i DEPARTMENT OF COMMERCE U. S. COAST AND GEODETIC SURVEY O. H. TITTMANN SUPERINTENDENT HYPSOMETRY PRECISE LEVELING FROM BRIGHAM, UTAH, TO SAN FRANCISCO, CALIFORNIA BY -WILLIAM BOWIE Inspector of Geodetic Work, and Chief of the Computing Division IT. S. Coast and. Geodetic Survey SPECIAL PUBLICATION No. 22 WASHINGTON GOVERNMENT PRINTING OFPICK 1914 (?»**— r e> tt o> e^ocJeTTi*. ^ou-v-cw, DEPARTMENT OF COMMERCE U. S. COAST AND GEODETIC SURVEY O. H. TITTMANN SUPERINTENDENT HYPSOMETRY PRECISE LEVELING FROM BRIGHAM, UTAH, TO SAN FRANCISCO, CALIFORNIA BY WILLIAM BOWIE Inspector of G-eodetic Work, and Chief of the Computing Division TJ. S. Coast and Geodetic Survey SPECIAL PUBLICATION No. 22 WASHINGTON GOVERNMENT PRINTING OPFIOE 1914 ADDITIONAL COPIES OF THIS PUBLICATION MAY BE PROCURED FROM THE SUPERINTENDENT OF DOCUMENTS GOVERNMENT PRINTING OFFICE WASHINGTON, D. C. AT 15 CENTS PER COPY ft Ubwy CONTENTS. rum General statement 5 Standard elevations 5 Orthometric correction 6 Theoretically best elevations 6 Dynamic numbers '. 6 Mean sea level at San Francisco, Cal 6 Detailed statement of results 7 Brigham, Utah, to Beowawe, Nev 7 Beowawe to Marmol, Nev 13 San Francisco, Cal. , to Marmol, Nev 19 Rate of progress 26 Cost of leveling 26 Organization of party 26 Connections with other leveling 27 Agreement of elevations at Brigham, Utah 27 Circuit closures 27 Probable and systematic errors 27 Instrument* used 28 General instructions for precise leveling 29 Study of errors 32 Investigation of systematic errors 33 Relations between the discrepancy and the times of running 34 Relation between errors of leveling and clear and cloudy sky 37 Relation between the errors of leveling and the forward and backward runnings of a line 42 Conclusions 43 Standard elevations 45 Elevations of permanent bench marks 45 Elevations of top of rail in front of railroad stations. 47 Descriptions of bench marks 48 General notes describing different forms and markings of bench marks 48 Descriptions: Brigham, Utah, to Beowawe, Nev 48 Beowawe to Marmol, Nev 53 Marmol, Nev. , to San Francisco, Cal 56 ILLUSTRATIONS. . I No. 1. Index map showing general location of the leveling 61 No. 2. Location of bench marks between San Francisco and Clippergap, Cal 62 No. 3. Location of bench marks between Clippergap, Cal., and Doden, Nev 63 No. 4. Location of bench marks between Doden and Fenelon, Nev 64 No. 5. Location of bench marks between Fenelon, Nev. , and Brigham, Utah 65 PRECISE LEVELING FROM BRIGHAM, UTAH, TO SAN FRANCISCO, CAL. By William Bowie, Inspector of Geodetic Work and Chief of the Computing Division, United States Coast and Geodetic Survey. GENERAL STATEMENT. This publication gives the results of a line of precise levels run along the Southern Pacific Railway from Brigham, Utah, to San Francisco, Cal., during the seasons of 1911 and 1912 by a party of this Survey under the charge of Assistant John H. Peters. The fine is 891 miles (1434 kilometers) in length and fixes the elevations of 315 bench marks. Several noteworthy features of this fine are: (1) That all of the work was done by one observer. So far as the writer is aware, this is the longest continuous line of levels in the United States ever run by one person. (2) For the first time a motor-driven velocipede car was used by a precise-leveling party of the United States Coast and Geodetic Survey. (3) The excellent progress made by Mr. Peters on his first season's leveling; he had done no precise leveling previous to 1911. This is especially remarkable, as the country traversed is thinly populated and villages at which the party could live were far apart. The engineer who wishes only to obtain the standard elevations of the bench marks and their descriptions may find the desired data on pages 45 to 60. At the back of this volume there is given an index which enables one to find easily the pages on which are the elevations and descriptions of marks at any particular place. Several members of the field and office force assisted in the computation of the fine of levels and in the preparation of this report. Especial credit is due H. G. Avers, who had direct charge of the computations and prepared the descriptions of the bench marks for publication, and J. H. Peters who assisted in the study of errors. STANDARD ELEVATIONS. There have been four general adjustments of the precise levels of the United States, each succeeding one having been made necessary by important additions to the net. The last adjustment showed the net to be sufficiently strong to serve without change (except for dis- turbed local areas) for giving fixed or standard elevations to the public. To this net, as fixed by the 1912 adjustment (the results of which are shown in Special Publication No. 18, of the Coast and Geodetic Survey), will be adjusted the separate lines as they may be run in the future. The fine under discussion, from Brigham, Utah, to San Francisco, Cal., has been fitted in or adjusted to the elevation of a bench mark at Brigham, with which it was connected, as given by the last general adjustment, and the elevations of certain bench marks in San Fran- cisco which had been determined by a connection with tidal bench marks at the Presidio by the city engineering department. The elevations given on pages 45 to 47 of this publication are considered as standard or fixed. From time to time in the future, general adjustments of the level net will no doubt be made in order to obtain the theoretically best elevations of the junction points, but such adjustments will not disturb the standard elevations, unless they are found to be greatly in error on account of blunders in the leveling or due to the rising or settling of the bench marks from earthquake disturbances or the operations of man. Occasionally the elevations of bench marks are changed by mining operations, drainage, and other local agencies. 5 6 U. S. COAST AND GEODETIC SURVEY SPECIAL PUBLICATION NO. 22. ORTHOMETRIC CORRECTION. 1 The orthometric correction was applied to the observed differences in elevation shown on pages 8 to 25 before they were adjusted between the San Francisco and Brigham elevations. This correction eliminates from the observed results the effect of the convergence of level surfaces as the poles of the earth are approached, and the elevations obtained represent the vertical distances of the points above mean sea level. On the line San Francisco to Brigham the total orthometric correction is —0.3122 meters. THEORETICALLY BEST ELEVATIONS. Every new line added to the precise level net will have some influence on the elevation of nearly every bench mark in the net, though in most cases this influence will probably be so small as to be negligible. Therefore for surveying and engineering purposes it is desirable that the elevations of bench marks be held fixed rather than be continually changed by very small amounts as new data are added to the net. But it is sometimes desirable to know the theoreti- cally best orthometric elevation of a bench mark. This can be obtained for a bench mark on the line between Brigham, Utah, and San Francisco, Cal., by applying to the standard elevation of the bench mark in question a correction which bears the same proportion to the difference between the theoretically best orthometric elevation and the standard elevation of bench mark "R" at Brigham as the distance between Brigham and the bench mark bears to the whole distance between Brigham and San Francisco. The theoretically best orthometric elevation of bench mark "R" at Brigham as obtained by the methods described on pages 57 and 58 of Special Publication No. 18 is 1309.1510 meters. DYNAMIC NUMBERS. 