions of the fluvial epoch favored the preser\'ation of the graded slopes of the mature topography of the uplifted mountains, and the stripping which had progressed rapidly during the interfluvial epoch was retarded. Accordingly the materials brought down by the streams were fine-grained, and silts accumulated upon the gravels. Thus it seems probable the changes went on until three more were added to the ten fluvial epochs that had gone before. The evidence for these last three is not so abundant or conclusive as for their predecessors ; but three strong strata of gravel separated by finer material cap the bluffs in many places where no sections were obtained, and it is difl[icult to explain them otherwise. We rebel at the thought of adding epoch to epoch in such wholesale fashion, yet thirteen or a hundred epochs of climatic change are as reasonable as two. THE TERRACES OF SISTAN. 293 THE TERRACES OF SISTAN. NORTHWEST SIDE OF THE r,AKE. In Sistan lacustrine and fluviatile terraces merge into one another, but cause no confusion, as they both tell the same stor)'. Scattered among them and often parallel to them are numerous structural terraces, due to the hardness of the gravel among the upper and of the green clay among the lower strata. Most careful work is needed to avoid confusing them with their neighbors. A fourth class of terraces is due to warping. None of these has been detected, but the older lacustrine terrace has been warped, and the corresponding stream terraces must have been similarly affected. The lacustrine terraces agree with those of fluviatile origin ; two are well devel- oped, and a third is now in process of formation. They indicate that since the last heavy gravels were deposited on the smooth plain which caps the upper terrace (fig. 169) the lake has stood at three different levels, at two of which it has cut high bluffs in the soft clays or formed large beaches where the shore is less steep. The bluffs are best developed on the northwest side of the lake. At Bereng, where there has been no warping, the two upper levels are about 15 and 25 feet above the level occupied by the lake surface of January', 1904, which was perhaps 5 feet lower than the extreme high level of floods. Just north of Bereng all the space between the 15-foot beach and the present beach is covered with beach material, and the same is tnie wherever the shores of the lake are fairly steep. Where the shores are flat, on the contrar)-, the two beaches are sharply separated. The 15-foot beach appears to be parallel to the present shoreline. The 25-foot beach, on the contrary-, has been warped up to a height of 300 feet. At no time, apparently, did the lake level reach any great height, for even a rise to the 15-foot level would mean that the lake of Sistan must permanently overflow to that of Zirrah, and a rise to 25 feet would cause the two lakes to coalesce into one and would invoh'e an immense increase in area. The recent histon,- of the lake resolves itself into a few simple changes. At the time of the volcanic eruptions of Chaku the lacustrine deposits at tlie northwest corner of the Hamun-i-Sistan and along the western side had been uplifted and covered with layers of gravel and silt. The gra\-el layers appear to ha\-e numbered two before the eruptions began and one during their progress or after their comple- tion. When the deposition of gravel came to an end a vast and vev}- smooth gravel plain (I, fig. 169) surrounded the Hamun and concealed a series of lacustrine deposits, very complete at the north, but worn away by the Bendan stream at the south. At Chaku the plain stood several hundred feet higher than the lake, although not so high as at present ; at Bereng it stood at the level of to-da}-. When matters were in this state the lake stood at the 25-foot level (A, fig. 169), and remained there long enough to form bluflfs on all sides of tlie lake. Near Chaku these are 500 to 600 feet high and are capped with lava ; toward the south the)- gradualh' descend till at Bereng they are but 20 or 30 feet high. At Daghaz the bluffs still border the lake and are being actively undercut. The)' present an almost perpen- dicular cliff 100 feet high. From here northward they gradually retreat, and at the same time grow higher, till at Chaku the)- are 3 miles from the water. Where 294 THE BASIN OF EASTERN PERSIA AND SISTAN. there is no lava cap the upper portion of the bhiffs is broken into three smaller terraces (x, y, 2, fig. 169), due to the alternate strata of gravel and silt, while lower down the hardness of the green clays causes minor benches. As viewed from below the crest of the higher bluffs sometimes shows its true flat-topped character, but oftener it appears like a jagged range of high hills. Below the ragged terraces of the dark gravel cap the softly outlined but steep slopes of the beautifully tinted clays spread into fine sprawling spurs, separated by cleft-like gorges and buttressed with round greenish bastions where the harder, uuweathered lacustrine clays fonn terraces. At the base of the cliffs outstanding portions of clay fonn graceful pj-ramids or domes, soft in outline and banded with harmonious colors — pale-pink, green, yellow, and purple, which ])lend insensibly one into another. After the cutting of the first shoreline, the lake fell and perhaps became dry during an interfluvial period. When next we have a record the water stood at B (fig. 169), and again cut a bluff, low and insignificant where it stood below its pre- decessor at Bereng, for example, but higher where it completely undercut the latter. T 1( , ,^ \5_m =N-S>-.»>^„-U'5-s:ia^ .. issEisaiSffis^^ _ ism^sin^issi^ \ LaJte _____^^--__^-_^-_^^__-_— ___ — Fig. 1 69. — Ideal Cross-secrion of the Lake Terraces and Bluffs on the Northwest Shore of the I-.ake of Sistan. as at Daghaz. North of this latter point a great change had taken place since the fonnation of the earlier bluffs. The whole country had been uplifted to a height which reached a maximum of 300 feet at Cliaku, as shown by the height of the older shoreline. Probably the elevation was in progress during the earlier fluvial as well as during the interfluvial epoch, for the terrace-top below Chaku slopes more steeply than would be the case if it had all been produced by water standing at a single level. At present the lake is cutting insignificant bluffs or depositing beaches. Thus, on the northwestern shore of the Hamun-i-Sistan, we have a record of two fluvial or lacustral epochs and two interfluvial epochs. During the first the water stood approximately 25 feet higher than now, and remained there long enough to cut verj- far back into the surrounding country. Toward the end of this epoch the region around Chaku began to rise. Then came a time of falling water, and, by inference, an interfluvial epoch, when the lake became almost dr}-. When the water again rose in the succeeding fluvial epoch the movements of uplift had almost come to an end and the land stood in practically its present position. For a second time bluffs were cut. The level of the water was but little higher than to-day, but the area and hence the volume of the lake must have been vastly larger; lastl\-, the water fell to its present level, and is now fonning an insig- nificant strand. This strand, however, lies higher than the level where most of the lake's erosive action takes place at present, and it seems probable that the level of the water is now falling. THE TERRACES OF SISTAN. 295 SODTHBAST SIDE OF XHB I,AKB. On the diametrically opposite side of the lake, along the southeni border of the Helmund delta, a number of beaches and bluffs confinn these conclusions. Certain features stand out clearly, and may be classified according to age : (a) Modem shore- lines ; (^) younger abandoned shorelines closely connected with fresh bluffs; (c) older abandoned shorelines with weathered bluffs. Modem shorelines. — The modern shorelines are e\'erywhere weak, and in many places where the shore is flat and marsh)- they are quite indistinguishable. The lake can not have stood long at the present level, for if it had the present shorelines would be more pronounced. The water appears to ha\e fallen gradually to its present position, as is shown by the character of the beaches which inter\-ene between the present water-level and the 15-foot level. Where the shores are some- what steep the weak modern beach appears as the lower member of a series of small beach ridges which culminate in the well-developed 15-foot beach. Where the shores are flat and are not closely bordered by blufis the older beaches diverge from the present lake shore, and are more clearly differentiated. YoiDiger abandoned shorelines. — (/) Lidtick. — Three older beaches were seen which clearly belong to a time when the lake stood higher than now. Their e.xact level in reference to the water could not be ascertained, but it is certain that they lie beyond the reach of the lake to-day. In the first place, many culti\-ated fields, and even villages, lie between the beaches and the lake ; and, in the second place, the beaches are covered in part with large sand-dunes which could only accumulate after the water had retired. The beach which lies nearest the lake was seen at Lutuck, half-way from Devletabad to Vennal. Here the delta plain ends in low east-and-west bluffs of the the usual banded clays capped with gravel. From the foot of the bluffs what appears to be an old beach diverges northward. It has now been transfonned into a strip of low sand-dunes which cover a breadth of from 25 to 50 feet, and rise to a height of 5 feet. No pebbles or fossils were found. Farther south along the base of the cliffs this beach could not be distinguished. Beyond Vermal, however, there is a strip of sand which has the character of a beach without the relief. Where an irrigation canal has been dug through this the sand was found to be full of small bi\'alve shells like those found in the beaches next to be described. {2) The Seh-Kuheh beach and bluffs. — Two or three miles southeast of Seh-Kuheh and from 5 to 7 miles from the lake, there is a much better example of a shore- line of the same kind as that at Lutuck. It consists of the line of fresh bluffs from which sections M, N, and O, plate 5, were taken. At their foot lies a ridge of huge sand-dunes (fig. 170), half concealing a beach composed of sand, fine gravel, and bivalve shells like those of \'ermal. About 2 miles from Seh-Kuheh the beach leaves the foot of the bluffs and runs northwestward between Seh-Kuheh and the lake. It takes the same fonn as the beach at Lutuck — a long line of sand blown into dunes by the wind. It is not impossible that the two beaches are of the same age, although I am inclined to believe that the Lutuck beach belongs to a slightly later stage of the lake's history-. The exact age of the Seh-K\iheh beach can not be detennined by phj'siographic evidence, but it is at least evident that the water stood upon it ver>' recently. This 296 THE BASIN OF EASTERN PERSIA AND SISTAN. is shown by the bUiffs (fig. 170). Wherever they are fronted by a beach they are extremely fresh, as though the waves had been at work on them btit yesterday. Their tops present a clean, sharp angle and are little dissected, and their slope is almost perpendicular. Yet the material of which they are composed is by no means resistant and contains many sandy or silty portions which are subject to rapid degradation. Moreover, the beach is also fresh and is not concealed by talus from above. Where the beach and the bluffs diverge the character of the latter at once changes. They become rounded and well dissected, a sloping body of talus lies at their base, and the cliffs slope so gently that thej- are covered with gravel and waste derived from the battered tops. The beaches and the fresh bluffs can not be old. The accuumlation of sand at the base of the latter is of very recent date. The large Fig. 170. — Lacustrine Bluffs and Recent Sand-dunes near Seh-Kuheh. View to the northeast. dune shown in the illustration (fig. 1 70) is said by the natives to have accumulated in three years. Under it are seen the cross-bedded remains of older dunes which have been repeatedly formed and swept away. Under the lowest of them, and rest- ing upon the old beach, I saw the ruined mud walls of an ancient garden. This is said to have belonged to a certain Rustum Khan, who died a hundred years ago. It is clear that the accumulation of the dunes is the work of a comparatively short time, probabh- not more than two or three hundred years. Moreover, it is probable that the accumulation of the dunes would begin within a relatively short time after the retirement of the water. Accordingly, from the recency of the sand-dunes and the freshness of the beach and bluffs, I am incliued to believe that the lake stood at the level of the Seh-Kuheh beach at a date which is to be measured in hundreds THE TERRACES OF SI STAN. 297 rather than thousands of years, and which falls well within historical times. It is probable, as will be shown later, that the lake has stood twice at this level, but this inference is based on historical rather than physiographic evidence. This level seems to be that at which the lake would permanently discharge to the God-i-Zirrah through the Shila. Therefore the lake might be expected to return to this position whenever it was abundantly supplied with water. (j) The Sabazkim beach and bluffs. — The most remarkable of the old beaches of Sistan lies in the northward-facing bay of Sabazkim, a mile and a half south of Aliabad, on the road from Seh-Kuheh to Kohuk. It is situated 12 miles from the lake, and is elevated but little above it, standing probably at the 15-foot level. When the water filled Sabazkim Bay it must have covered most of that part of the Helmund delta which is to-day most thickly populated, although the ridges occupied -«N > ■ » '1 ^>--^ "li^l*.*- -K^— ' "^ •^-- •"■-■A^i '^ t- - - - - -^^» Fig. 171. — Abandoned Beach and Lacustrine Bluffs at Sabazkim. At the base o( the bluffs sand-dunes are accumulating. by Zahidan and most of the other ancient ruins were probably out of water. The shape and position of the bay exposed it to the full force of the waves and currents generated by the fierce north-northwest "Wind of One Hundred and Twenty Days," and the result is seen in the size of the beaches. At the base of the highest of the Sabazkim bluffs, where the British Arbitration Commission has set up a monument, there is a beach, over 500 feet broad, with a rise of 20 feet (fig. 171). At the top of the beach rise large sand-dunes like those at Seh-Kuheh, and behind these a ver}' freshly eroded cliff rises almost perpendicularly to a height of no feet (see section P, plate 5). The upper part of the beach is composed of fine gravel, the middle part of small cobble-stones and sand, and the part far out toward tlie lake of sand. Ever\^where the beach is crowded with shells of four or five kinds, of which 298 THE RASIN OF EASTERN PERSIA AND SISTAN. two, a clam and the pink mussel already mentioned, are said by the natives to still live in the lake. The others may also exist, but are too small to be noticed, except by the scientist. At present, however, the amount of life in the lake is so small that I did not once see any living creatures or even any shells of those that had recently died. This decrease in life is the natural result of the drying up of the lake. When the water stood at the higher levels and was always abundant, conditions were favorable for plentiful lacustrine life; when the water decreased and actually dried up, as in 1872, most of the animals perished. Fig. 172.— Old L.ake Beach at Sabazkim, looking West. TTie lake stood on the right of the beach and a lagoon on the left. Near the middle of the bay of Sabazkim the beach and the bluff part company. The cliff bends southward and at once loses its steep, freshly-cut appearance and becomes like the corresponding cliff at Seh-Kuheh. The beach assumes the fonn of a gravel ridge from 10 to 15 feet high and as level as a railway embankment (see fig. 172). It continues unbroken for a distance of 4 or 5 miles and po.ssibly Xdke >~^~^Xaffoon Fig. 1 73. — Ideal cross-section of the old Lacustrine Beach at Sabazkim. farther. In cross-section (fig. 173) it shows several ridges thrown up when the waves were at different heights. Every-where, even in the coarse gravel, shells abound. Between the beach and the cliffs to the .south there is a broad lagoon. This is bordered by worn, battered cliffs, at the base of which lies a small beach which was probably formed before the waves had built the larger beach which now cuts off the lagoon. THE TERRACES OF SISTAN. 299 Older abandoned shorelines. — Traces of the older lake level were not found in great abundance on the southeast side of the lake, although there were enough to prove that they exist. At Lutuck the lower bluffs are capped by a narrow plain or terrace about 15 feet, possibly more, above the r 5-foot beach. From this rises a second line of bluffs much more worn than any of the lower ones and well sheeted over with gravel, so that the>- present a slope which a horse or even a camel can ascend. At Seh-Kuheh and Sabazkim there are similar old bluffs. Those at Sabazkim are shown in the sketch (fig. 174). From either side of the central bluff MAUN LAKE -BED o Aliatoad o|w^^\ Fig. 174.— Sketch Map of the Ancient Shore features in the Bay of Sabazkim. a wing of terrace branches off at a height of about 30 feet above the 15-foot beach. The foot of the upper terrace seems to represent the position of the lake at the time when the 25-foot beach was formed in the neighborhood of Bereng. Apparently here, as at Kuh-i-Chaku, warping took place between the last two fluvial epochs. COMPARISONS. A comparison of the lacustrine terraces of Sistan with those of other regions described in this \olume shows that in each case there were two epochs of high water preceding the present epoch of low or medium water. At Shor Kiil, in Chinese Turkestan, at the playas of Khaf and of Kulberenj and at Sistan precisely the same phenomena are repeated. In the latter case we should not expect more than two lacustrine terraces, because of the movements of the crust which have interfered with possil^le records of older lake levels. In the other cases, however, a greater number would be expected to agree with the number of glacial or fluvial epochs of which there is evidence in neighboring mountains or valleys. It seems prob- able that the iuterfluvial epoch preceding the fonnation of the first terrace was of unusual length, or of unusual character in some respect, so that traces of earlier lacustrine action were destroyed. Such a supposition is supported b)- the great gap which we have seen to exist at Kogneh and at Bajistan between the tsvo lower terraces and those above them. 300 THE BASIN OF EASTERN PERSIA AND SISTAN. Extinct lakes are a feature of many of the chief playas of the Iran basin. At Mashkel, south-southeast of Sistan, in the continuation of the Afj^han depression, the plaj'a seems to be surrounded by terraces in the same way as the playa of Khaf, so far as can be judged from the brief notes of MacGregor (pp. 128, 129, 134) and others. Farther to the east, in the center of northern Bahichistan, tlie Lora Hamun, as described by Vredenburg (pp. 210-21 1), "is now a large playa entirely dry most of the time. In it are islands of lava rising to a height of 50 feet, more or less. They are surrounded and even covered by pale-yellow silt of just the same sort as that which forms the floor of the playa. The lower portion of these mud deposits, though ravined by the rain, still presents a terraced outline, and denudation has exposed sections in which strings of angular pebbles from the tuffs of the hills rest iipon strata of the buff-colored mud. It is quite evident that this mud, washed down in former times by rivers, was deposited in the still water of a lake, just as the deposit of the same nature which co\-ers the dried-up floor. Moreover, as they are found at all heights along the slopes of the hill, it shows that these were at that time entirely submerged ; further, that a large sheet of water then existed whose surface rose to a height of 50 feet or more above the floor of the dried-up lake, and that the Lora Hamun covered a surface three or four times as extensive as the plain which now bears that name." In the same connection Vredenburg (p. 210) says that throughout all the confusion of the volcanic mountains, interrupted drainage, and smooth playas of northern Baluchistan "there are some curiously regular features. Such are the long lines of terraces formed by the conglomerates (/. ' time. Thus interpreted the recent geological history of Persia begins with an arid climate at the end of the Tertiary era, after which ensued a fluvial period composed of some fifteen fluvial epochs of prolonged rivers and expanded lakes, separated by inter- fluvial epochs of shortened rivers and diminished lakes. The fluvial epochs increased in frequency and possibly in length and intensity from the beginning up to about the middle, after which they decreased. The evidence for these many epochs is of varying degrees of validity, and increases in certainty from first to last. The two lacustrine terraces of the various lakes and playas indicate two recent fluvial epochs. The kind of evidence and the method of study are of a sort which is ever)' where familiar and which has been successfully tested in many cases. The three preceding epochs rest on less effective evidence. The evidence for them in the three gravel strata at Sistan is not in itself conclusive, since it consists of but two or three sections ; and the warping and volcanic action which are known to have been taking place at the same time may have influenced the deposition of the gravels. Never- theless, the widespread occurrence of a series of five terraces in other localities, and the impossibility of explaining these except on the climatic theory, give a fair degree of reliability to the conclusion that three more severe fluvial epochs preceded the two recorded in the lake shores. The test of this conclusion lies in a further study of those regions where, according to theoretically deduced consequences, similar terraces ought to be found. The remaining ten epochs rest confessedly on a small basis of fact. It has been sunnised that the glacial period may have consisted of an increasing series of climatic changes preceding a decreasing series, and there is evidence that the exten- sion of the ice during what is commonly known as the second glacial epoch was greater than during its predecessor. Further than this, however, so far as I am aware, no one has ever gone. The facts of Sistan seem explicable only on the theory of a large number of increasingly severe fluvial epochs followed by an approximately equal series of decreasing epochs. This is at least a fair working hypothesis. To test the theory is difficult in the ver}- nature of the case. Yet it can be done. In the first place, a