1 When the orthometric correction has been applied to the observed elevation of two bench marks which are in the same level surface, the surface of the water at rest in an elevated north-and-south canal, for instance, the two marks will have different elevations above sea level. This difference is so slight in practically all cases in which engineers are interested that it may be ignored. There are occasions, however, when it is desired to know the exact dis- tance in terms of some unit between the level surfaces in which two bench marks are situated. The difference between the two orthometric elevations will not give this information. In such cases the dynamic number of each bench mark must be computed, then the distance between the surfaces may be obtained in terms of the work done in raising a unit mass through a unit distance. If the stations should be in the same level surface then the difference between their dynamic numbers will be zero. As stated above, the orthometric elevations of two points in the same level surface will differ by the amount by which the surface containing them converges toward the sea-level surface in going from the more southern point to the other one. The convergence is a function only of the difference in latitude and the average elevation of the points. MEAN SEA LEVEL AT SAN FRANCISCO, CAL. The elevations of the bench marks established by the city of San Francisco, upon which the elevations of the line under discussion depend, are based upon a preliminary elevation of 8.970 feet above mean sea level for bench mark No. 15. Bench mark No. 15, also known as "Granite B. M.," is the reference bench mark for the tidal station at the Presidio. It is the top of the rounded head of a copper bolt set in the top of a granite post, 12 inches square in cross section and 36 inches long, imbedded in concrete on the east side of the road leading from the Presidio wharf to the Barracks and about 255 1 The orthometric correction and also dynamic numbers are discussed on pp. 49 to 53 of Special Publication No. 18 of the Coast and Geodetic Survey; also at length by Charles Lallemand on pp. 358 to 387 of his " Nivellement de Haute Precision" in the Encyclopedic des Travaux Publics; Paris et Liege, 1912. PRECISE LEVELING, BRIGHAM TO SAN FRANCISCO. 7 feet from the shore end of the wharf. The top of the stone is marked "U. S. C. S., 1897, B. M." The bench mark was established in August, 1897, and subsequently covered by the edge of the macadamizing of the road to the Quartermaster's warehouse. The tide staff at the Presidio was established in 1897. Since then continuous tidal obser- vations have been in progress. The following table gives the value of mean sea level above the zero of the tide staff of 1897, for each calendar year since its establishment. Year. Height. Year. Height. Year. Height. Year. Height. Feet. Feet. Feet. Feet. 1898 8.30 1902 8.57 1906 8.58 1910 8.42 1899 8.44 1903 8.53 1907 8.66 1911 8.61 1900 8.50 1904 8.83 1908 8.43 1912 8.49 1901 8.46 1905 8.65 1909 8.53 1913 8.51 Mean sea level for 16 years (1898 to 1913) =8.519 feet on the staff. The above readings have been reduced to the staff of 1897 on the assumption that bench mark No. 15 remained unchanged during the entire period of observations. The elevation of bench mark No. 15 above the zero of the tide staff of 1897 was accepted as 17.493 feet, which is the mean of 8 sets of levels taken at various times between the years 1897 and 1905. The elevation of bench mark No. 15 above mean sea level from the tidal observations 1898 to 1913 is therefore 17.493-8.519 = 8.974 feet. The difference between this value and the one (8.970) used in the computation of the elevations of the precise leveling bench marks is only 0.004 feet (1.2 millimeters) and is so small that the elevations have not been corrected to accord with the latest value of mean sea level. DETAILED STATEMENT OF RESULTS. BRIGHAM, UTAH, TO BEOWAWE, NEV. This section was run between June 26, and November 8, 1911. Precise level No. 7 and rods CC and DD were used for the entire line. The lengths of these rods at 0°C, as determined by the instrument division of this Survey, are as follows: June 8, 1911, rod CC, 3.0013 meters, rod DD, 3.0015 meters; January 12, 1912, rod CC, 3.0008 meters, rod DD, 3.0012 meters. These measurements show a slight shortening of the rods. The field measurements give no indication of a sudden change during the period of leveling. In the computation the mean length of the rods at 0.0° C. for the season, 3.0012 meters, or an excess of 0.40 millimeter per meter was used. The index correction of rod CC was —0.3 millimeter; of rod DD, —0.2 millimeter. Three bench marks, Q, R, and T, on the lino of levels between Ogden, Utah, and Poca- tello, Idaho, were recovered. The new determination of the differences of elevations between these three bench marks showed that R and T had maintained the relative position in which they were established, while Q had settled about 26 millimeters. The elevation of bench mark Q, published on page 132 of Special Publication No. 18, should therefore be used with caution for engineering and survey purposes. The elevations in the following table are based on an assumed elevation of 1308.9203 meters for bench mark R at Brigham, Utah. U. S. COAST AND GEODETIC SUBVEY SPECIAL PUBLICATION NO. 22. Results of leveling, Brigham, Utah, to Beowawe, Nev. Date. 1911. June 29 July 1-June 29. July 1-June 28. June 28-28 Do June 28-27 June 27-27 Do Do , Do June 28-27 June 26-26 Do Do July 1-1 July 3-8 July8-8 July 3-3 Do Do Do Do July 3-5 July 5-5 Do Do July 7-7 Do Do July 6-7 July 6-6 Do Do Do July 1-1 Do July 11-11 Do Do July 12-12 July 11-11 July 11-12 July 12-12 Do Do July 12-13 July 13-13 Do Do Do July 13-14 July 17-17 July 14-14 Do Do July 17-17 July 14-17 July 17-17 July 17-18 July 18-18 Do Do Do July 18-24 July 24-24 Do Do Do Do July 25-25 Do Do Do Do Do Do July 26-25 July 26-26 Do Do Do July 27-27 July 27-28 July 27-27 Do Do From B. M. to B. M. Dis- tance in kilo- me- ters. Q-10 10-9 9-8 8-7 7-6 6-5 5-4 4-3 3-2 2-J, 2-J 8 1-K» R-ll 11-12 11-12 12-13 13-14 14-15 15-16 16-17 17-18 18-19 19-20 20-21 21-Lj Lg-22- 22-23 23-24 24-25 25-26 26-27 27-T 28-29 29-M 9 M»-30 30-31 30-31 31-32 32-N, N(r-33 33-34 34-0 9 Og-35 35-36 36-P 9 Ps-37 37-38 38-39 38-39 39-Q, Q»-40 40-41 40-41 41-42 42-R 9 Rs-43 43-44 44-Ss S»-45 45-46 46^7 46-47 47-T, T„-48 48-U 9 U.-49 U.-49 49-V 9 Vk-50 50-W 9 Wj-51 51-52 52-53 53-54 54-X 9 Xr-55 55-56 55-57 56-57 57-58 68-59 59-60 60-61 1.568 1.375 0.987 0.964 1.227 0.983 0.986 0.977 1.170 1.128 1.128 Difference of elevation. Forward line. o.ias 0.614 7H^ 1.075 1. ail 1.311 1.192 1.271 1.263 1.102 1.269 0.986 1.291 1.210 2.014 0.254 1.207 1.420 1.293 1.273 1.272 1.151 1.161 1.095 1.211 1.134 1.096 1.041 1.041 0.789 1.007 1.116 1.022 1.244 1.023 1.320 1.376 1.197 1.137 1.467 1.467 1.559 1.351 1.356 1.356 1.161 0.613 1.115 1.385 1.325 1.285 1.582 1.132 1.132 0.682 0.824 1.205 1.648 1.648 0.993 0.461 0.857 0.557 1.097 1.017 1.057 1.121 1.090 0.747 1.028 1.028 0.985 1.071 1.059 1.020 m. - 3.7553 - 3.7529 - 4.1826 + 2.3468 + 3.0333 - 1.5243 - 1.6416 - 1.4722 + 4.1190 + 8.57*9 + 7.6399 + 7.6374 + 1'J. 1368 + 20.3041 - 4.2481 - 7.7889 - 9.2179 - 5.3208 - 0.4404 + 0.4679 + 0.5403 + 0.8441 + 1.5476 + 3. 1569 + 4.5292 + 1.1856 + 2.4001 + 4.0557 + 1.7453 + 3.3513 + 0.3498 + 2.4588 + 2.8321 + 1.7431 -10.9668 - 2.7640 - 0.0789 + 0.9181 - 0.5942 - 0.5920 - 0.3135 + 1.4582 + 1.3355 + 0.3801 - 0.3078 + 1.4855 + 1.5162 + 0.1301 + 0.8488 - 0.5364 - 2.2275 - 2.2241 + 2.6350 - 5.3485 - 0.3329 - 0.3335 - 0.0479 + 1.2777 - 1.8929 + 0.3152 + 2.5690 + 2.3873 + 3.3836 - 1.2972 - 1.2956 + 0.3097 + 0.9584 + 4.8963 + 9.9556 + 9.9549 +12.5909 + 4.9811 + 4.6148 - 1.9222 +13.2035 + 14.8016 +15.4260 +16.5604 +16.3466 +16.3425 +12.7663 + 17.2740 + 17.2797 + 14.6043 +15.0254 +15.4858 - 1.5021 Back- ward line. m. + 3.7497 + 3.7515 + 4.1866 - 2.3491 - 3.0329 + 1.5274 + 1.6427 + 1.4722 - 4.1166 - 8.5728 - 7.6337 - 7.6344 Mean. }" 3.7524 4. 1846 + 2.3480 + 3.0331 - 1.5258 - 1.6422 - 1.4722 + 4.1178 + 8.5738 + 7.6363 19. U-0 20. 3939 2485 + 4 + 7.7882 + 9.2223 + 9.2216 + 5.3239 + 0. 4382 - 0. 4681 - 0. 5414 - 0.8466 - 1.5482 - 3. 1564 - 4 5298 - 1.1825 - 2.3993 - 4.0542 - 1.7454 - 3.3538 - 0.3495 - 2.4619 - 2.8281 - 1.7435 1 ■ ■ . + 2.7646 + 0.0793 - 0.9174 + 0.5899 + 0.5957 + 0.3155 - 1.4591 - 1.3335 - 0.3827 + 3109 - 1.4848 - 1.5181 - 0.1284 - 0.8514 + 0.5363 + 2.2220 + 2.2263 - 2.6371 + 5.3466 + 0.3272 + 0.3315 + 0.0454 - 1.2780 + 1.8957 - 0.3139 - 2.5734 - 2.3845 - 3.3854 + 1.2901 + 1.2968 - 0.8088 - 0.9582 - 4.8924 - 9.9484 - 9.9590 -12.5922 - 4.9821 - 4.6155 + 1.9213 -13.2025 -14.8007 -15.4274 -16.5593 -16.3393 -16.3451 -12. 7646 -17.2780 -17.2803 -14.6047 -15.0264 -15.4857 + 1.5012 + 19.1369 +20.3940 Discrepancy. Par- tial. +3.5 -4.0 +2.3 -0.4 -3.1 -1.1 0.0 -2.4 -2.1 -4.6 +0.2 -0.2 - 4.2484 - 7.7886 - 9.2200 - 5.3224 - 0.4393 + 0. 4680 + 0.5408 + 0.8454 + 1.5479 + 3.1566 + 4.5295 + 1.1840 + 2.3997 + 4.0550 + 1.7454 + 3.3526 + 0.3496 + 2.4604 + 2.8301 + 1. 7433 -10.9675 - 2.7643 - 0.0791 + 0.9178 - 0.5930 - 0.3145 + 1.4586 + 1.3345 + 0.3814 - 0.3094 + 1.4852 + 1.5172 + 0.1292 + 0.8501 - 0.5364 - 2.2250 + 2.6360 - 5.3476 - 0.3313 - 0.0466 + 1.2778 - 1.8943 + 0.3146 + 2.5712 + 2.3859 + 3.3845 - 1.2950 + 0.3098 + 0.9583 + 4.8944 + 9.9544 +12.5918 + 4.9816 + 4.6152 - 1.9218 +13.2030 +14.8012 +15.4267 + 16.5598 +16.3434 +12. 7654 +17.2780 +14.6045 +15.0259 +15.4858 - 1.5016 ^TT Total accu- mu- lated. +12.0 + 15.5 + 11.5 + 13.8 +13.4 +10.3 + 9.2 + 9.2 + 6.8 + 4.7 I 4.9 + 4.7 + 0TT +0.7 +0.7 -4.1 -3.1 +2.2 +0.2 +1.1 + 2.5 +0.6 -0.5 +0.6 -3.1 -0.8 -1.5 +0.1 +2.5 -0.3 +3.1 -4.0 +0.4 -0.6 -0.4 -0.7 +0.3 -2.0 +0.9 -2.0 +2.6 -3.1 -0.7 +1.9 -1.7 +2.6 +0.1 + 1.6 +2.1 +1.9 +3.8 +2.5 +0.3 -2.8 -1.3 +4.4 -2.8 +1.8 +2.8 +0.1 -0.2 -3.9 -1.5 +1.3 + 1.0 +0.7 +0.9 -1.0 -0.9 + 1.4 -1.1 -2.4 -1.7 +2.4 +0.4 +1.0 -0.1 +0.9 -3.4 -6.5 - 4.3 - 4.1 - 3.0 -0.5 + 0.1 - 0.4 + 0.2 - 2.9 - 3.7 -5.2 - 5.1 - 2.6 - 2.9 + 0.2 -3.8 -3.4 -0.9 -1.5 - 1.9 -2.6 - 2.3 -4.3 -3.4 - 5.4 -2.8 -5.9 - 6.6 - 4.7 -6.4 -3.8 -3.7 - 2.1 Designation ofB.M. 0.0 + 1.9 + 5.7 + 8.2 + 8.5 + 5.7 + 4.4 + 8.8 + 6.0 + 7.8 + 10.6 + 10.7 +10.5 + 6.6 +5.1 + 6.4 + 7.4 + 8.1 + 9.0 + 8.0 + 7.1 + 8.5 + 7.4 + 5.0 + 3.3 + 5.7 + 6.1 + 7.1 + 7.0 + 7.9 1 Distance from B. M. R. 29 M» 30 31 32 N„ 33 34 9 35 36 P. 37 38 39 Q> 40 T 9 48 U, 49 V, 50 W> 51 52 53 54 X 9 55 56 57 58 59 60 61 km. 12. 115 10.547 9.172 8.185 7.221 5.994 5.011 4.025 3.048 1.878 1.075 Observed elevation above mean sea level. 2.386 3.578 4.849 6.112 7.214 8.483 9. 469 10.760 11.970 13.984 14.238 15. 445 16.865 18. 158 19.431 20.703 21.854 23.015 "2-T7IT 3.381 4.515 5.611 6.652 7.441 8.448 9.564 10.586 11.830 12.853 14.173 15. 549 16. 746 17.883 19.350 20.909 22.260 23.616 24. 777 25.390 26. 505 27.890 29.215 30.500 32. 082 33.214 33.896 34.720 35.925 37.573 38.566 39.027 39.884 40.441 41.538 42. 555 43. 612 44.733 45.823 46.570 47.598 48.583 49.654 50.713 51.733 m. 1300.0369 1296.2845 1292.0999 1294. 4479 1297. 4810 1295. 9552 1294.3130 1292. 8408 1380. 9586 1305. 5324 1301. 1317 1291.9117 1286. 5893 1286. 1500 1286 6180 1287. 1588 1288. 0042 1289. 5521 1292. 70S7 1297. 2382 1298. 4222 1300. 8219 1304. 8769 1306. 6223 1309. 9749 1310. 3245 1312. 784S 1315. 615C 1317.3583 iiWo. ie42 1287. 3999 1287. 3208 1288. 2386 1287.6456 1287.3311 1288. 7897 1290. 1242 1290. 5056 1290. 1962 1291.6814 1293. 1986 1293. 3278 1294. 1779 1293. 6415 1291.4165 1294.0525 1288. 7049 1288.3736 1288.3270 1288. COM 1287. 7105 1288. 0251 U80. sen 1292. 9822 12%. 3667 1295.0717 1295.3815 1296. 3398 1301. 2342 1311.1886 1323. 7802 1328. 7618 1333. 3770 1331. 4552 1344. 6582 1359. 4594 1374.8861 1391. 4459 1407. 7893 1420.5547 1437.8327 1452. 4372 1467. 4631 1482.9489 1481.4473 PRECISE LEVELING, BKIGHAM TO SAN FRANCISCO. Results of leveling, Brigham, Utah, to Beowawe, Nev. — Continued. 9 Date. 1911 Inly 27-27 July 28-27 July 27-28 July 28-Aug. 4. Do Do Do July 28-29 Do Do Do Do Do July 29-29 Do July31-31 Aug. 2-2 July 31-31 Do Aug. 2-2 July 31-31 Aug. 2-2 July 31-31 Do July 31-Aug. 2. Aug. 2-2 Aug. 3-3 Aug. 2-2 Do Aug. 2-3 Aug. 3-3 Do Do Aug. 7-7 Do Do Do Aug. 9-9 Do Do Do Do Aug. 10-10 Do Do Do Aug. 10-11 Do Aug. 11-11 Do Do Do Aug. 11-12 Do Aug. 12-12 Do Vug. 19-19 Do Do Do Do Do Do Aug. 19-22 Do Aug. 14-14 Do Do Do Do Do Aug. 14-15 Do Aug. 15-15 Do Do Do Aug. 15-16 Aug. 16-16 Do Do Do Do Aug. 17-16 Aug. 16-17 Aug. 17-17 Do Aug. 18-18 Aug. 17-17 Do From B. M. B. M. to 61-62 62-63 63-Y, Yr-64 64-65 65-66 66-Z, Z,r67 67-68 68-69 69-70 70-A,o A iir71 71-72 72-B,o B 10-73 B,o-73 73-74 74-75 74-75 75-Cio 75-Cio Co-76 76-77 77-78. 78-79 78-79 79-80 80-Dio D ,0-81 81-82 82-83 83-E, E.o-84 84-85 85-86 86-87 87-F,o Fio-88 88-89 89-90 90-91 91-Gio G,o-92 92-93 93-94 94-95 95-96 96-Hio Hio-97 97-98 99-100 100-101 lOl-I.o 101-I,o I,o-102 102-103 103-104 104-105 105-106 106-Jio J, 0-107 107-108 108-K.o K,o-109 K,o-109 109-110 110-111 111-112 112-113 113-114 114-115 115-L,o L.o-116 116-117 117-118 118-119 119-Mi„ 119-M, M,o-120 120-121 121-122 121-122 122-Nio N,o-123 123-124 123-124 124-125 125-126 Dis- tance in kilo- me- ters. 1.027 0.947 0.782 1.025 1.171 1.174 0.524 0.974 1.026 1.154 1.035 0.427 1.071 1.102 1.729 1.288 1.288 1.173 1.156 1.156 0.788 0.788 1.125 1.137 1.322 1.201 1.201 0.990 0.712 1.476 1.045 0.980 1.328 1.514 1.09G 1.247 1.281 1.044 1.230 1.089 1.096 1.148 0.922 0.567 1.183 1.165 1.039 1.165 1.006 1.140 0.937 1.186 1.190 1.001 1.083 1.083 0.975 1.097 1.199 1.090 1.359 1.090 1.129 0.926 1.551 1.079 1.079 1.026 1.225 1.101 1.065 1.066 1.077 1.450 1.024 1.043 1.027 1.037 0.627 0.627 1.028 1.152 1.061 1.061 1.663 1.151 1.080 1.080 1.037 1.025 Difference of elevation. Forward line. m. + 6.5173 + 5.5724 + 0.5000 - 2.3035 - 2.9050 - 4.0912 - 0. 