far more extensive study of the abundant deposits of Sistan is practicable to-day, and it is only a matter of time when it will be 302 THE BASIN OF EASTERN PERSIA AND SISTAN. possible to enter Afghanistan and study the lacustrine clays which are reported to lie far up the Helniund. It is not impossible that other localities may be discovered where the bottoms have been lifted up and exposed to view {e. g., Chahek, p. 267), but none is likely to be found where a greater harvest of facts can be gathered than at Sistan. There is also a way in which the theory can be tested nearer home. If the glacial period in all parts of the world consisted of an increasing and a decreasing series of changes, the bottoms of such lakes as Bonneville and Lahontan must preserve the record. Some day it will be possible to investigate the dry beds of these lakes by borings, and the tlieor>' can be adequately tested. CLIMATE AND HISTORY. In the concluding section of this report I shall deal briefly with the main object of our expedition, to which the preceding sections have been tributary. Iran is one of the countries which will most readily furnish an answer to the question of the relation of history and physiography, for the country has been inhabited by man from remote antiquity. If man inhabited the earth during the later glacial or fluvial epochs, Iran would probably have been peculiarly favorable to his development by reason of the relatively warm climate and moderate degree of rainfall which it appears to have enjoyed. A few facts bearing on this subject may indicate the line along which a solution of the problem will perhaps be found. History, archeolog}', and tradition all present certain features which seem to point to a greater rainfall in antiquity than at present. Physiographic evidence points in the same direction. The question is : Do the two sets of facts show points of contact, and does the same theory explain them all } THE ANCIENT CLIMATE OF IRAN. Many writers on Iran have referred to the possibility that in antiquity the rain- fall of the country was greater than now. For instance, Blanford {a, p. 500) states that " from the accounts given by ancient writers it appears highly probable that the population of Persia was much greater and the cultivated land far more exten- sive 2,000 years ago than at present, and this may have been due to the country' being more fertile in consequence of the rainfall being greater. Some alteration may be due to the extirpation of trees and bushes, the consequent destruction of soil, and increased evaporation ; but this alone will scarcely account for the change which has taken place." Sykes (p. 364) expresses the same opinion : "Alexander's march with a large army and a huge camp tends to show that Asia was, in his day, not so arid as at present, and it would seem possible that in a sense my observations in Sistan support this contention." In various places he elaborates this view and presents other e\'idence. The Rakshan Valley, for instance fpp. 234-235), in western Baluchistan, 300 miles southeast of Sistan, is a stream of exceedingly salt water flowing in a wide, shallow valley and discharging into the Mashkel River. The marches up this valley were " intensely monotonous, day succeeding day without a sign of life being anywhere visible, yet we could interest ourselves by speculating on the causes that had swept away the population from this \'alley, which for mile CLIMATE AND HISTORY. 3O3 after mile was carefully terraced, while here and there were mounds littered with pottery. War, no doubt, has had much to do with it, but even more probably ruth- less deforestation in this and adjacent districts had decreased the rainfall, after which the springs dried up and the population was driven away." Holdich, speaking of the swamp of Mashkel, which lies in the same part of Baluchistan, but a hundred miles nearer to Sistan, remarks : Tliis extraordinary abundance of water locally is difficult to explain. It appears to be a survival of a far more extended condition of water-supply in southern Baluchistan than now exists. There is widespread evidence of former cultivation by an elaborate system of irrigation in so many parts of southern Baluchistan, where it is vain to hope that such cultivation will ever exist again, that it seems as if some mighty change must have come over the land thus to render so much of it water- less. It may be due to forest denudation and cessaition of rainfall, but, more likely, it is due to the gradual exhaustion of those subterranean sources which seem to be still prevalent in more north- ern districts. In speaking of the mountains of Kharan, 100 or 200 miles east of Mashkel, in the center of northern Baluchistan, Vredenburg (p. 2 13) comes to a similar conclusion : In all the valleys round Zara there are to be seen hundreds of s.tone walls which are called " gorband," or " dams of the infidels." Sometimes they stretch right across the flat, pebbly floors of the great valleys, which, for want of a better name, are termed " rivers." They also occur across the entrance to most of the tributary ravines and at various heights above the main valley. The country is quite uninhabitable for want of water, and yet there is no doubt about the nature of these walls, which are similar to works erected to the present day in many regions of Baluchistan and Persia, being, in fact, nothing but terraced fields. In many cases they still hold back the soil, for- merly cultivated, which has been heaped up against them. . . . The absence of any canals, the great height to which the walls are found up the tributary ravines, show that the fields were not watered by means of some general scheme of irrigation with canals deriving their supply from some reservoirs placed at a greater altitude. Perennial springs, now everywhere dried up, must have existed in all the ravines where these remains are found, which shows how much greater the rain- fall must have been formerly. From the evidence of certain tombs Vredenburg thinks that the fields were in use even down to Mohammedan times. Alexander's march. The march of Alexander from Mesopotamia across Persia to Samarkand and the Jaxartes River, and thence via Bactria to India and back through Baluchistan to Persepolis and Babj'lou, is justly regarded as one of the most remarkable feats in histor}'. There have been innumerable discussions of the subject, and the general tendeucy, especially of those writers who have actually traversed the more remote routes followed by the conquerer, is to think that under present conditions the march would have been impossible. This is not the place to discuss the whole question, but a few remarks tipon the portion of the journey nearest Sistan mav not be out of place. When Alexander left India he divided his army of 1 10,000 men into two parts, one of which, including the elephants, the invalids, and the heavy baggage, was put under the command of Krateros, and followed a route through southern Afghanistan and Sistan. Alexander himself, as Sykes says (p. 169), "faced the horrors of the desert by the route along the coast of Baluchistan in order to suppl)' his fleet by means of his army," although Arrian says it was because of his wish to rival the journeys of Scmiramis and Cyrus along the same road to India. 304 THE BASIN OF EASTERN PERSIA AND SISTAN. The route wliich he followed is exceeding;ly difficult even for a small and quickly moving caravan; and for an annysuchas that of Alexander, which is stated to have been accompanied by women and children, the hardship must have been incredible. St. John (a, p. 75) is of the opinion that " in the early part of his march through Baluchistan, Alexander must .... have been deceived by his guides, who seem to have kept him at exactly that distance from the coast where there is least water." Farther west, in southeastern Persia, conditions were scarcely better. Sykes, who is the latest authority on this region, speaks of it as follows : "During my journey from Chahbar to Ceh, in October, 1893, which was also the time that the Greek army traversed Makran (/. e., southeastern Persia and south- western Baluchistan), the temperature in the shade was generally about 100 degrees, while water was almost nonexistent, and what little there was we could hardly drink (because of the salinity)." (P. 171.) " Throughout the journey (from Chahbar to Kirman during the months from October to June, 1893-94) forage was our chief anxiety (although the caravan numbered only from a dozen to twenty men)." (P. 1 12.) Among the higher mountains'of this corner of Persia water can usually be found by digging in the water-courses, although it is very poor and scarce (p. 113). Forage, however, is always hard to obtain, and (p. 123) the governors-general of the province practically never visit the district becaiise of the scarcity of su])plies. Yet Alexander nnist have crossed it with a large anny. Northeast of Bampur, even in March, when vegetation is at its best, forage was so scarce that the governor-general, whose guest Sykes was, had had a supply stored at ever}- stage (p. 144). " This desert stretch of more than 150 miles " along the north side of the Jaz Morian swanip was once thickly populated, as is shown by numerous ruins, and by the remnants of kanats or underground canals, to the reported number of 200, which are now drj-. Many of these canals have probably been abandoned because of wars, but that does not explain how Alexander procured water for an army where there are now merely salt pools, nor how he procured forage for all his baggage animals where to-day a few score can barely subsist. (See plate 4.) The division of Alexander's army which marched through Afghanistan under Krateros appears to have had no special difficulties, for Arrian, the historian of the expedition, merely remarks that "when Alexander arrived in Kirman, Krateros joined him, bringing the rest of the army and the elephants." (Quoted by Sykes, page 174.) Apparently Krateros went via Quetta to Kandahar, and thence his route is agreed to have been down the Helniund to Sistan. So far the line of march would present no insuperable difficulties even to-day, although Bellew (p. 182), who followed the same route, relates that where the road made a detour to get around an impassable portion of the river valley, some of his men nearly died of thirst on the hot gravel plain. Beyond Sistan Krateros's route led across the southern end of the Dasht-i-Lut to Narmashir. As St. John says (a, p. 75), " it would certainly puzzle a Krateros nowadays to march his elephants and heavy baggage from the Helmund to Narmashir; but there is everj' reason to suppose that part of Persia to have been far better populated and better watered than it is at present." The greater part of the distance of 180 miles from the borders of Sistan to Nannashir is the most absolute desert, either waterless or supplied with the most brackish wells. CLIMATE AND HISTORY. 305 Nasratabad, the one village, could hardly give supplies for a hundred men, and even.