1363 - 4.6886 -13.7523 -13.6138 -10.1499 - 1.4078 - 8.3503 -13.3475 -19.4542 - 4.3392 - 4.3418 + 7.4020 + 1.9302 + 1.9320 - 6.0788 - 6.0804 - 6.5148 -14.2508 -15.2620 -15.2976 -15.3035 -12.1599 - 9.8945 -17.1452 -13.2580 - 9. 7977 - 1.1365 + 0.0424 - 0.0501 - 0.0383 - 0.0356 + 3.0519 - 1.4176 + 0.0670 + 0.2706 + 1.4713 + 0.6391 + 0.3741 - 0.2180 4- 1.6830 + 1.9174 + 3.1361 - 2.6467 - 3.0171 - 1.3460 - 1.6523 + 0.5055 + 0.5163 - 0.40SO - 0.4112 + 0.3731 - 0.2443 - 0.4785 - 1.0812 - 0.3526 + 0.7974 - 0.6697 + 0.9834 + 0.3567 + 0. 4631 + 0.4594 + 0.54S1 - 1.5512 + 0.4926 + 0.5146 + 6.3794 +13.3915 +19.2418 +11.5834 +11.9673 +11.9756 +12.8233 + 9.5497 + 9.5513 + 11.1290 +14.5343 +13.3493 +13.3542 +13.4530 -13.4437 + 0.6167 + 0.6156 - 7.7885 - 4.6399 Back- ward line. 771. - 6.5188 - 5.5725 - O.5O03 + 2.3047 + 2.9036 + 4.0874 + 0. 1360 + 4.6875 +13. 7490 +13.6138 + 10.1525 + 1.4075 + 8.3508 +13.3493 +19.4525 + 4.3480 + 4.3434 - 7.4053 - 1.9360 - 1.9335 + 6.0829 + 6.0817 + 6.5127 +14.2512 +15.2625 + 15.3040 +15.3018 + 12.1624 + 9.8965 + 17.1494 +13. 2599 + 9.7979 + 1.1335 - 0.0398 + 0.0520 + 0.0364 + 0.0356 - 3.0504 + 1.4187 - 0.0698 - 0.2717 - 1.4692 - 0.6371 - 0.3755 + 0.2187 - 1.6840 - 1.9187 - 3.1342 + 2.6489 + 3.0180 + 1.3459 + 1.6523 - 0.5072 - 0.5161 0. 4126 f 0.4111 - 0.3716 + 0.2435 + 0.4784 + 1.0775 + 0.3550 - 0.7936 + 0.6720 - 0.9825 - 0.3582 - 0.4591 - 0.54S0 + 1.5535 - 0.4936 - 0.5128 - 6.3820 -13.3940 -19.2464 -11.5840 -11.9658 -11.9764 -12.8218 - 9.5539 - 9.5531 -11.1310 -14.5341 -13.3559 -13.3520 -13.4572 + 13.4463 - 0.6160 + 7.7849 + 4.6419 Mean. + 6.5180 + 5.5724 + 0.5002 - 2.3041 - 2.9043 - 4.0893 - 0. 1362 - 4.6880 -13. 7506 -13.6138 -10. 1512 - 1.4076 - 8.3506 -13.3484 -19.4534 - 4.3431 + 7.4036 + 1.9330 - 6.0810 - 6.5138 -14.2510 -15.2622 -15.3018 -12.1612 - 9.8955 -17.1473 -13.2590 - 9.7978 - 1.1350 + 0.0411 - 0.0510 - 0.0374 - 0.0356 + 3.0512 - 1.4182 + 0.0684 + 0.2712 + 1.4702 + 0.6381 + 0.3748 - 0.2184 + 1.6835 + 1.9180 + 3.1352 - 2.6478 - 3.0176 - 1.3460 - 1.6523 + 0.5064 + 0.5162 - 0.4107 + 0.3724 - 0.2439 - 0.4784 - 1.0794 - 0.3538 + 0.7955 - 0.6708 + 0.9830 + 0.3574 + 0.4602 + 0.5480 - 1.5524 + 0.4931 + 0.5137 + 6.3807 + 13.3928 + 19.2441 + 11.5837 + 11.9666 +11.9760 +12.8226 + 9.5520 + 11.1300 +14.5342 +13.3529 +13.4551 -13.4450 + 0.6161 - 7.7867 - 4.6409 Discrepancy. Par- tial. mm + 1.5 +0.1 +0.3 -1.2 +1.4 +3.8 +0.3 +1.1 +3.3 0.0 -2.6 +0.3 -0.5 -1.8 + 1.7 -5.2 +3.3 +3.7 -2.7 + 2.1 -0.4 -0.5 -2.3 -2.5 -2.0 -4.2 -1.9 -0.2 +3.0 -2.6 -1.9 +1.9 0.0 -1.5 -1.1 +2.8 + 1.1 -2.1 -2.0 + 1.4 -0.7 +1.0 + 1.3 -1.9 -2.2 -0.9 +0.1 0.0 + 1.7 -0.2 -2.2 -1.5 +0.8 +0.1 +3.7 -2.4 -3.8 -2.3 -0.9 +1.5 -2.1 -0.1 -2.3 +1.0 -1.8 +2.6 +2.5 +4.6 +0.6 -1.5 +0.8 -1.6 +3.0 +2.0 -0.2 +2.2 +4.2 -2.6 -0.2 +3.6 -2.0 Total accu- mu- lated. mm. + 9.4 + 9.5 + 9.8 + 8.6 + 10.0 +13.8 +14.1 +15.2 + 18.5 + 18.5 + 15.9 + 16.2 + 15.7 + 13.9 + 15.6 +10.4 +13.7 +17.4 +14.7 + 16.8 + 16.4 + 15.9 +13.6 +11.1 + 9.1 + 4.9 + 3.0 + 2.8 + 5.8 + 3.2 + 1.3 + 3.2 + 3.2 + 1.7 + 0.6 + 3.4 + 4.5 + 2.4 + 0.4 + 1.8 + 1.1 + 2.1 + 3.4 + 1.5 - 0.7 - 1.6 - 1.5 - 1.5 + 0.2 0.0 - 2.2 -3.7 -2.9 - 2.8 + 0.9 - 1.5 -5.3 - 7.6 - 8.5 - 7.0 - 9.1 -9.2 -11.5 -10.5 -12.3 -9.7 - 7.2 -2.6 - 2.0 - 3.5 -2.7 - 4.2 - 1.2 + 0.8 + 0.6 + 2.8 + 7.0 + 4.4 + 4.2 Designation ofB. M. 62 63 Y, 64 65 66 Z, 67 68 69 70 A io 71 72 B,o 73 74 75 Cio 76 77 78 80 D,o 81 82 83 E,o 84 85 86 87 F,o 88 89 90 91 G,o 92 93 94 95 96 H,o 97 98 99 100 101 102 103 104 105 106 J io 107 108 Kio 109 110 111 112 113 114 115 Lio 116 117 118 119 120 121 122 N,o 123 125 126 Distance from B.M. R. fem 52. 760 53. 707 54.489 55. 514 56.685 57. 859 58. 383 59.357 60.383 61. 537 62. 572 62.999 64. 070 65. 172 66.901 68.189 69. 362 70.518 72. 431 73.568 74.890 76.091 77.081 77.793 79. 209 80. 314 81.294 82.622 84.136 85.232 86.479 87. 760 88.804 90.034 91.123 92. 219 93.367 94. 289 94.856 96. 039 97. 204 98. 243 99.408 100. 414* 101.554 102. 491 103. 677 104. 867 105. 868 106.951 107.926 109.023 110.222 111.312 112. 671 113. 761 114.890 115.816 117.367 118.446 119.472 120.697 121.798 122.863 123.929 125.006 126. 456 127.480 128.523 129.550 130.587 131.214 132. 242 133.394 134.455 136. 118 137.269 138.349 139.386 140.411 Observed elevation above mean sea level. m. 1487.9653 1493. 5377 1494.0379 1491. 7338 1488. 8295 1484. 7402 1484. 6040 1479. 9160 1466. 1654 1452. 5516 1442. 4004 1440. 9928 1432. 6422 1419. 2938 1399. 8404 1395. 4973 1402.9009 1404. 8339 1392. 2391 1377.9881 1362. 7259 1347.4241 1335. 2629 1325. 3674 1308. 2201 1294.9611 1285. 1633 1284. 0283 1284. 0694 1284. 0184 1283. 9810 1283.9454 1286. 9966 1285. 5784 1285. 6468 1285.9180 1287.3882 1288.0263 1288. 4011 1288. 1827 1289. 8662 1291.7842 1294.9194 1292. 2716 1289. 2540 1287. 9080 1286. 2557 1286. 7621 1287. 2783 1286. 8676 12S7.2400 1286. 9961 1286. 5177 1285.4383 1285.0845 1285. 8800 1285. 2092 1286.1922 1286. 5496 1287. 0098 1287. 5578 1286.0054 128G. 4985 1287.0122 1293. 3929 1306. 7857 1326.0298 1337.6135 1349. 5801 1361.5561 1374. 3787 1383.9307 1395.0607 1409.5949 1422.9478 1436.4029 1422.9579 1423.5740 1415. 7873 1411.1464 10 U. S. COAST AND GEODETIC SURVEY SPECIAL PUBLICATION NO. 22. Results of leveling, Brigham, Utah, to Beowawe, Nev. — Continued. Date. From B. M. to B. M. Dis- tance in kilo- me- ters. Difference of elevation. Forward line. Back- ward line. Mean. Discrepancy. Par- tial. Total accu- mu- lated. Designation ofB. M. Distance from B. M. K. Observed elevation above mean sea level. 1911. Aug. 18-18 Aug. 21-21 Aug. 18-18 Do Do Do Aug. 21-21 Aug. 25-25 Aug. 21-21 Do Do Aug. 26-21 Aug. 26-26 Do Do Do Do Do Aug. 26-27 Aug. 27-27 Do Do Do Do Do Aug. 28-28 Do Do Do Aug. 29-30 Aug. 28-28 Do Do Do Aug. 29-29 Do Do Aug. 29-28 Aug. 29-29 Do Do Aug. 30-30 Do Do Do Do Aug. 31-31 Do Do Do Do Do Aug. 31, Sept. 1 Sept. 1-1 Do Do Sept. 1-2 Sept. 2-2 Do Do Sept. 13-13 Do Sept. 12-12 Sept. 13-13 Sept. 12-12 Do Sept. 11-11 Do Do Do Do Sept. 8-8 Sept. 13-13 Sept. 8-6 Do Sept. 8-8 Do Sept. 8-6 Do Sept. 7-7 Do Sept. 6-7 Sept. 7-8 Sept. 6-7 Sept. 7-7 Do Sept. 6-7 126-127 126-127 127-128 128-129 129-130 130-Oio 0,0-131 0„rl31 131-132 132-133 133-134 134-135 135-136 136-137 137-Pio Pio-138 138-139 139-140 140-141 141-142 142-143 143-144 144-145 145-146 146-Q,„ Qlo-147 147-148 148-R,o Rlo-149 Klo-149 149-150 150-151 151-152 152-153 153-Sio Sio-154 154-155 155-156 156-157 157-158 158-159 159-160 160-T,o T 10 -161 161-162 162-163 163-164 164-165 165-U,o U,o-166 166-167 167-168 168-169 169-170 170-171 171-V 10 V,o-172 172-173 173-174 174-175 175-176 176-Wio i7o-X,o 176-X.o Xio-Y,o Y,o-177 177-178 178-Zio Znr-179 179-An A„-180 180-181 180-181 181-182 182-183 183-I 3 13-184 184-185 185-186 186-J 3 Jn-187 187-188 187-188 1SS IS!) 189-Ks Kj-190 190-tfll 1.077 1.077 1.031 1.021 1.013 0.916 1.007 1.007 1.114 1.019 1.038 1.017 1.128 1.024 1.167 1.183 1.022 1.120 1.077 1.184 1.139 1.173 1.260 1.061 1.118 1.122 1.389 1.382 1.415 1.415 1.147 1.320 1.015 1.447 1.149 1.209 1.129 1.165 1.198 1.146 1.145 1.078 1.495 1.132 1.114 1.027 1.321 1.033 0.989 1.040 1.136 1.332 1.188 1.138 1.239 1.074 1.141 1.282 1.144 1.261 (U>61 0.924 771. + 1.6473 + 1.6503 - 1.7188 - 1.8733 + 0.1014 - 5.4012 - 5.9264 - 5.9284 + 0.1530 - 1.6055 + 0.2171 + 5.7854 - 1.1661 + 0.6430 - 1.8507 + 11.3422 + 12.3863 +14. 