-thing for an army would have to be brought from Sistan. Yet the route was once so important that strong fortifications, caravanserais, and other ancient ruins occur at frequent intervals, as do also kanats or canals. Of the last 90 miles Smith (p. 248) says that at both of the two possible stopping-places "water was obtainable by digging wells 5 feet deep, but it was brackish and bad ; and at the latter place there is a stream so salt and bitter that none of our animals would even touch it." Sykes (a, p. 417) describes the same route in equally uncomplimentary terms: Gurg (th« first stage) is generally considered to be the worst stage in this part of the desert, the pools of water being quite iindrinkable. ... In summer, owing to the heat, Gurg is little better than a death-trap, and here, more than elsewhere, the abomination of desolation is realized. . . . At Shurgaz (the next stage) the water was just a little better, but so scanty that there was none for the camels. At the end of the third da}', after marching over a hundred miles through the worst part of the desert, a better region was reached. "A day's halt was impera- tive, as our camels could hardly move." That a large army could cross such a desert is hardly credible ; that such an army should have no hardships worthy of mention by the historian is less credible ; and that they could bring elephants with them is least credible. The elephants of Krateros are not the only ones mentioned in history. Mal- colm (I, p. 35) speaks of them as abundant in antiquity in the kingdom of Persia, as is shown by both the ancient history and the sculpture of the country'. Mazan- deran is the only part of the countrj- that could now support them, but they are spoken of in other places. Another interesting commentary' on the climate of antiquitj' is afforded by a comparison of a description of the province of Kirman as it is to-day, by Sykes (p. 44), and as it was in the past b}- Strabo (quoted by Sykes, p. 48). The modern description runs : " The whole province can best be described as partly desert, pure and simple, and partly desert tempered by oasis. ... As may be supposed, the ri\ers are imimportant." The ancient description is scarcely longer, but conveys a wholly different impression : " Kirman . . . lies more to the north than Gedrosia. This is indicated by its fertilit)-, for it not only produces ever)thing, but the trees are of large size. . . . It is also watered by rivers. ... It includes also a desert tract which is contiguous to Parthia." Even since the twelfth ceuturj- there has been deterioration, for in ninnerous cases ancient Mohannnedan towns are abandoned and can not be restored because no water can be procured. THE DESICCATION OF ANCIENT RUINS. The ruins of E^asteni Persia and the neighboring countries are incredibly abundant. The mighty cities of the dead crowding the shores of the lake of Sistan in the center, and the abundant vestiges of a fonner population much denser than the present in Kirman to the west, Baluchistan to the south, and the Helmund Valley to the east, have already been mentioned. E.xamples might be multiplied indefinitely, for the tale of ever}- traveler is full of them. North of Sistan the same is tnie. Half-way from Herat to Kandahar the plain of Dasht-i-Bakwa, where, according to 306 THE BASIN OF EASTERN PERSIA AND SISTAN. an Afghan prophecy, a great battle will some day take place between the English and the Russians, is now inhabited only by nomads, althongh this has by no means always been the case. Yate (p. ii) " found the plain covered with the marks of old karezes, or underground water-channels, and it had evidently been thickly populated by a culti\ating cla^s at some time, while water was said to be obtained all over it. When I passed it was all a waste." Ferrier, in the same region, describes the ruins of city after city. To a certain extent these might be restored to prosperity under good government, but there are certain places which no amount of government, good or bad, could affect. NEH. The ruins of Neh, called Kala Shah Duzd, or the Castle of King Thief, illustrate this point admirably. They are located 60 miles west of the northern end of the lake of Sistan. They have been described by Sykes (p. 413), who says : "Neh ... is undoubtedly a site of great antiquity, and must have been a place of impor- tance. ... Art the present time nine routes radiate from the town. Ancient Neh . . . three miles to the east of the more modern fort, is built on a hill only accessible on the west side, and is carefully guarded by ... a line of ba&tioned wall. . . . Lying up the steep hill- side are thousands of houses, built of unihewn stone fitted together with mortar the summit being some six hundred feet above the plain. The other faces are perpendicular, but the water supply seemed insufficient, there being only tanks, so far as could be seen. The area covered was quite four acres, and these are certainly the most important ruins which I have examined in East- ern Persia." It seems to me that Sykes, who is usually very accurate, has overestimated the size and importance of the ruins. I estimated that there were at least 300 houses still standing, possibly 500, and there may have been as many more which have fallen. As to the paucity of the water-supply, these questions seem to be not whether there are cisterns enough, but how the cisterns were filled. I counted five large cisterns, all of them located near the top of the hill. One was located in the mouth of a small valley, where it might possibly be filled .several times in the year if the drainage from among the surrounding houses were allowed to pour into it. The others were placed at the very crest of the hill, where they were not only surrounded by houses, but had only the most limited drainage areas, so that the rainfall of a whole year under present conditions would hardly fill them, even if the drainage firom the streets were allowed to come in. If the place were simply a fortress we might suppose that water was laboriously carried up the steep hill from the plain 600 or 700 feet below and stored for time of need, although there is now no source of water within 2 or 3 miles. The number and pennanence of the houses and the fact that many of them lie outside the fortifications, even though there are open spaces inside, indicate that the place was a pennanent town. If the inhaljitants were agriculturists their fields must have been far away ; if they were artisans and tradesmen their number is surprisingly large in proportion to the present possibilities of the surrounding country. If the rainfall were greater there would be no difficulty in understanding the location of Kala Shah Duzd, for the cisterns could be filled, fields could be cultivated nearby, and the surrounding plains could support villages which would warrant the building of a large fortress and town. It is not absolutely impossible that such a place should grow up under CLIMATE AND HISTORY. 307 existing conditions, but it is highly improbable. Ancient Neh is one of many places which are hard to understand unless we suppose that some radical change of conditions has taken place. THE MERV OASIS. In this connection two other places farther north in Transcaspia deserve men- tion. One of these is the ancient city and oasis of Merv, which I have described in a short report which will be published among the archeological reports of the Pumpelly Expedition to Turkestan for the year 1904. A study of the distribution and extent of the ruins which cover the oasis indicates that in antiquity the extent of land under cultivation and the number of inhabitants were not only greater than at present, but were greater than would at present be possible, even if all the water of the Murg-ab River, which sustains the oasis, were utilized with as much care as is employed upon the experiment station of the Imperial Domain. It is difficult to account for this unless the water-supply was formerly greater. BAI, KUWI AND ANAU. The other Transcaspian example is at Anau, near Askhabad. The main features of this place, both modem and ancient, will be described in the forthcoming arch- eological reports of the Pumpelly Expedition. At Bal Kuwi, in the desert about 10 miles north-northwest of Anau, lie the ruins of an ancient nnid village. The main site consists of a mound perhaps 15 feet high, ver)- broad and flat, and co\-ered with bits of pottery. Where not buried in sand-dunes the surface of the mound shows the rectangular outlines of houses, the roofs of which have disappeared, while the walls have been buried to the top in the pink .sand of the desert, and are thus pre- served with their tops flush with the surface. Excavation shows that these houses are built without a trace of wood. On the floor of each room is a foot or two of loose cla)', half of it in the fonn of sun-dried bricks, which appears to be the debris of the roof Apparently the houses were made entirel\- of mud, with domed roofs, like those of modem Persia. The total number of houses in the main village may be estimated at from 75 to 150, while half a mile away, at Telbeng Berkoh, are 20 more of the same kind. The date of the mins is unknown, and so far as the style of architecture and the kinds of pottery which are found in the houses are concerned, they may belong to any epoch within the last two thousand years. The Turkoman graj'-beards have no tradition on the subject and merely say that when they came to the country fiftj' years ago the ruins presented the same appearance as now. The inhabitants of the ruins were probabl}- tillers of the soil, for the houses are per- manent structures, and their number, at least 75, is so great that they can hardly have been occupied by a ])astoral people. At present there are three wells at Bal Kuwi, and 20 families of Turkomans camp there for three months in the spring. They say that there is grass enough for nine months, but as it gets dry they move awa}-. Even allowing for understatement by the Turkomans, it is hardly probable that 75 and probably more families could be pennanently supported by flocks in a region which the present inhabitants consider only sufficient to support 20 families nine months out of each j-ear. If the inhabitants of Bal Kuwi were not pastoral, they 308 THE BASIN OF EASTERN PERSIA AND SISTAN. must have been ag^ricnltural, but agriculture is to-clay impossible in the neighbor- hood of their village. In the first place, more than half the region round about is covered with sand-dunes. In the second place, irrigation is impossible, and with- out irrigation agriculture is utterly impossible, as the Turkomans know to their cost. P.al Kuwi lies in the course which the Anau stream would pursue if it should be prolonged. At present, however, even in the greatest floods, when no water is taken off upstream for irrigation, the floods are lost in the desert before coming half-way from Anau to Bal Kuwi. Between their point of disappearance and Bal Kuwi lie some miles of sand-dunes, through which it is evident that water never pa.sses. In brief, Bal Kuwi appears to have been an agricultural village, but under present conditions that would l)e impossible. If in some way the Anau stream could be caused to increase its volume so as to flow farther out into the de.sert, the old condition might be restored. Bal Kuwi seems to be a parallel case to Shah Duzd and Merv, and to many other ruins in this part of the world. THB NORTHERN BORDER OF THE DASHT-I-LUT. One more illustration will suffice to show the uniformity with which depopu- lation has gone on over the whole of Eastern Persia and its neighbors. Lord Curzon (p. 255) made a rapid journey along the high-road from Meshed to Teheran, which skirts the northern border of the great Persian de.sert. For the entire distance of 560 miles there is frequent and ahnndant evidence that the country traversed was once more densely or less sparsely populated, and for that reason more carefully tended, than it is at present. The traveler passes towns which