0272 - 0. 4365 - 7.0827 + 1.9171 - 7.3953 + 8.5200 + 4.3095 - 8.6213 -15.6756 -14. 7280 -11.2233 -10. 2636 -10. 2612 - 2.4311 - 4.4414 - 7.3303 - 5.4230 - 0.5656 - 1.0233 - 6.5939 - 8.9735 - 6.8566 - 6.6473 - 3. 2814 - 1.6055 + 3.4016 - 0.1042 + 2.1939 + 3.9711 + 4.9048 + 2.2998 + 0.9918 + 4.7387 + 2.2993 - 4.0720 - 1.6220 + 2.6970 + 1.9552 + 4.2243 +10.9882 + 8.65S5 + 3.4905 - 1.5667 - 5. 5739 TO. - 1.6515 - 1.6531 + 1.7176 + 1.8750 - 0.1014 + 5.4006 + 5.9336 + 5.9288 - 0. 1532 + 1.6050 - 0.2153 - 5. 7865 + 1.1666 - 0.6410 + 1.8509 -11.3444 -12.3862 -14.0249 + 0.4350 + 7.0819 - 1.9169 + 7.3927 - 8.5228 - 4.3086 + 8.6205 + 15.6775 + 14.7282 +11.2262 + 10.2685 +10.2615 + 2.4296 + 4.4439 + 7.3288 + 5.4206 + 0.5685 + 1.0270 + 6.5939 + 8.9716 + 6.8554 + 6.6495 + 3.2789 + 1.6070 - 3.4064 + 0.1034 - 2.1963 - 3.9709 - 4.9050 - 2.3006 - 0.9915 - 4.7359 - 2.3026 + 4.0759 + 1.6252 - 2.6995 - 1.9556 - 4.2235 -10.9876 - 8.6612 - 3.4914 + 1.5640 + 5.5722 + 1.6506 - 1.7182 - 1.8742 + 0.1014 - 5.4009 - 5.9293 + 0.1531 - 1.6052 + 0.2162 + 5.7860 - 1.1664 + 0.6420 - 1.8508 +11.3433 + 12.3862 + 14.0260 - 0.4358 - 7.0823 + 1.9170 - 7.3940 + 8.5214 + 4.3090 - 8.6209 -15.6766 -14. 7281 -11.2248 -10.2637 - 2.4304 - 4.4426 - 7.3296 - 5.4218 - 0.5670 - 1.0252 - 6.5939 - 8.9726 - 6.8560 - 6.6484 - 3.2802 - 1.6062 + 3.4040 - 0.1038 + 2.1951 + 3.9710 + 4.9049 + 2.3002 + 0.9916 + 4.7373 + 2.3010 - 4.0740 - 1.6236 + 2.6982 + 1.9554 + 4.2239 +10.9879 + 8.6604 + 3.4910 - 1.5654 - 5.5730 +3.5 +1.2 -1.7 0.0 +0.6 -3.8 +0.2 +0.5 -1.8 +1.1 -0.5 -2.0 -0.2 + 2.2 -0.1 -2.3 + 1.5 +0.8 -0.2 +2.6 +2.8 -0.9 +0.8 -1.9 -0.2 -2.9 -2.6 +1.5 -2.5 + 1.5 +2.4 -2.9 -3.7 0.0 + 1.9 +1.2 -2.2 +2.5 -1.5 +4.8 +0.8 +2.4 -0.2 +0.2 +0.8 -0.3 -2.8 +3.3 -3.9 -3.2 +2.5 +0.4 -0.8 -0.6 +1.7 +0.9 +2.7 + 1.7 mm. + 9.3 + 10.5 0.4 5.6 5.8 6.3 4.5 5.6 5.1 3.1 2.9 5.1 + 5.0 + 2.7 + 4.2 + 5.0 + 4.8 + 7.4 +10.2 + 9.3 +10.1 + 8.2 + 8.0 + 5.1 + 2.5 + 4.0 + 1.5 + 3.0 + 5.4 + 2.5 - 1.2 - 1.2 + 0.7 + 1.9 0.3 + 2.2 + 0.7 + 5.5 + 6.3 + 8.7 + 8.5 + 8.7 + 9.5 + 9.2 + 6.4 + 9.7 + 5.8 + 2.6 + 5.1 + 5.5 + 4.7 + 4.1 + 5.8 + 6.7 + 9.4 +11.1 3.3049 1TT1T 1.111 0.800 1.239 1.133 1.197 1.649 1.133 0.752 0.747 0.747 1.189 1.091 0.714 0.514 1.092 1.215 1.045 0.952 1.107 1.107 0.847 0.712 1.049 1.154 + 3.9260 + 3. 9277 + 8.1908 + 6.8279 + 1.7516 + 0.4621 + 9.2927 + 8.9098 + 4.6038 + 8.1766 + 8. 1762 + 14.9945 +14.5334 + 9.9736 + 4.5540 + 2.8152 + 0. 1954 + 1.9219 - 2.3162 + 0.4453 + 0.4503 + 1.5376 - 0. 1124 + 1.6573 + 0.6836 + 3.3042 I - :i.iVii7 - 3.9302 - 8.1901 - 6.8264 - 1.7539 - 0.4641 - 9.2898 - 8.9093 - 4.6027 - 8. 1721 - 8.1774 -14.9907 -14.5336 - 9.9705 - 4.5552 - 2.8164 - 0.1974 - 1.9249 + 2.3132 - 0.4525 - 0.4516 - 1.5384 + 0.1124 - 1.6552 - 0.6840 3.3046 I +0.7 +11.8 I + 3.9289 + 8.1904 + 6.8272 + 1.7528 + 0.4631 + 9.2912 + 8.9096 + 4.6032 + 8.1756 + 14.9926 + 14.5335 + 9.9720 + 4.5546 + 2.8158 + 0. 1964 + 1.9234 - 2.3147 + 0.4499 + 1.5380 - 0.1124 + 1.6562 + 0.6838 +4.2 +15.3 -0.7 + 14.6 -1.5 + 13.1 +2.3 +15.4 +2.0 +17.4 -2.9 +14.5 -0.5 +14.0 -1.1 + 12.9 -1.6 +11.3 -3.8 + 7.5 +0.2 + 7.7 -3.1 + 4.6 +1.2 + 5.8 +1.2 + 7.0 +2.0 + 9.0 +3.0 + 12.0 +3.0 + 15.0 +4.2 +19.2 +0.8 +20.0 0.0 +20.0 -2.1 + 17.9 +0.4 +18.3 127 128 129 130 O,o 132 133 134 135 136 137 P10 138 139 140 141 142 143 144 145 146 Q,o 147 148 R,o 149 150 151 152 153 S10 154 155 156 157 158 159 160 T,o 161 162 163 164 165 U,o 166 167 168 169 170 171 V,o 172 173 174 175 176 km. 141.488 142. 519 143.540 144.553 145. 469 146.476 147. 590 148. 609 149. 647 150.664 151.792 152. 816 153.983 155.166 156. 188 157. 308 158.385 159. 569 160. 708 161.881 163.141 164.202 165.320 166.442 167. 831 169. 213 170.628 171.775 173.095 174.110 175.557 176. 706 177.915 179.044 180.200 181.407 182.553 183. 698 184. 776 186.271 187.403 188.517 189.544 190.865 191. 898 192. 887 193. 927 195.063 196. 395 197. 583 198. 721 199.960 201.034 202. 175 203. 457 204.601 205.862 206.423 2077347 I X,o Y,o 177 178 Z,o 179 A,. 180 181 182 183 Is 184 185 186 h 187 188 190 191 TO. 1412. 7970 1411.0788 1409.2046 1409.3060 1403.9051 1397.9758 1398. 1289 1396. 5237 1396. 7399 1402. 5259 1401. 3595 1402. 0015 1400. 1507 1411. 4940 1423. S802 1437. !II«J2 1437. 4704 1430.3881 1432. 3051 1424.9111 1433. 4325 1437. 7415 1429. 1206 1413.4440 1398. 7159 1387.4911 1377.2274 1374. 7970 1370.3544 1363. 0248 1357.6030 1357. 0360 1356. 0108 1349. 4169 1340.4443 1333.5883 1326.9399 1323. 6597 1322. 0535 1325. 4575 1325.3537 1327. 5488 1331.5198 1336. 4247 1338. 7249 1339. 7165 1344. 4538 1346. 7548 1342.6808 1341.0572 1343. 7554 1345. 7108 1349.9347 1360.9226 1369. 5830 1373.0740 1371.5086 1365. 9356 1362. Mio 207.534 208. 334 209. 573 210. 706 211.903 213.552 214.685 215.437 216. 184 217.373 218.464 219. 178 219. 692 220.784 221.999 223.044 223.996 225.103 225.950 226.662 227.711 22v. Mi", 1369. 8645 1378. 0549 1384. 8821 1386. 6349 1387.0980 1396. 3892 1405. 2988 1409.9020 1418.0776 1433.0702 1447. 6037 1457.5757 1462. 1303 1464.9461 1465.1425 1467.0659 1464. 7512 1465.2011 1466.7391 1466. 6267 1468.2829 146S.9667 PRECISE LEVELING, BEIGHAM TO SAN FRANCISCO. Results of leveling, Brigham, Utah, to Beowawe, Nev. — Continued. 11 Date. 1911 Sept. 9-7 Sept. 9-9 Do Do Do........ Sept. 9-14 Sept. 14-H.... Do Do Do Do Do Do Sept. 15-15.... Do Do Do Do Sept. 16-16 Do Sept. 16-18 Sept. 18-18 Sept. 16-16 Sept. 18-19 Sept. 19-19 Sept. 16-18 Sept. 18-18 Do Do Do Sept. 19-19 Sept. 18-18 Do Sept. 19-19 Do Sept. 20-20 Do Do Do Oct. 12-12 Oct. 12-11 Do Do Do Do Oct. 10-11 Oct. 11-11 Oct. 10-11 Do Oct. 9-11 Do Do Oct. 11-11 Oct. 9-10 Oct. 10-8 Oct. 11-10 Oct. 10-8 Oct. 8-8 Do Oct. 8-7 Do Do Do Sept. 28-28 Do Do Oct. 7-7 8ept. 28-28 Do Sept. 28-29 Sept. 29-29 Do Do Do Do Do Sept. 29-30 Do Do Sept. 30-30 Do Do Oct. 2-2 Do Do Oct. 2-Sept. 30 Sept. 30-Oct. 2 Oct. 2-Sept. 30 Do From B. M. to B. M. 191-La Lj-Mj Mj-192 192-Nj N3-O3 Os-Pj O3-P3 Ps-193 193-194 194-Qj Qj-195 195-196 196-Rj Rj-197 197-198 198-S 3 Ss-199 199-200 200-Ts Tj-201 201-202 201-202 202-203 202-203 202-203 203-Us Uj-204 204-205 204-205 205-206 205-206 206-207 207-208 208-V, Vj-209 209-Ws Wa-X, Xj-210 210-211 211-Y, Yj-212 212-Z 3 Zj-213 213-214 214-A, A,-215 A,-215 215-216 216-B, B,-217 217-218 218-219 219-C4 C-220 220-221 220-221 221-D, D,-222 222-223 223-224 224-225 225-226 226-E, E,-227 227-F, F,-228 F,-228 228-229 229-G, 0,-230 230-231 231-232 232-233 233-234 233-234 234-H, H,-235 235-236 235-236 236-237 237-238 238-1, 1,-239 239-240 240-241 241-J, J,-242 242-243 243-244 Dis- tance in kilo- me- ters. 1.043 1.211 1.368 0.754 1.739 0.110 0.110 1.352 1.034 1.292 1.234 1.172 1.360 1.215 1.172 1.237 1.145 1.131 1.429 1.186 1.124 1.124 1.030 1.030 1.030 1.272 1.107 1.132 1.132 1.131 1.131 0.989 1.106 0.691 1.274 1.386 1.180 1.208 1.138 0.568 1.096 1.306 0.956 0.685 0.995 1.196 1.196 1.217 0.998 1.053 1.216 1.135 1.551 0.748 1.216 1.216 1.266 1.249 1.400 1.234 1.132 1.133 1.145 1.292 1.034 0.843 0.843 1.132 1.051 0.993 0.625 1.217 1.215 1.218 1.218 1.311 1.218 1.218 1.218 1.310 1.316 1.058 0.970 1.255 1.312 1.200 0.726 1.010 1.196 Difference of elevation. Forward line. m. - 0.0558 + 2.3125 + 3.2863 + 2.3382 + 8.6578 - 0.0067 - 0.0087 + 7.8885 + 6.6240 +16.4304 + 11.3662 +13.3076 + 18.3972 +13. 4313 +13.3380 + 17.4624 + 12.0540 + 14.7454 + 18.4028 +12. 5411 +13.4927 +13.4930 + 13.2371 +13.2346 + 13.2363 +17.4607 +14.0745 + 12.7202 + 12.7226 + 12.2456 + 12.0727 +14.6130 + 9.5153 +15.2193 + 8.7892 + 4.5775 + 8.2619 + 7.9429 + 5.0420 +11.9147 + 7.2487 - 1.4950 + 0.0651 + 3.0139 + 4.0099 4.0085 + 1.0121 + 2.4372 + 3.4181 + 4.1818 + 3.8629 + 4.5242 - 0.9731 - 2.2333 - 2.2342 + 1.1550 - 4.3837 + 1.0490 + 2.0865 - 1.6183 + 4.5777 + 1.2201 - 5.3534 - 3.7600 - 2.6560 - 2.6530 - 2.3218 - 1.2055 - 4.5654 - 1.3392 1.0484 + 2.1954 + .•!.»,s7ii 1866. 5675 1870. 4291 1874. 9533 1873. 9806 1871. 7446 1872. 9004 1S6S.5168 1869.5664 1871.6540 1870. 0370 187'.. 6145 1875. 8347 1870. 4818 1866. 7207 1864.0677 1861. 7463 1860.5411 1855. 9769 1854. 6373 1855. 6845 1857. 8799 1861. 7807 1866. 2041 1865.7129 1865.8573 1869. 0558 1874. 2318 1877.5004 1869.3348 1852. 4450 1835. 3773 1819. 3843 1813. 6778 1804. 0974 1789.6608 12 U. S. COAST AND GEODETIC SUKVEY SPECIAL PUBLICATION NO. 22. Results of leveling, Brigham, Utah, to Beovjawe, Nev.- — Continued. Date. FromB.M. to B. M. Dis- tance in kilo- me- ters. Difference of elevation. Forward line. Back- ward line. Discrepancy. Mean. Par- tial. Total accu- mu- lated. Designation ofB.M. Distance from B. M. R Observed elevation above mean sea level. 1911 Oct. 2-Sept. 29 Do Sept. 27-27 Do Sept. 30-Oct. 2 Sept. 27-27 Do Do Do Do Do Do Oct. 3-3 Do Do Do Do Do Do Oct. 3-4 Oct. 4-4 Do Do Do Do Do Do Oct. 5-5 Do Do Do Oct. 6-6 Oct. 5-5 Do Oct. 6-6 Do Do Do Oct. 6-15 Oct. 15-15 Do Do Oct. 14-15 Oct. 14-14 Do Do Do Do Do Do Do Oct. 16-16 Do Do Do Do Do Do Do Oct. 17-17 Oct. 20-20 Do Do Do Do Oct. 21-21 Do Do Oct. 23-21 Oct. 23-23 Oct. 23-21 Oct. 23-23 Do Do Oct. 23-24 Oct. 24-24 Do Do Do Do Oct. 24-25 Oct. 25-25 Do Do Oct. 25-26 244-K, v IS. P. B. M.I JM \ 5803. 200/ rs. P. B. M.i 245 \ 5803.200/ 245-L 4 245-L« L ( -246 246-M» M,-N, N 4 -247 247-0, 0,-P ( P<-248 248-Q< Q.-249 249-250 250-251 251-252 252-253 253-R t „ IS. P. B. M.\ "H 5483.658/ IS. P. B. M.l_„,, \ 5483.658/"" 254-255 255-256 256-257 257-258 258-259 259-S* S ( -260 260-261 261-262 262-T ( 262-T ( 1V263 263-U< U<-264 264-265 265-266 266-267 267-V, V.-268 269-270 270-271 271-272 272-273 273-274 274-275 275-276 276-277 277-278 278-W, 'W 4 -279 279-280 280-281 281-X, X 4 -282 282-283 283-284 284-285 285-Y, Y ( -286 286-287 287-288 288-289 289-Z 4 Z ( -A s As-290 As-290 290-291 290-291 291-U S B 6 -292 292-293 293-294 294-295 295-296 296-297 297-Cs Cs-298 298-Ds Ds-299 299-300 300-E s E 6 -F 6 F,-G, 1.089 0.914 1.204 1.114 1.114 1.193 1.183 0.048 1.486 1.010 1.620 1.247 1.943 1.275 1.216 1.153 1.214 1.091 0.797 1.043 1.419 1.194 1.134 1.093 1.094 1.254 0.454 ,1. 096 1.216 1.134 0.969 0.969 1.134 1.828 1.129 1.071 1.134 1.612 0.547 1.484 1.045 1.044 0.805 1.215 1.215 1.487 1.433 1.283 0.936 1.147 1.423 1.491 1.226 1.289 1.224 1.170 1.104 1.028 0.834 0.172 0.874 1.097 1.090 1.174 1.111 1.179 1.056 1.056 1.305 1.305 1.209 1.046 1.130 1.133 1.134 0.529 1.093 1.135 1.708 1.486 1.059 0.730 1.158 1.096 1.056 -12.8173 - 8.0485 -15.2525 -13.6658 -13.6595 -16.5263 - 8.1865 - 0.0640 - 0.5494 - 2.9426 - 2.6224 - 2.3685 - 1.5955 - 6.7766 - 4.3174 - 4.6228 - 4.7727 - 4.1223 - 3.2998 - 3.8903 - 5.5783 - 4.5609 - 4.4741 - 4.0916 - 4.2600 - 4.7446 - 1.3706 - 4.8539 - 4.8953 - 2.2207 - 1.1546 - 1.1548 - 1.4564 - 3.8368 - 3.6749 - 2.2035 - 2.0381 - 1.9049 - 2.0633 - 1.5179 - 2.3227 + 0.7454 - 2.8692 - 2.2084 - 2.2836 - 1.2744 - 2.4785 - 1.2316 - 2.8656 - 1.4568 + 0.3763 - 5.9367 - 0.8445 - 2.3539 + 0.7396 - 3.1209 - 1.7392 - 1.5923 + 0.0314 + 0.3424 - 1.4552 - 3.5787 - 2.2296 - 2.4414 + 1.7163 - 1.6455 - 0.7892 - 4.5402 - 4.5414 - 0.5745 - 3.9125 - 1.9870 + 3.6706 - 0.8928 - 4.9191 - 4.9188 - 2.8903 - 1.9427 + 3.1304 - 8.1607 - 1.4375 + 1.1518 + 1.5885 - 3.7920 - 3.5257 m. +12.8157 + 8.0472 +15.2514 + 13.6582 +13.6594 +16.5242 + 8.1873 + 0.0643 + 0.5497 + 2.9431 + 2.6217 + 2.3717 + 1.5957 + 6.7781 + 4.3215 + 4.6256 + 4.7743 + 4.1206 + 3. 2975 + 3.8868 + 5.5784 + 4.5637 + 4.4726 + 4.0886 + 4.2610 + 4.7434 + 1.3720 + 4.85.58 + 4.8944 + 2.2235 1. 1592 + 1.1561 + 1.4560 + 3.8350 + 3.6748 + 2.2055 + 2.0392 + 1.9031 + 2.0637 + 1.5143 + 2.3224 - 0.7450 + 2.8675 + 2.2075 + 2.2807 + 1.2781 + 2.4766 + 1.2319 + 2.8683 + 1.4546 - 0.3785 + 5.9364 + 0.8440 + 2.3526 - 0.7388 + 3.1220 + 1.7361 + 1.5933 - 0.0328 - 0.3431 + 1.4559 + 3.5824 + 2.2311 + 2.4456 - 1.7137 + 1.6441 + 0.7841 + 0.7861 + 4.5461 + 4.5397 + 0.5757 + 3.9116 + 1.9847 - 3.6726 + 0.8928 + 4.9160 + 4.9172 + 2.8891 + 1.9387 - 3.1279 + 8.1652 +1.4367 - 1.1524 - 1.5892 + 3.7945 + 3.5280 -12.8165 - 8.0478 -15.2520 }- 13.6607 -16.5252 8.1869 0.0642 0.5496 2.9428 2.6220 2. 3701 1.5956 6. 7774 4.3194 4.6242 4.7735 4. 1214 3.2986 - 5.5784 - 4.5623 - 4.4734 - 4.0901 - 4.2605 - 4. 7440 - 1.3713 - 4.8548 - 4.8948 - 2.2221 - 1.1562 - 1.4562 - 3.8359 - 3.6748 - 2.2045 - 2.0386 - 1.9040 - 2.0635 - 1.5161 - 2.3226 + 0.7452 - 2.8684 - 2.2080 - 2.2822 - 1.2762 - 2.4776 - 1.2318 - 2.8670 - 1.4557 + 0.3774 - 5.9366 - 0.8442 - 2.3532 + 0.7392 - 3. 1214 - 1.7376 - 1.5928 + 0.0321 + 0.3428 - 1.4556 - 3.5806 - 2.2303 - 2.4435 + 1.7150 - 1.6448 - 0.7872 - 4.5418 - 0.5751 - 3.9120 - 1.9858 + 3.6716 - 0.8928 - 4.9178 - 2.8897 - 1.9407 + 3. 1292 - 8.1630 - 1.4371 + 1.1521 + 1.5888 - 3.7932 - 3.5268 + 1.6 + 1.3 +1.1 +3.8 +2.1 -0.8 -0.3 -0.3 -0.5 +0.7 -3.2 -0.2 -1.5 -4.1 -2.8 -1.6 +1.7 +2.3 +3.5 -0.1 -2.8 + 1.5 +3.0 -1.0 +1.2 -1.4 -1.9 +0.9 -2.8 -2.9 +0.4 +1.8 +0.1 -2.0 -1.1 + 1.8 -0.4 +3.6 +0.3 -0.4 +1.7 +0.9 +2.9 -3.7 +1.9 -0.3 -2.7 +2.2 + 2.2 +0.3 +0.5 + 1.3 -0.8 -1.1 +3.1 -1.0 + 1.4 +0.7 -0.7 -3.7 -1.5 -4.2 -2.6 + 1.4 +4.1 -2.1 -1.2 +0.9 +2.3 +2.0 0.0 +2.4 +1.2 +4.0 -2.5 -4.5 +0.8 +0.6 +0.7 -2.5 -2.3 mm. +56.6 +57.9 +59.0 +62.8 +64.9 +64.1 +63.8 +63.5 +63.0 +63.7 +60.5 +60.3 +58.8 +54.7 +51.9 +50.3 +52.0 +54.3 +57.8 +57.7 +54.9 +56.4 +59.4 +58.4 +59.6 +58.2 +56.3 +57.2 +54.4 +51.5 +51.9 +53.7 +53.8 +51.8 +50.7 +52.5 +52.1 +55.7 +56.0 +55.6 +57.3 +58.2 +61.1 +57.4 +59.3 +59.0 +56.3 +58.5 +60.7 +61.0 +61.5 +62.8 +62.0 +60.9 +64.0 +63.0 +64.4 +65.1 +64.4 +60.7 +59.2 +55.0 +52.4 +53.8 +57.9 +55.8 +54.6 +55.5 +57.8 +59.8 +59.8 +62.2 +63.4 +67.4 +64.9 +60.4 +61.2 +61.8 +62.5 +60.0 +57.7 IS. P. B. M.