have been entirely abandoned, and display only a melancholy confusion of tottering waJls and fallen towers. He observes citadels and fortified posts whidi have crumbled into irretrievable decay and are now little more than shape- less heaps of -mud. He sees Jong lines of choked and disused kanats, the shafts of the underground wells by which waiter was once brought to the lands from the mountains. The waJls of the cities are in ruins and exhibit yawning gaps; the few public buildings of any note are falling to pieces; rows of former dwellings have been abandoned to dust-heaps and dogs. From other more detailed accounts of this same region it appears that the niins are of all ages, from two thoti.sand to twenty years, and that the country has been subjected to a gradual proc&ss of niin and depopulation. Practically all writers on Persia agree that in the time of r3arius and as late as early Mohammedan times the countrj- was decidedly more prosperous and more populous than now ; and the area of cultivation and the visible supply of water in canals and kanats, or under- ground channels, were much greater. THE CADSE OF THE DEPOPULATION OF IRAN. Several theories have been advanced in explanation of the gradual ruin of Persia and its neighbors, but all of them can be summed up under two. According to one school, in which Curzon is the most prominent writer, the climate of Persia has remained practicallj- unaltered throughout historical time. The decay of the country is due to wars and massacres and the frightful misgoveniment which has prevailed centurj' after century. If a strong, just government were established the fonner conditions of prosperity would be restored. The progress which has been made under British rule in the arid portions of India and under Russian rule in CLIMATE AND HISTORY. 309 Transcaspia shows what can be done. The other school, of which Blanford is the best-known representative, holds that dnring the last two thousand years the climate nmst have changed. Wars and nii.sgovernment have been a fearful curse, but their influence is not sufficient to account for the location of large towns in places where to-day a caravan can with difficult}- find a pool of brackish water. The just rule of a European power may do much in favored localities, and it would be an immense blessing ever)where ; but it can not restore the ancient prosperity. It is not my purpose to enter into an exhaustive discussion of these two opposing views, for that would lead into a consideration of the causes of wars and migrations, the reasons for the fall of nations, and the philosophy of histor}'. I shall merely' state a few salient facts which may be put in the fonn of answers to the following questions : (a) Do wars and misgovernment necessarily cause pennanent depopulation ? (d) Are Eastern Persia and its neighbors able to support a much larger population than that which now occupies them ? (c) Is there any independent evidence that the climate either has or has not changed during historical times ? (a) The influence of wars. — The depopulation caused b)^ wars is one of the best-known facts of histor}\ The question now before us is whether, other conditions remaining unchanged, frequent wars w//jY cause pennanent and progressive depopu- lation. Examples from many lands might be quoted, but Persia itself furnishes an answer. The province of Astrabad is one of the few in Persia which are blessed with an abundant rainfall and great natural advantages. For centuries its inhabitants have been exposed to the terrible raids of the fierce Turkomans and ha\'e also had the disadvantage of a x^xy unhealthful climate. Their condition as described by Vamber}- in the early sixties was most pitiable. Even as late as 1880, when conditions had much improved, owing to the proximity of Russia, O'Donovau (p. 190) relates that murderous affrays were frequent even in the immediate vicinity of Astrabad. Yet in almost the same paragraph the author enlarges on the density of the population, Persian villages of from 20 to 30 houses being scattered ever}- 500 or 600 }ards. The fertilit\- of the region is so great that the people persisted in coming into it, in spite of the fact that their numbers were frequently decimated by the Turkomans. Azerbaijan, the northwestern province of Persia, furnishes a more striking example of the same sort. This, according to Curzon (p. 514), "is the province which, excepting only Khorasan, has more often been violated by foreign invasion than any other part of Persia. ... Its fertility of resources entitle it to be called the granar\- of Northern Iran." Tabriz, the ca2)ital (p. 518) "has fallen the first victim to invading annies, and has been successively held by Arabs, Seljuks, Ottomans, Persians, and Russians. What the rage of conquest has spared, nature has interfered to destroy. The city has been desolated by frequent and calamitous earth- quakes. Twice we hear of its being leveled to the ground before, in 1392, it was sacked by Timur, whose path was strewn with mins that vied with the convulsions of nature. Five times during the last two centuries has it again been laid low. A reliable historian tells us that 80,000 persons perished in the earthquake of 1721, and we hear from another source that half that number were claimed for the death- roll by its successor in 1 780." Yet in spite of wars and calamities the fertilit)- of 3IO THE BASIN OF EASTERN PERSIA AND SISTAN. the province is such that the city of Tabriz (p. 521) now numbers a population of nearly 200,000 and is the connnercial metropolis of Persia, while the province (p. 517) contains 2,000,000 inhabitants, or from 25 to 40 per square mile, according to the estimate which is put upon its area. Ruins are found in many parts of Azerbaijan, but the}- do not give the impression of a countr)- whose population and resources have steadily declined, but rather of a countr}' which has suffered and recov- ered. If war and calamit}- are the chief causes of depopulation and the fall of nations, why has Tabriz lasted so steadily, and why is Azerbaijan so prosperous and populous ? A comparison of the four provinces of Khorasan, Azerbaijan, Kirman, and Sistan is suggestive. Khorasan (Curzon, pp. 180, 514) has suffered from war more severely than any other province of Persia. Its northern portion, where the rain- fall is greatest and where also the greatest amount of fighting has taken place, is to-day one of the most prosperous portions of Persia. It contains abundant niins, but they are by no means the impressive features which they are farther south. The southern and drier part of the province is full of niius and has suffered great depopulation. Azerbaijan, which (Curzon, p. 514) has suffered from war more than any province except Khorasan, is the most prosperous and thickly popu- lated part of Persia. The relative abundance of its water-supply renders its future hopeful. Sistan has suffered from wars, but less severely than the two preceding provinces. Nevertheless, it has been depopulated to a far greater extent. Its extreme aridity renders recovery well-nigh impossible, except along the Helmund. Kirman (Sykes, p. 60) lies so remote behind its barrier of deserts and mountains that it has suffered from war much less than an}' of the three preceding provinces. Yet its ruined cities and its appearance of hopeless depopulation are almost as great as in Sistan. If war and misgovemment are the cause of the depopulation of Persia, it is remarkable that the two provinces which have suffered most from war and not less from misgovemment should now be most prosperous and least depop- ulated ; while the two which suffered less from war and no more from misgovem- ment have been fearfully and, it would seem, irreparably depopulated. It is also significant that the regions which have suffered the greatest ruin are those where water is least abimdant and a decrease in the supply would most quickh- be felt. Wars and misgovemment do not seem to necessarily cause depopulation, nor has that process gone on most rapidly where war has been most pre\'alent. (d) The density of the population of Iran. — It is often asserted that with proper methods of irrigation Persia might support a much larger population, and the Persians are taken to task for not utilizing their resources. The Persians, as Hol- dich (p. 374) says of the Afghans, " have from time immemorial been great practical irrigation engineers. Ever>' acre of rich soil is made to yield its abundance by means of ever)' drop of water that can be extracted from overground or underground sources. It would be rash to say that the cultivable area of Afghanistan could be largely increased." Goldsmid, who knew Persia from end to end, was of the same opinion in regard to that coinitry, as he shows (r, p. 186) when he speaks of "the precari- ousness of cultivation (in Persia as a whole), even where to many travelers fertility has appeared undeniable and of considerable extent." CLIMATE AND HISTORY. 3 II The mistake of overestimating the possibilities of Persia is ven- common among travelers. For instance, O'Donovan (I, pp. 426-427) describes the country between Abasabad and Mazinan, a few miles west of Sabzawar, on the road from Meshed to Teheran, as "a dreary- flat, entirely uncultivated, though plentifully supplied with water from the Kal IMura River, which has left marks of extensive inundations in numerous white deposits of salt. This plain would undoubtedly produce abundant crops of rice if properly cultivated." After passing numerous ruins of fortifications, reservoirs, tanks, and other structures, " we crossed the Kal Mura, a river about 40 yards wide here and tolerably deep, though on the maps it is usually marked as dry in summer. The country around was once extensively cultivated, as the traces of the irrigating ditches show. . . . Nowadays, culti- vation is only attempted immediately around the towns, and even there . . . the crops are miserably poor." In June, 1880, when O'Donovan traversed this region, the Kal Mura River must have been phenomenally high, for when Smith (p. 376) passed this way in IMay, 1872, a year of ver}- fair rainfall, with unusually good crops, he foimd the Kal Mura at the same place " a narrow rivulet of salt water." Appar- ently it was lack of water, not lack of energy, which prevented the Persians from raising O'Donovan's " abundant crops of rice." Only a year previous to Smith's journey this ver^,- region suffered from a famine of such frightful severity that he found (p. 367ff.) skeletons of men along the road where they had died of hunger, skulls of children in the very houses, 450 out of 600 shops in Nishapur closed and the others barely able to subsist. Sebzewar (p. 373) was reduced from a population of 30,000 to scarcely 10,000. Ever,-where death ran riot and frequently half the people of a village perished. The famine extended with great severity over all Persia except the northwest, and is described by Goldsmid, Bellew, Smith, and St. John. For six years the rainfall was scanty and there was much suffering. Then came a season when the crops in many places failed almost entirely, and thousands of people perished in ever)- province. In view of the periodic return of such famines it does not seem probable that Persia is capable of supporting permanently a population greatly in excess of that of to-day. (c) Independent evidence as to the climate 0/ antiijitity. — Independent evidence as to the climate of antiquity is hard to find. It must be looked for chiefly in the fonns of historical or written record, archeological record, legend, and plusiographic record. The written accounts which afford evidence as to the ancient climate are scattered in numerous inaccessible volumes and have not been investigated. A few of the more prominent, such as Alexander's march and the statement of Istakhri that in the tenth centurj- the God-i-Zirrah was 100 miles long, have been mentioned. In general it is well known that ancient authors down to Mohannnedan times speak of Persia in a way which implies a much greater productiveness and beauty and a much more abundant growth of trees than at present, but their statements lack the quantitative element which is necessary- for a convincing solution of the question. Archeological evidence is more abundant and exact. The dams of Baluchistan, the ancient fort of Shah Duzd, the oasis of Merv, and the village of Bal Kuwi are cases where it seems as though there had been more water in earlier times. Probably a more complete study of Persian archeolog}- will go far toward sohing the problem. 312 THE BASIN OF EASTERN PERSIA AND SISTAN. LEGENDS. Legends are proverbially untrustworthy, but there is usually a solid kernel of truth in their center. Smith (p. 350) relates an ancient tradition common among the natives of Bajistan to the effect that the whole country around Bajistan was once covered by the sea, and that the place derives its name from two words signi- fying " to take toll," alluding to the toll at the ferry paid by travelers for boat- hire when the waters had jiartly receded. Farther east along the borders of the same playa which lies near Bajistan, " Yunsi (the Persian form of Jonah) is marked by local tradition as the spot on which the prophet Jonah was cast by the whale, and where he lay for many days concealed under a ptimpkin plant." Sykes (p. 93) mentions these traditions and adds : " Again, further east, on the Herat road, is the village of Langar, signifying an anchor, and so a port, and according to M. Khanikoff, there is an ancient tradition that Langar was a harbor on the great inland sea. Although legends are as a rule far from tnistworthy, yet in the two instances given it is hard to understand how they came to exist, unless there had been an inland sea at some not ver>' remote period." Smith (p. 367) relates another legend which does not fit quite so well. Ja-i-Gharak is a village 20 miles south of Meshed, on the direct road to Nishapur. It is located in a mountain valley, 1,200 feet above Meshed. The name means "place of drowning," and is derived from an old tradition that the country here was once covered by the sea, and that a ship foundered here. Although Smith mentions a small lake which has been artificially dammed below the village, it is hardly possible that a large lake could ever have exi.sted here, as it may possibly have done near Bajistan, Yunsi, and Langar. It may be that the name has been transferred a few miles across the mountains from tlie borders of the Dasht-i-Lut, which must have been a lake if the rainfall was ever greatly in excess of that of to-day. THE LEGENDARY HISTORY OF SISTAN. Sistan has its own crop of legends. The village of Deh Abbas Khan lies on the shore of the lake 2 or 3 miles east of Kuh-i-Khoja, and is inhabited by Sayids, who are suppo.sed to be one of the oldest and purest Persian stocks in existence. According to their own traditions, they have inhabited the country from time immemorial, and are the descendants of the ancient Zoroastrian population. The chief of the village possesses an ancient book which has been handed down to him from many generations of ancestors, and is now his dearest treasure. From this book he partly read, but mostly related to me the following traditions : Long, long ago alJ Sistan was occupied by water, a great lake, which covered not only the swamp and the site of the modern villages, but the site of Zahidan and .the other ruins as well. King Sulinian (Solomon) saw the lake and perceived that if it were free from water the bottom would be very good for grain and melons and all sorts of fruit. At that time there was no more rain than now, but the rivers, which came from springs in tlie mountains, were very much larger. Desiring to benefit mankind, King Suliman sent for his " dhus," huge giants, each with a single eye looking upward from the top of his head, and ordered them to reclaim the lake. Swifter than man can imagine they went to work, and digging up earth from this side and from that, carried it on their shoulders in bags, and filled the lake. By noon the work was completed, and hence the country is sometimes called " Nim-ruz," or " Half day." When the work was finished the " dhus " went to the springs in the mountains and covered them, so that the waiter no longer came out. Since that time there 'has been some water in the lake, but far less than formerly. CLIMATE AND HISTORY. 313 My ancestors, whose record is in this book, came to Sistan from Persia a thousand and forty- three years ago (A. D. 860). At that time all the villages were around Zafhidan, where the ruins now are. The site of this village, Deh Abbas Khan, was under water, arid only became habitable ninety years ago. It is now but very little above high -^vater level, and in the phenomenal flood of May, 1903, it was under water for a time. Later I visited the niins on the mesa of Kuh-i-Khoja with Mehemet Bey of Afzelabad, the "arbab" or chief of the antique race of Sayids, who told me the same story with less detail. He added a few points which are worth recording. In his bo)-hood, si.xty years ago, the water about Kuh-i-Khoja was more abundant than now, and came from the south from the Shila instead of from the north, as it does to-day. The ruins of Kuh-i-Khoja are those of structures built by a king called Kaha-Kaha, by whose name they are still called. They belong to the same period as the ruins of Sabari, which are built of burned brick and lie at the bottom of what is now the main northwest bay of the lake. At that time, before the building of Zahidan, there was no water in the lake of Sistan. As we approached the top of Kuh-i-Khoja the "arbab" stopped me and, pointing to two small holes in the rock beside the path, remarked, " There was a spring here once, but it was closed by the Holy Man, Hazret Mehemet Ali (one of the immediate successors of Mohammed). He stepped on the spring and caused it to drj' up. His heels made these holes." When I asked if there were other springs of the same sort, the "arbab" replied that he knew of another on the north side of Kuh-i-Khoja, a second at Bendan, called Sum-i-Duldul, and a third at Malik-Siah-Kuh, in the comer where Persia, Afghanistan, and Baluchistan meet. All three were closed in the same way by Hazret Mehemet Ali or by his horse. At Malik-Siah-Kuh, the "arbab" added, there was formerly a kanat or underground water channel, but now it is dry. From what has just been related it appears that the history of the lake of Sistan, as preserved in the traditions and written records of the ancient race of Sayids, consists of the following periods : (i) A time when water covered the area now occupied by the lake, the swamp, and the cultivated plain. (2) A time when the lake diminished in size and its shores were occupied b}- man. Meanwhile the size of the rivers decreased and springs dried up. At last the lake had so entirely disap- peared that the town of Sabari was built in one of the lowest parts of its bed, and Kaha-Kaha was built on what is now an island, but was then dr^• land. (3) Then the water returned to the lake, although the springs still continued to drj- up. The city of Zahidan was built. During the days of its prosperity the lake was larger than now, and probably received its water via the Shila. (4) Last comes the modem period, the last few centuries, during which the lake has shnnik to its present size and receives all its water-supph- via the delta of the Helnuind. AGREEMENT OF LEGEND, HISTORY, AND PHYSIOGRAPHY. The manner in which this traditional histor)- agrees with the historj' already inferred from physiographic e\-idence deserves careful attention. That inferred history may be recapitulated as follows : (i) During one of later fluvial epochs the upper or 25-foot beach was fonned and the lake probably covered the whole of the swamp and plain of Sistan and also the God-i-Zirrah. 314 THE BASTN OF EASTERN PERSIA AND SISTAN. (2) A decrease in the size of the lake ensued because of decreased rainfall or increased warmth. (3) Next, the lake stood at the level of the lower beach, with an area greatly diminished from that of the time of the upper beach. As this is the level at which the lake overflows permanently to the God-i-Zirrah, the water may have stood here twice. The last time was probably ver>- recent, because the bluffs left by it are so fresh that they can scarcely have existed more than a few hundred years. (4) From this tiiTie of relatively high water the lake appears to have shrunk gradually to its present condition, as is .shown by the transition from the lower of the old beaches to the present shoreline. Colonel McMahon believes that the condition of the reed-beds proves this decrease in size to be still in progress. The agreement between the traditional and the physiographic history of Sistan is so close as to amount almost to identity. If we assume that they are identical, and put them together, we find that they match a third set of facts, the historical, which have already been mentioned, and a reasonable sequence of events presents itself In this we begin with what was probably the last fluvial epoch, either when the lakes of Sistan and Zirrah were united and stood at the 25-foot beach, or more probably when the lake of Sistan stood for the first time at the 15-foot level and overflowed to Zirrah. As the fluvial epoch began to wane, springs dried up, the rivers decreased in volume, and the level of the lake fell. As the water retired the abandoned shores were occupied by human inhabitants, who we may suppose began to practice irrigation at an early date. At first the largest tract of irrigable land lav along the relatively elevated neck through which runs the Sliila. Accord- ingly the largest canals were dug in this direction. Thus it happened that the God- i-Zirrah, which was now separated from the Hanuni-i-Sistan, received the greater share of water. Indeed, it is probable that practically the whole stream of the Helmund flowed to Zirrah, for Smith (p. 285) says that in prehistoric ages the Helmund is reported to have flowed from the dam of Kamal, where it now turns north, in a southwest direction to the lake of Zirrah, and tradition has it that Khai Khusru sailed down it in a vessel. Sykes (p. 365) quotes Istakhri to the effect that in his day, the tenth century, the river flowed in the same way. Earlier classical writers speak of only one lake in this part of the world. It is probable that at this time Sistan was entirely drj', and the towns of Sabari, watered presumably by the Harud or Farah River, and of Kaha-Kaha, watered from the Shila, were built in what is now the lake. It is not to be supposed that the absence of water in the lake of Sistan indicates extreme aridity, for at this time not only was the lake of Zirrah a hundred miles long, according to Istakhri, but Sistan was in its glorj'. At the height of its prosperity a region which, as Curzon (I, p. 227) puts it, " contains more ruined cities and habitations than are perhaps to be found within a similar space of ground anywhere in the world," must have consumed an immense amount of water in the irrigation of its fields. To furnish this and at the same time fill the great lake of Zirrah, the rivers must have been larger than now. The limits of this period of prosperity and of abundant water-supply can not be stated, but they seem to have included Alexander, 300 b. c, and Istakhri, 900 a. d. CLIMATE AND HISTORY. 