\ \ 5803. 200/ 245 L, 246 M ( N, 247 O4 P« 248 Q< 249 250 251 252 253 R< IS. P. B.M.I \ 5483. 658j 254 255 256 257 258 259 S< 260 261 T, 263 U, 264 265 266 267 V, 268 269 270 271 272 273 274 275 276 277 278 W 4 279 280 281 X, 282 283 284 285 Y, 286 287 Z, As 290 291 B 5 292 293 294 295 296 297 Cs 298 D 6 299 300 E 6 Fj Gt km. 318. 121 319.035 320.239 321. 353 322. 546 323.729 323. 777 325.263 326. 273 327. 893 329. 140 331.083 332. 358 333.574 334.727 335.941 337.032 337.829 338.872 340. 291 341.485 342. 619 343. 712 344.806 346.060 346. 514 347. 610 348. 826 349. 960 350.929 352.063 353.891 355.020 356.091 357.225 358.837 359. 384 360.868 361. 913 362. 957 363.762 364. 977 366. 192 367. 679 369. 112 370. 395 371.331 372. 478 373. 901 375.392 376. 618 377. 907 379. 131 380.301 381. 405 382. 433 383.267 383. 439 384. 313 385.410 386.500 387. 674 388. 785 389.964 391. 020 392. 325 393.534 394.580 395. 710 396. 843 397. 977 398.506 399.599 400. 734 402. 442 403. 928 404. 987 405.717 406. 875 407. 971 409.027 1776. 8443 1768. 7965 1753. 5445 1739. 8S38 1723. 3586 1715. 1717 1715. 1075 1714.5579 1711.6151 1708. 9931 1706. 6230 1705. 0274 1698. 2500 1693. 9306 1689. 3064 1684.5329 1680.4115 1677. 1129 1673. 2243 1667.6459 1663.0836 1658. 6102 1654.5201 1650. 25% 1645. 5156 1644. 1443 1639.2895 1634.3947 1632. 1729 1631. 0164 1629. 5602 1625. 7243 1622. 0495 1619. 8450 1617. 8064 1615. 9024 1613.8389 1612. 3228 1610. 0002 1610. 7454 1607. 8770 1605. 6690 1603.3868 1602. 1106 1599. 6330 1598. 4012 1595.5342 1594. 0785 1594.4559 1588. 5193 1587. 6751 1585.3219 1586. 0611 1582. 9397 1581.2021 1579.6093 1579. 6414 1579. 9842 1578. 5286 1574. 9480 1572. 7178 1570. 2742 1571. 9892 1570.3444 1569.5572 1565. 0154 1564.4403 150U. 52S3 1558. 5425 1562. 2141 1561.3213 1556. 4035 1553.5138 1551.5731 1554. 7023 1546. 5393 1545. 1022 1546. 2543 1547. 8431 1544. 0499 1540.5231 PRECISE LEVELING, BRIGHAM TO SAN FRANCISCO. Results of leveling, Brigham, Utah, to Beowawe, Nev. — Continued. 1.3 From B. M. to B. M. Dis- tance in kilo- me- ters. Difference of elevation. Discrepancy. Designation of B. M. Distance from B. M. R. Observed Date. Forward line. Back- ward line. Mean. Par- tial. Total accu- mu- lated. elevation above mean sea level. 1911. Oct. 25-25 G s -301 301-302 302-H s Hs-303 303-304 304-Is Is-Js Js-305 305-K 5 K 5 -306 305-307 307-L s L 5 -30S 308-309 309-M 6 Ms-310 310-311 311-Ns Ns-312 312-Os 312-Os Os-Ps Ps-Qs Qs-Rs Qs-Rs Rs-313 313-314 314-Ss Ss-315 315-316 315-316 316-317 317-Ts Ts-318 318-319 319- U 5 Us-320 320-V s Vs-321 321-322 322-323 323-324 324-325 325-326 326-327 327-Ws Ws-328 328-329 329-330 330-331 331-332 331-332 332-Xs Xs-333 333-334 334-335 335-336 336-337 337-Y s Ys-338 338-339 339-340 340-341 341-342 342-Z 5 Zi-343 343-344 344-345 345-346 346-347 347- A, A«-B, B.-C, 1.205 1.219 0.907 1.216 1.219 0.807 2.012 1.215 1.583 1.185 1.194 1.038 1.051 1.318 1.071 1.257 1.113 0.866 1.174 1.344 1.344 0.570 0.977 0.708 0.708 1.178 0.875 1.263 1.218 1.215 1.215 1.180 1.204 1.099 1.218 0.915 1.170 1.135 1.125 1.128 1.134 1.133 1.131 1.130 1.130 1.412 1.215 1.216 1.215 1.052 1.198 1.198 0.790 1.278 1.214 1.218 1.208 1.218 1.183 1.107 1.219 1.217 1.214 1.134 0.910 1.135 1.218 1.218 1.189 1.118 0.361 0.113 0.798 m. + 0.6262 — 4.4353 — 0.6312 — 0.9647 — 1.3286 — 0. 7961 — 2.8384 — 0.7290 — 2.8098 — 3.7441 — 0. 1237 + 3.4648 — 4.8499 — 2.7778 — 2.1646 — 0. 1935 — 1.1289 + 0.2275 — 0.2368 — 1.2427 — 1.2422 — 1.5432 — 2.0149 — 1.5248 — 1.5228 — 3.9112 — 0.3608 — 6. 1738 — 0.5666 — 2.1441 — 2.1384 — 1.0604 — 2.3531 / + 0.8354 \ + 0.8419 — 3.6317 — 2.3154 + 1.1616 — 3. 4481 + 0.3423 — 2.8622 — 1.2173 — 2.0310 — 0. 2677 — 1.1182 — 1.7050 — 0.0330 + 0.1362 — 1.2987 — 2. 1364 — 1.9905 — 1.2392 — 1.2400 — 0.5964 — 4.2556 — 1.2240 + 0.1044 — 4. 0076 — 4.1509 — 0.4290 — 2. 1292 — 4.6948 — 1.5940 — 2.0886 — 0. 7464 — 1.9546 — 2.0079 — 1.8545 — 1.6848 — 2.0433 — 1.5324 — 0.3037 — 0. 3501 — 1. 5218 m. — 0.6232 + 4.4338 + 0.6283 + 0.9628 + 1.3284 + 0.7954 + 2.8379 + 0.7286 + 2.8108 + 3. 7417 + 0.1243 — 3.4651 + 4.8508 + 2.7749 + 2.1644 + 0. 1958 + 1.1288 — 0.2246 + 0.2375 + 1.2380 + 1.2409 + 1.5438 + 2.0140 + 1.5196 + 1.5229 + 3.9081 + 0.3604 + 6.1719 + 0.5639 + 2. 1394 + 2.1410 + 1.0588 + 2.3498 — 0. 8414 — 0.8399 + 3.6345 + 2.3170 — 1. 1658 + 3.4466 — 0.3441 + 2.8615 + 1.2184 + 2.0282 + 0.2693 + 1.1194 + 1.7038 + 0.0339 — 0. 1330 + 1.2966 + 2. 1355 + 1.9935 + 1.2446 + 1.2410 + 0.5962 + 4.2583 + 1.2205 — 0. 1032 + 4.0035 + 4.1494 + 0.4306 + 2.1303 + 4.6968 + 1.5950 + 2.0916 + 0.7494 + 1.9556 + 2.0073 + 1.8570 + 1.6853 + 2.0437 + 1.5322 + 0.3025 + 0.3501 + 1.5253 m. + 0.6247 — 4.4346 — 0.6298 — 0.9638 — 1.32S5 — 0.7958 — 2.8382 — 0.7288 — 2.8103 — 3.7429 — 0.1240 + 3.4650 — 4.8504 — 2.7764 — 2.1645 — 0.1946 — 1.1288 + 0.2260 — 0.2372 \ - 1.2409 — 1.5435 — 2.0144 \ - 1.5225 — 3.9096 — 0.3606 — 6. 1728 — 0.5652 [• — 2. 1407 — 1.0596 — 2. 3514 [ + 0. 8396 — 3. 6331 — 2. 3162 + 1.1637 — 3.4474 + 0.3432 — 2.8618 — 1.2178 — 2.0296 — 0.2685 — 1.1188 — 1.7044 — 0. 0334 + 0.1346 — 1.2976 — 2. 1360 — 1.9920 \ — 1.2412 — 0.5963 — 4.2570 — 1.2222 + 0.1038 — 4.0056 — 4.1502 — 0. 4298 — 2. 1298 — 4.6958 — 1.5945 — 2.0901 — 0. 7479 — 1.9551 — 2. 0076 — 1.8558 — 1.6850 — 2.0435 — 1.5323 — 0. 3031 — 0. 3501 — 1.5236 mm. -3.0 + 1.5 + 2.9 + 1.9 +0.2 +0.7 +0.5 +0.4 -1.0 +2.4 -0.6 +0.3 -0.9 +2.9 +0.2 -2.3 +0.1 -2.9 -0.7 +3.0 -0.6 +0.9 +2.6 +3.1 +0.4 + 1.9 +2.7 + 1.0 + 1.6 +3.3 +2.0 —2.8 —1.6 +4.2 + 1.5 + 1.8 +0.7 +2. 8 —1.6 —1.2 + 1.2 —0.9 —3.2 +2.1 +0.9 -3.0 —3.2 +0.2 —2.7 +3.5 —1.2 +4.1 + 1.5 —1.6 —1.1 —2.0 —1.0 —3.0 —3.0 —1.0 +0.6 —2.5 —0.5 —0.4 +0.2 +1.2 0.0 —3.5 mm. +54.7 +56.2 +59. 1 +61.0 +61.2 +61.9 +62.4 +62.8 +61.8 +64.2 +63.6 +63.9 +63.0 +65.9 +66.1 +63.8 +63.9 +61.0 +60.3 +63.3 +62.7 +63.6 +66.2 +69.3 +69.7 +71.6 +74.3 +75.3 +76.9 +80.2 +82.2 +79.4 +77.8 +82.0 +83.5 +85.3 +86.0 +84.9 +87.7 +86.1 +84.9 +86.1 +85.2 +82.0 +84.1 +85.0 +82.0 +78.8 +79.0 + 76.3 +79.8 + 78.6 +82.7 +84.2 +82.6 +81.5 +79.5 +78.5 +75.5 +72.5 +71.5 +72.1 +69.6 +69.1 +68.7 +68.9 +70.1 +70.1 +66.6 301 302 H s 303 301 Is Js 305 Ks 306 307 L 5 308 309 Ms 310 311 Ns 312 Os Ps Q5 Rs 313 314 Ss 315 316 317 T 5 318 319 Us 320 Vi 321 322 323 324 325 326 327 Ws 328 329 330 331 332 X. 333 334 335 336 337 Ys 338 339 340 341 342 Zs 343 344 345 346 347 A, B, C 1cm. 410. 232 411.451 412. 358 413.574 414. 793 415.600 417.612 418. 827 420. 410 421.595 422. 789 423.827 424. 878 426. 196 427.267 428. 524 429.637 430. 503 431.677 433.021 433. 591 434.568 435.276 436.454 437. 329 438. 592 439. 810 441.025 442.205 443.409 444.508 445. 726 446.641 447. 811 448. 946 450.071 451.199 452.333 453.466 454.597 455. 727 456.857 458.269 459.484 460.700 461. 915 462.967 464.165 464.955 466.233 467.447 468.665 469. 873 471. 091 472.274 473.381 474.600 475. 817 477. 