315 Again there was a change. The bed of the lake of Sistan was once more filled with water to a height greater than that wliich is now reached, but less than in the previous epoch of high water, for Zahidan was not covered as it had been before. Between the time of Istakhri and the present the Helmund was diverted from a southwestward to a northward course, and this was probabh- the cause of the increase in the size of the lake. This is the more probable because from historical and archeological evidence it is known that Zahidan was built soon after the time of Istakhri. To suppl)- so large a city with water a large amount must have been withdrawn from the Helmund before it reached the God-i-Zirrah and turned in tke direction of Sistan. For some centuries, until its destruction by Tiniur at the end of the fourteenth centur>', Zahidan continued to flourish. It is probable that the lake stood at a high level for a considerable portion of this time, for it was able to fonn, or at least to rejuvenate, a well-defined shoreline, with broad beaches and high bluffs. During the last five centuries, since the fall of Zahidan, there has been a gradual decrease in the size of the lake and in the density of the population that surrounds it. How this could take place without a dimunition in the water supply it is hard to understand. The historj- of Sistan, so far as it can be made out, seems to indicate a gradual desiccation of the countr}- from early historical times down even to the present. The evidence of archeology, historj', and tradition in the surrounding countries points in the same direction. At Sistan history and physiog- raphy appear to join hands, for the change from the conditions of greater water- supply during antiquity to the desiccation of to-day is apparently the change from the last fluvial epoch to the present interfluvial epoch. 3l6 THE BASIN OF EASTERN PERSIA AND SISTAN. BIBLIOGRAPHY. BellEw, H. W. From the Indus to the Tigris. Lon., 1874, pp. 496. An account of a journey from Quetta via Sistan to the Persian Gulf. An interesting and valu- able 'book, written in a scientific spirit. Blanford, W. T. (a) On the Nature and Probable Origin of the Superficial Deposits in the Valleys and Deserts of Central Persia. Quart. Journ. Geol. Soc., London, vol. 29, 1873, pp. 493-503. One of the most valuable contributions to Persian gec^raphy and geology. (6) Zoology and Geology. In "Eastern Persia," Vol. II, L., 1876, Geology, pp. 439-506. One of the most useful books on Eastern Persia. Chirol, Valentine. The Middle Eastern Question. Lon., 1903, pp. 500. From a political and literary standpoint this book ranks high. Scientifically it i« valuable for its vivid picture of the contrast between the Persia of the past and of the present. CuRZON, Geo. N. Persia and the Persian Question. Lon., 1892, 2 vols. This is generally agreed to be the best book on Persia as a whole. Unfortunately it deals very briefly with Eastern Persia. Davis, Wm. M. (a) Elementary Meteorology. Boston, 1894. (6) An Excursion to the Plateau Province of Utah and Arizona. Bulletin of the Museum of Comparative Zoology of Harvard University. Vol. XLII, 1903, pp. 1-50. (c) The Mountain Ranges of the Great Ba^in. Ibid., pp. 129-177. (d) River Terraces in New England. Ibid., Vol. XXXVIII, pp. 279-346. Ferrier, J. P. Caravan Journeys and Wanderings in Persia, Afghanistan, Turkestan, and Belu- chistan. Lon., 1857. A fascinating volume of exciting adventures and wonderful escapes. It contains interesting accounts of ithe manners and customs of the various people encountered, and brief notes on history and geography. Forbes, Frederick. Route from Tmrbat Haideri, in Khorasan, to the River Heri Rud, on the bor- ders of Sistan. Journ. Roy. Geog. Soc, vol. 14, 1844, pp. 145-192. A fairly interesting journal published almost as written. Although the work contains con- siderable information about villages, Turkoman raids, etc., it is chiefly of value to the traveler who proposes to follow the same route. GoLDSMiD, Sir Frederic. (a) Introduction to "Eastern Persia," Vol. I, pp. ix-lviii. A sketch of the history and politics of the eastern border of Persia from Sistan southward. (6) Journey from Bandar Abbas to Mash -had by Sistan, with some account of tilie last- named Province. Journ. Roy. Geog. Soc, vol. 43, 1873, pp. 65-83. A good account of a journey, with an excellent summary of the geography of Sistan. It con- tains, however, little which is not found in later works. (c) Notes on Recent Persian Travel. Journ. Roy. Geog. Soc, vol. 44, 1874, pp. 183-203. A readable account of a few general features of Persia, of a journey from Bushire to Tehe- ran, and of the ravages of the famine of 1871. HoLDiCH, T. H. The Indian Borderland. Lon., 1901, pp. 397. An account of the borders of Afghanistan from a surveyor's standpoint. Although the book is arranged according to the author's journeys, not by subjects or places, it is a valuable contribution to history and geography. It contains some excellent descriptions of scenery. Landor, a. H. S. Across Coveted Lands. 2 vols. N. Y., 1903. A well-written Ixxik, containing a large amount of information, part of which is unreliable. BIBLIOGRAPHY. 317 LOVETT, B. (a) Narrative of a Journey in Baluchistan. In "Eastern Persia," Vol. I, pp. iig-142. A concise, unadorned description of routes, of slight value e.xcept to the actual traveler. (6) Narrative of a Visit to the Kuh-i-Khwaja in Sistan. Joum. Roy. Geog. Soc, vol. 44, 1874, pp. 145-152. A personal account of a visit to the holy mesa of Sistan, and of the writer's attempts to carry on surveying operations. Malcolm, John. The His.tory of Persia. 2 vols. Lon., 1815. This book is still one of the most valuable sources of information on Persia. MacGrEcor, C. M. Wanderings in Baluchistan. Lon., 1882. Very brightly written and entertaining, although not containing much that is of perittanent value. Markham, Clements R. The Basin of the Helmund. Proc. Roy. Geog. Soc, n. s., Vol. I, p. 191. An empirical account of the mountains surrounding the Helmund basin, of the main tribu- taries of the river, and of the chief routes. McMahon, a. H. (a) The Southern Borders of Afghanistan. Geog. Journal, Apr., 1897. A short account of the people and physiography of the southern border of Afghanistan. Valuable and interesting, (t) The Baluchistan Desert, south of the Helmund River. Quart. Journ. Geol. Soc. of Lon., vol. S3, pp. 289-295. A brief account of the physical geography of the region similar to that contained in (a), followed by notes on various rock specimens. O'DoNOVAN, Edmond. The Merv Oasis. 2 vols. Lon., 1882. An interes.ting book, full of stirring adventures. Northern Persia is described chiefly from a political and historical standpoint, but there are also good accounts of the people and of physiographic features. Rawlinson, H. C. Notes on Sistan. Journ. Roy. Geog. Soc., vol. 43, 1873, pp. 272-294. A scholarly article containing a good summary of the history of Sistan and of the changes in its canals and water-supply. Smith, Euan. The Perso-Baluoh Frontier Mission, 1870, 1871, and the Perso-Afghan Mission, 1871, 1872. In "Eastern Persia," Vol. I, pp. 145-391. A straightforward, trustworthy narrative, with many valuable, though empirical, descriptions of isolated phenomena. St. John, O. B. On the Physical Geography of Persia, and Narative of a Journey through Baluch- istan and Southern Persia. In "Eastern Persia," Vol. I, pp. 1-115. The chapter on the physical geography of the country is of a general character, and is of great value. The remainder is an account of a journey, with occasional descriptions which are of permanent value. Sykes, P. M. Ten Thousand Miles in Persia, or Eight Years in Iran. Lon., 1902, pp. 481. This book is easily the most valuable work on Eastern Persia. It aims to supplement the work of Lord Curzon. Unfortunately the order of presentation is based strictly on the accidental circumstance of the writer's line of march, and a single subject is scattered in many places. The amount of research involved in the production of the book, and its accuracy, make it indispensable to every student of Persia. Vredenburo, E. a Geological Sketch of the Baluchistan Desert and Part of Eastern Persia. -Memoirs of the Geological Survey of India, Vol. XXXI, part 2, 1901, pp. 179-302. This -work embodies a large amount of valuable data, and is the only recent scientific work on this part of the world. Yate, C. E. Khurasan and Sistan. Lon., 1900, pp. 442. An exceedingly personal narrative of travel, with bits of historical, commercial, and military information scattered through it. I NDEX. PAGE. Abukumof Station, sketch of range near. . . 78 jllolian erosions 252 Afghan depression 237-242 Afghanistan 5,11 Afrosiab 11, 18 Aibughir Gulf 6 Ak-Busa-Ga 150 plain of 126 Akhal-Tekin oases 41 Ak Sai 190 Ak-si S, 18 Alabuga River 102 Alabuga Valley 94 Alai crest 155 Alai epoch 14S Alai Mountains 171,178 Block uplifts in 17 Alai Valley 127, 133-136, 146, 179 Artemonof, General 4 Aryan 7, 13 Asatians, Captain 64 Asia, Central 3, 16 Western 5 Askhabad 4, S, 7, 18 Atrek River 10 Ruins near 9 Alexander Range 75 Alexander the Great II, 303 Altitude, Aral, Caspian, and Black seas.... S American formations compared with Tur- kestan 166 Amu Darya 5 Amu Delta 39 Amu River 54 Anau 5, 18, 307 Kurgan at 7 Anau Gorge 255 Anau terraces 256 Andizhan 5, 7. 6s Andreef, Mr 64 Aqueous series of basin deposits 249 Aral 3,4,6 Altitude 5 Fluctuations of 6 Old water lines above 6 Aralo-Caspian Basin 13 seas 18 Quaternary deposits in the Kara-Kum ^"j Aralo-Caspian Sea and deposits 25 .Archeology, notes on 114 Bactra 5 PAGE. Bajistan 268 Bajistan Basin 244 Bakharden 42, 43 Baku 3 Old Caspian shoreline near 30 Quaternary Caspian shorelines near. ... 28 Ridge northeast of 31 Sketch map of district southwest of . . . . 29 Baikh 5 Balkhan Mountains, Caspian shoreline in. . 35 Bal Kuwi 307 Barkhan near Bakharden 44 Basin, Great — Aral, Caspian, and Black seas 5 Basins, water 12 Bendan 278 Berg 6 Bibi-Eibat, oil-wells of 31 Bibliography for Report of W. M. Davis. 118-119 Binalud Kuh 266 Biiialud Range and neighboring basins 237 Black Sea 3,14 Altitude of 5 Mounds near 7 South coast of 26 Blanford, quoted 249 Bogandovitch, Mr 4 Bokhara 4, 5 Bones in mounds 8 Bosporus 26 bird's-eye diagram of 26 effect of closing 5 Brovtzine, Serge 3, 23, 64 Buildings, submerged 7 Bural-bas-tau 73 Buuzan Range 49 Calcium sulphate, concretionary growths of. 141 Canals 10 abandoned 7 near Son Kul 115 Carnegie Institution of Washington 3 Carved stone on plain at east end of Issik Kul 116 Caspian region 24 shoreline in Balkhan Mountains. . . 35 shorelines, Quaternary, near Baku.. 28 Tertiary and Quaternary 24-25 Caspian Sea 3,^7, -4 Altitude of 5 Old shorelines above 16 Cassini, Count 4 Caucasus 14 319 320 INDEX. , rAGB. Central Turkestan, sketch map of i6o Chadir Kul 167, I74 Chahak Basin 243 Chalai Range 84 Chani Well 264 Charjui, sand dunes south of 57 Chau Bineh Basin 243 Cherkasof, Baron 4 Chernichcf, Director 64 China 5, 10 Choate, Hon. Joseph II 4 Chulak Range 62 Chu River 97 Relations to Issik Kul m Circles, stone 7 Cirques 90-9' of Trans-Alai Range 13S Climate in Tian Shan 7° of antiquity 311 of Persia 227 oscillations 17 Climatic changes, influence on Persia.... 253-271 Cobble deposits near Krasnovodsk 35 spit on a ridge near Zuyk 32 Darak kurgan 146 Dasht-i-Lut, northern border of 308 terraces on borders of 267 Davis, Wm. M 3, 4, 5. 7, 16, 17, 18 On a Journey Across Turkestan 23-119 Deformation and erosion, period of 93 de Morgan, M. J 7, iS Depopulation of Iran 308 Deposition and erosion in Persia 246 and uplift, long continuance of processes of 170 period of 92 Desert of Despair 232 Desert plains, aggrading rivers of 55 plains of Turkestan 54 proportion of 5 Desiccation 6 Progressive 6, 13. 16 Diversion theory 288 Dolmens 7 Dorandt 6 Drowned valleys 108, 144 Dsungarian Ala-tau, outline of 11 Dubosof, Mr 4 Dungsugot 211 Duruigar Valley, terraces of 52 Dushak 257 Earthquake at Kuchan 236 Eastern Persia, literature concerning 221 Outline of report upon 222 Physiography of 225 Quaternary climatic changes of 273-275 Elburg Mountains 17 Erosion, amount of 182 and deformation, period of 93 and deposition in Persia 246 of mountains 247 Escarpments of Alai Valley 135 Evaporation 6 Extinct lake of Zorabad 239 Fergana 7, 60, 123 Fergana Basin 181 Fergana lowland plains 17, 151 Firuza Basin 47 Fluvial or lacustral theory 290 Gedeonof , General 4, 64 Genghis Khan 12 Geography, physical 16 Geological history of Iran Basin 232 of Northeastern Persia. 233-245 Geological series 162 Ghiaur Kala 10, 18, 56 Glacial and lake level advances, fluctuations explained 143 epochs 16, 14s, 184, 186-198 erosion in higher ranges 89 geology of Kara Kul Basin 140 period in Asia, subdivision of 183 period, subdivision of 88 period, summary of 199 records in Tian Shan 84-92 Glaciation 182 of Asia compared with that of America and Europe 200 Glaciers 6, 16, 182 God-i-Zirrah 283 Golden Horn 26 Gorge of Western Kugart 99 Gravel deposits 250 Gravels of Sistan 291 Gruen wedel 14 Gulcha 149 Ilaji Hussein Beg Valley 267 Helmund, delta of 281 Helmund River 276 Heri Rud River 258 Hcri Rud Valley 237 Hilkof, Prince 4 Hindu Kush dam 257 Horsts, theory of 82 Hungary, mounds in 7 Huntington, Ellsworth 3. 4. 5, 16 On a Geologic and Physiographic Re- connaisance in Central Turkestan.. 159-216 On the Basin of Eastern Persia and Sistan 217-315 Ice-cap of Russia 17 Imperial Academy of Sciences 4 Imperial Geographical Society 4 India n, 14 Inscriptions, pictographic 7 Interglacial intervals 17 Iran, ancient climate of 302 depopulation of 308 Iran Basin 230,232 Irtysh River 79 Iskender Kala 10 Ispairan Valley 207 INDEX. 321 PAGE. Issik Kul 5, 7, 16, 18 Drowned Valley in plain at east end of. 108 Ranges near 74 Recent changes of 109 Rivers of 96 Shorelines of log Sketch map of ranges southwest of. ... 75 Issik Kul Basin 105 Issik Kul District 115 Itinerary of a Journey Across Turkestan. . 23-119 Ivanof, Governor-General and Madame.... 4 Jai Tebeh 210 Jam Basin 243 Jaxartes S Jebel, Quaternary shorelines near 33 Jizak 18, 59 Railroad cut south of 59 Jukuchak Pass 172 Jukuchak Valley, moraines of 186 Juvan-arik 96 Kach-kar 96 Kach-kar Basin 96 Kambar-Ali, the Min-Bashi of Kugart 65 Kanab Canyon 272 Kan Su Valley, moraines of 193 Kaplan Kul 208 Kara-bulak, loess drifts near 62 Kara Jilga moraine 142 Kara Kermak 167 Kara Kul 129, 130 Kara Kul Basin 138-142 Kara Kul Lake, high shorelines around.... 17 Kara Kul Lake and Syr Darya 121-155 Kara-kum, Quaternary Aralo-Caspian Z7 Karpinsky, Mr 4 Kashgar Basin 5, 175, 181 Katin- Art Pass 148, 155 Kauf mann. Mount 128 Kettle-hole lake 133 Khaf, playa of 264 Khoja Ishken 182 Khoja Ishken Valley, moraines of 187 Khokand 5 Khorasan 4 Khorasan Mountains 233 Kibitkas, Turkoman, village of 45 Kichik Alai 180 Kirghiz caravan 125 character of 66, 125 Kizil-Art 129 Kizil-Art Darya 146 Kizil-Art Valley 136 Kizil Kul, observation in region of 143 Kizil Kul Steppe 142 Kizil Su 146 Kogneh Nemeksar Lake 260 Kok Kiya 206 Kok Su Valley 187 Kok-tal Range 74 Komorof, General 7. S Konshin 39 FAGB. Kopet Dagh. 46-54, 233 Dislocation of mountains 17 Geological outline map of 46 Northern slope of 254 Terraces (dissected) at base of 42 Korolkof, Mr 64 Korytof, Colonel 64 Kotir Kul 143 Krasnovodsk 4 Quaternary shorelines near 33 Kuchan earthquake 236 Kugalinsk village 62 Kugart Pass gg Kugart terraces 97, 114 Kugart Valley (western), loess in the 63 Kuh-i-Khoja 285 Kukol-Yasnopolski, Colonel 4, 47 Kulberenj 265 Kungei Ala-tau 76 Moraines in 87 Kurgans 7 Kurumdi epoch 145 Kusak Valley 62 Kuve-Gen-Shagai-ef 67, 68 Kuzzil Kur 167 Kuzzil Oi Basin 176 Kuzzil Su 179 Kyzil Irmak (Halys River) 27 Lacustral of fluvial theory 290 Lacustrine bluffs near Seh-Kuheh 296 Lake deposits versus playa deposits 286 Lake level and glacial advances, fluctuations explained 143 Lakes of Turkestan 208 Langar 152 Lenkoran country 18 Limestone in the Sugun Valley, folds in. ... 163 Literature relating to Eastern Persia and Sistan 316-317 Loess 18, 178 deposits of Turkestan 58 drifts near Kara-bulak 62 in Fergana 60 in Semiryetshensk 61 in (western) Kugart Valley 63 near Jizak 59 near Samarkand 58 plain II Lutuck 29s McCormick, Mr 4 Manytsch divide 18 Marghilan 5 Markou, Mount 47 Mature basins 248 Mealing stones in mounds 8, 9 Meanders and terraces 204 Medinsky, General 4 Mediterranean, Asian 3 .Merv, Ancient 'O Old 4.18 accumulation of ruins at 9 322 INDEX. PAGE. Men- Oasis 307 Old and Modern 55 Meslicd Basin 235 Mesozoic-Tertiary scries 163 Metallurgy 16 Metate method 8 Mil-i-Kasiniabad, ruins at 229 Min-Bashi of Kugart and his men 66 Min Yol Basin I77 Mohammedan cemeteries 11 Moraines in Kizil-Art Pass i37 in the Alai Valley 133-136 in the Kungei Ala-Tau 87 in the Terskci Ala-Tau 86 near Son Kul 84 Mosques at Samarkand 12 Mounds 7 in Hungary 7 in Southern Russia 7 in Southern Siberia 7 near Black Sea 7 on Kugart Terrace 114 Mudirum Basin, moraines of 19° Mudirum Su ^73 Murg-al) River 54,257 Muschketof '7 Nalifkin, General and Madame 4 Namali, synclinal valley southeast of 51 Narin Basin, terraces of 102 Narin formation 18 Narin Tertiary Basin 92-95 Neh, ruins of 3o6 Nemeksar Basin 243 Nemeksar, or the Playa of Khaf 264 North America, terraces in 272 Northeastern Persia, geological history of. 233-245 Norton, Richard 4 Oases o of Akhal-Tekin 41 Omsk 5 Osh 4, 5 Outlet theory 288 Oxus 7, 8 Paikent 5. 18 Ruins of 10 Paleozoic series 160 Pamir 4, 5, 138-145 Map of 124 Paropamisus 237 Penck, Professor 58 Persia 4. u, '5 as an example of the influence of changes of climate 253-271 as a typical example of an arid country 246-253 mounds in Northern -. 7 Physiographic Observations between the Syr Darya and Lake Kara Kul, on the Pamir, in 1903 121-155 Piedmont plains of Southern Turkestan. ... 40 slopes and valleys 106 PAOE. Pierce, Herbert 4 Plains of Southern Turkestan 36 Plehve, Mr 4 Polovtzof, Mr 64 Poslovsky, General 4 Pottery in mounds 8 PouIovtsoflF, Colonel 4 Przhevalsk, or Kara Kul 159 Pul-i-Khatun, salt lake of 263 Pumpclly, R. W 3, 17 Pumpclly, Raphael, on Physiographic Ob- servations between the Syr Darya and Lake Kara Kul 121-155 Quaternary Aralo-Caspian deposits in the Kara-Kum 37 Caspian shorelines near Baku. . 28 climatic changes of Eastern Persia 273-275 era in Sistan 285-302 history 13 period 182-214 shorelines near Krasnovodsk and Jebel 33 time 3 uplift 169-181 Quintus Curtius 12 Radloff, General 15 Railroad cut south of Jizak 59 Rhythmic warping theory 289 Richthofcn (von), Baron 4 Ridlcr, Mr 4 Ripplc-marks 164 Rivers, aggrading, desert plains of 55 Ruins, desiccation of ancient 305 of Old Kuchan 236 towns and "forts" 7 Russia, mounds in Southern 7 Sabazkim beach and bluffs 297 St. Petersburg 3. 4, 5 Salt Lake of Pul-i-Khatun 263 Samarkand 4> 5. '8, 58 Mosques at 12 Ruins lo-ll Samsun 26, 27 Sand-dunes near Seh-Kuheh 296 south of Charj ui 57 Sandhills near Bakharden 43 Sands, invasion of Sankar Valley 60 Sari Tash Valley I47. 148 Sazanovka 7" Schcil IS Schmidt, Professor 4 Schultz 6 Schwartz ; 5 Sediments of the great Kara Kul Basin 138 Seh-Kuheh beach and bluffs 29S Selsuparali Basin 5° Semenof, Mr 4 Semipalatinsk 7° Semiryetshensk 61 INDEX. 323 PAGE. Semiryetshensk and Semipalatinsk, ranges and steppes of 'J^ Serakhs 257 Serani Valley and village 48, 49 Seven-river district 61 Shila 283 Shorelines, Caspian, in Balkhan Mountains. 35 east of Trebizonde 27 of Issik Kul 109 of great Kara Kul Basin 138 Quaternary, near Jebel 33 Quaternary, near Krasnovodsk and Jebel 2,7> Shor Kul 208,263 Siberia 15 Mounds in Southern 7 Sistan 276-284 Causes of the alternations of 288 Gravels of 291 Legendary history of 312 Terraces of 293 Sistan and Basin of Eastern Persia 217-315 Sistan Lake, deposits of 285 Snowfield below Sutto-bulak Pass 88 Son Kul, moraines near 84 old canals near 1 15 stone circles near 114 Son Kul Basin 74 Son Kul Lake 7, 16 Southern Turkestan, plains of 36 Stein 14 StrobI, Dr 58 Stubendorf, General 4 Sugun Karaul 170 Sugun Valley, folds in limestone in 163 Susa 14 Excavations at IS Sutto-bulak Pass, snowfield below 88 Syr Darya 5, 7, i7. '55 Shrinking of 6 Syr Darya and Lake Kara Kul, Physiographic observations 121-155 Taka Valley, moraines of 196 Takka Pass 124 Taldic 5, 126 Taldic darya 148 Taldic Pass 148 Taldic Valley 148-151 Tamerlane 12 Tarentass T] Tashkent 4,5 Tate, G. P 229 Tchernachcf 4 Tejen River 54, 55. 258 Terek 5 Terrace development, scheme of 53 Terraces 201 among mountains from Meshed to Birjand 266 as a result of climatic changes. . . . 206 as a result of warping 203 PAGB. Terraces at Namali 51 (dissected) at base of Kopet Dagh. 42 examples of 254 formation, theories of 254 in North America 272 in Serani Valley 49 in Turkey 271 Kugart p7 of Duruigar Valley 52 of Narin Basin 102 of Sistan 293 of Western Kugart 98 on borders of Dasht-I-Lut 267 origin of 103 Terskei Ala-Tau, moraines in 86 Tertiary history of basins of Eastern Persia 242-245 peneplain 167 Tian Shan, climate in 70 glacial records in 84-92 origin of existing ranges 80 ranges, bearing on theory of horsts 82 rivers and valleys of 95 vegetation in the 70 weather in the 70 Tian Shan Mountains 6, 14, 16, 64-83 Development 72 Tian Shan Plateau 171 Tillo 6 Timur's Gate 59 Town sites 18 Towns, ancient 9 Trans- Alai, glacial epochs in 17 Trans-Caspian railway 4 Trans-Caspian region 3 Trebizonde 27 elevated shorelines east of 2^ gravels near 28 Tuluk Valley 96 Tumulus, growth of 8 Tumuli 7^18 Turanians 7^ j^ Turkestan, A Journey Across, by W. M. Davis 23-119 Turkestan 3, 4, IS, i8 Chinese 15 Russian 13, 14 Turkestan formations compared with Amer- ican 166 Turkey, terraces in 271 Turkoman kibitkas, village of 45 Ula-khol delta 106 Ulianin, General ^ Ulu-tuz gorge 93 Ungus 38,39 Uplands across the Bosporus, sketch of . . . . 26 Uplift and deposition, long continuance of processes of 170 Urgas-Khan 6S Urta-takoe 96 Usboi Channel 38 324 INDEX. TAOE. PAGE. Ussakovsky, General 4, 47, 220 Vate, C. E 284 Vegetation in the Tian Shan 70 Yermolof, Mr 4 Volga 5 Yeshil Irmak (Iris River) 27 Volkovnikof, Colonel and Madame 4 Yonof, General 70 von Richthofen, Baron 4 Zaitza, Colonel 4, 5 Wars, influence on depopulation 309 Zend Avesta 10 Weather in the Tian Shan 70 Zerafshan glacier 132 Windmills at Tabas 228 Zerafshan River 10 Yak Tash Basin 173 Zittel, Professor 8 Moraines of 192 Zorabad Basin 242 Yanchevetzki, V. G 4, 220 Zorabad, extinct lake at 239 11 Date Due 1VIAR16 1! I62 JUN ' I AUG 2 19 -H 4992U ises- /L<->, , 51 OCT 2 2 19115- FEB 4 1< I66 AjiG-n^y^ (lu » t n d n t QuartM r,^ 2 It TS w>«' Qa>a Q TR . IJOAN 0CtC6'89 / ' "^^ S^ •ai -^ -cjs g, z^--?. PRINTED UNIVERSITY of CAUFORHlA AT U)S ANGELES IJBRAjRY The Um D. RKED LWUB? UNITERHrrv of CAUKOKNU