031 478.155 479. 075 480. 210 481.428 482. 646 483.835 484.953 485.314 485.427 486.225 m. 1541. 1478 Do 1536. 7132 Do 1536. 0834 Do 1535.1196 Oct. 25-26 1533. 7911 Do 1532. 9953 Oct. 26-26. 1530. 1571 Do 1529.4283 Do 1526. 6180 Do 1522. 8751 Do 1522. 7511 Oct 28-28 1526. 2161 Do 1521. 3657 Do 1518. 5893 Oct. 28-27 1516. 4248 Oct. 27-27 1516. 2302 Do 1515. 1014 Do 15U.3274 Do 1515. 0902 Do Oct. 30-30 Oct. 27-30 1512.3058 Oct. 30-30 1510. 2914 Nov. 1-1 Do Oct. 30 1504. 8593 Oct. 30-30 1504. 4987 Oct. 30-31 1498.3259 Oct. 31-31 1497. 7607 Do Nov.2-2 Oct. 31-31 1494. 5604 Do 1492. 2090 Do 1493.0486 Oct. 31 Nov. 2 1489. 4155 Nov. 2-2 1487.0993 Do 1488. 2630 Nov.3-3 1484. 8156 Do 1485.1588 Do 1482. 2970 Do 1481. 0792 Do 1479. 0496 Do 1478. 7811 Do 1477. 6623 Do 1475. 9579 Nov. 4-4 1475. 9245 Do 1476.0591 Do 1474. 7615 Do 1472. 6255 Do 1470. 6335 Do Do % 1469. 3923 Nov. 6-6 .' 1468. 7960 Do 1464. 5390 Do 1463. 3168 Do 1463. 4206 Do 1459.4150 Do 1455. 2548 Do 1454. 8350 Do 1452. 7052 Nov. 7-7 Do 1446. 4149 Do 1444.3248 Do 1443. 5769 Do. 1441.6218 Do 1439. 6142 Do 1437. 7584 Nov.8-8 1436. 0734 Do 1434. 0299 Do 1432. 4976 Do 1432. 1945 Do 1431. 8444 Do 1430. 3208 BEOWAWE TO MARMOL, NEV. This section was run between July 18 and October 25, 1912. Precise level No. 7 and rods V and W were used for the entire line. The lengths of these rods at 0° C. as determined by the instrument division of this Survey are as follows: June 17, 1912, rod V, 3.0004 meters, rod W, 3.0004 meters; January 25, 1913, rod V, 2.9999 meters, rod W, 3.0001 meters. 14 U. S. COAST AND GEODETIC SURVEY SPECIAL PUBLICATION NO. 22. These measurements indicate a shortening of the rods. The field measurements confirm this shortening and show it to have taken place between June 26 and August 5. For the remainder of the period of leveling the rods maintained practically a constant length. In the computation the mean length of the rods on July 16, 3.00019 meters or an excess of 0.06 millimeter per meter was used for the leveling done previous to August 5. For the remainder of the season the mean length of the rods given by the office measures of January 25, 1913, 3.0000 meters was used. The index error of rod V was —0.5 millimeter; of rod W, —0.2 millimeter. The new determination of the differences of elevation between the three bench marks recovered at Beowawe showed that they had not been disturbed since their establishment in 1911. The elevations in the following table depend on an elevation of 1431.8444 meters for bench mark B„ at Beowawe as determined by the line from Brigham, Utah, to Beowawe, Nev. Results of leveling, Beowawe to Marmol, Nev.. Date. 1912. July 18-18 Do Do Do Do Do July 18-19 Do Do Do July 19-19 Do Do July 20-19 Do Do Do July 20-20 Do Do Do Do July 22-22 July 20-20 July 22-22 Do Do Do Do July 23-22 Do Do July 23-23 Do Do Do Do July 23-24 Do July 24-24 Do Do Do Do Do July 24-25 Do Do Do Do July 25-25 Do Do Do July 25-20 Do July 26-26 July 27-27 July 26-26 Do Do Do Do From Distance B. M. to in kilo- B. M. meters. As-Bs 0.135 Br-Ce 0.789 Ce-1 0.999 1-2 1.125 1-2 1.125 2-3 1.206 3-4 1.206 4-5 1.290 5-G 6 0.902 G.-6 1.006 6-7 1.103 7-8 1.124 8-9 1.121 9-10 1.163 10-11 1.082 11-12 1.125 12-H 6 1.036 H6-13 1.121 13-14 1.126 14-15 1.104 15-16 1.125 16-17 1.125 16-17 1.125 17-18 1.024 18-19 1.288 19-16 1.185 19-I 6 1.185 Is-20 0.752 20-21 0.984 21-22 0.967 22-23 1.021 23-24 1.020 24-25 1.029 25-26 1.038 25-26 1.038 26-27 1.021 27-J. 1.004 Js-28 1.192 28-29 1.125 29-30 0.777 30-31 1.125 31-32 1.125 32-33 1.124 33-34 1. 124 34-K. 1.123 Kb-35 1.210 35-36 1.124 36-37 1.124 37-38 1.126 38-39 1.126 39-40 0.779 40-41 1.125 41-42 1.086 42-I.» 1.276 1-6-43 0.798 43-44 1.125 44-Ms 1.066 44-Me 1.066 1*5-45 1.073 M6-45 1.073 45-46 1.069 46-47 1.124 47-48 1.123 Difference of elevation. Forward line. m. -0. 3491 -1.5274 -1.8911 -1.3749 -1. 3723 -1.1577 -2.0437 -1.5143 -1.9620 -0.6080 -1.3225 -1.6507 -1.3476 -1.6051 -1. 7709 -1. 2406 -0. 2412 -4. 1594 -2. 2427 -1.6818 -1. 7674 -0. 4100 -0. 4086 -0. 2910 -1.3721 -1.4885 -1. 4875 -1. 6296 +0. 6259 -2. 2144 +2. 9731 + 1.3330 -6. 0975 -3. 6270 -3. 6240 -1.5292 + 1.4908 -3. 9227 +1. 3726 -2. 3373 -0. 2468 +0. 5726 -1.2085 -1.3278 -1. 3321 -1.4185 -1.1976 +0. 3991 -0. 4584 +0. 2049 -0. 5602 -1. 1615 -1.2503 -0. 3158 -0. 4839 -1.9993 +0. 5912 +0. 5867 -1. 1621 -1.1660 -1. 2074 +0.6065 +1.0821 Back- ward line. +0. 3495 +1.5270 +1.8925 +1.3706 +1.3716 +1. 1579 +2.0428 +1.5113 +1.9632 +0. 6079 +1.3219 +1. 6498 +1.3478 +1.6047 +1. 7744 +1. 2405 +0. 2425 +4.1587 +2.2437 + 1.6790 +1.7665 +0. 4141 +0. 4107 +0.2889 +1.3709 +1.4833 +1.4865 +1.6313 -0. 6275 +2. 2148 -2. 9722 -1. 3334 +6. 0973 +3. 6215 +3.6280 +1. 5280 -1.4923 +3. 9208 -1.3696 +2. 3336 +0.2454 -0. 5743 + 1.2094 +1.3256 +1.3322 +1.4176 + 1.1959 -0. 3998 +0. 4617 -0.2087 +0. 5608 +1.1586 +1. 2494 +0. 3155 +0. 4831 +2.0000 -0.5843 \ -0.5878 / + 1.1693 +1.1680 +1. 2084 -0.6073 -1.0844 }- Mean. -0. 3493 -1. 5272 -1. 8918 -1.3724 -1. 1578 -2. 0432 -1. 5128 -1.9626 -0. 6080 -1.3222 -1. 6502 -1.3477 -1.6049 -1. 7726 -1.2406 -0. 2418 -4. 1590 -2. 2432 -1.6804 -1. 7670 0. 4108 -0.2900 -1.3715 -1. 4864 -1. 6304 -1.7 +0.6267 +1.6 -2. 2146 -0.4 +2. 9726 -0.9 + 1.3332 +0.4 -6. 0974 +0.2 -3. 6252 +0.7 -1. 5286 +1.2 + 1.4916 +1.5 -3. 9218 +1.9 +1.3711 -3.0 -2. 3354 +3.7 -0. 2461 +1.4 +0. 5734 +1.7 -1.2090 -0.9 -1.3267 +2.2 -1.3322 -0.1 -1.4180 +0.9 -1. 1968 +1.7 +0. 3994 +0.7 -0.4600 -3.3 +0.2068 +3.8 -0. 5605 -0.6 -1.1600 +2.9 -1. 2498 +0.9 -0. 3156 +0.3 -0. 4835 +0.8 -1.9996 -0.7 +0. 5875 -3.0 -1.1663 -4.6 -1.2079 +0.6069 +1.0832 Discrepancy. Par- tial. -0.4 +0.4 -1.4 +2.5 -0.2 +0.9 +3.0 -1.2 +0.1 +0.6 +0.9 -0.2 +0.4 -3.5 +0.1 -1.3 +0.7 -1.0 +2.8 +0.9 -3.1 +2.1 +1.2 +3.1 -1.0 +0.8 +2.3 Total accu- mu- lated. -0.4 + 0.4 - 1.0 + 1.5 + 1.3 + 2.2 + 5.2 + 4.0 + 4.1 + 4.7 + 5.6 + 5.4 + 5.8 + 2.3 2.4 + 1.1 + 1.8 + 0.8 + 3.6 + 4.5 + 1.4 + 3.5 + 4.7 + 7.8 + 6.1 + 7.7 + 7.3 + 6.4 + 6.8 + 7.0 + 7.7 + 8.9 +10.4 +12.3 + 9.3 +13.0 +14.4 + 16.1 + 15.2 +17.4 +17.3 +18.2 +19.9 +20.6 +17.3 +21.1 +20.5 +23.4 +24.3 +24.6 +25.4 +24.7 +21.7 +17.1 +16.1 +16.9 +19.2 Designa- tion of B. M. A 8 IS.; a i 20 21 22 8 2-1 25 26 27 J« S8 211 30 31 32 33 34 Ei 35 30 37 38 39 40 41 12 (-6 43 44 Me Distance from B.M.B S . km. -0.135 0.000 0.789 1.788 2.913 4.119 5.325 6.615 7.517 8.523 9.626 10.750 11.871 13.034 14.116 15. 241 16. 277 17.398 18.524 19.628 20.753 21. 878 22.902 24.190 25.375 26.127 27. Ill 28.078 29.099 30. 119 31.148 32.186 33.207 34. 211 35. 403 36.528 37.305 38. 430 39. 555 40. 679 41.803 42.926 44. 136 45.260 46. 384 47. 510 48.636 49. 415 50.540 51.626 52.902 53.700 54. 825 55.891 "56.964 58.033 59. 157 60.280 Observed elevation above mean sea level. m. 1432. 1937 1431. 8444 1430.3172 1428. 4254 1427. 0530 1425. 8952 1423. 8520 1422. 3392 1420.3766 1419. 7686 14ia4464 1416. 7962 1415. 4485 1413. 8436 1412. 0710 1410. 8304 1410.5886 1406. 4296 1404. 1864 1402. 5060 1400. 7390 1400.3282 1400.0382 1398. 6667 1397. 1803 1395. 5499 1396.1766 1393. 9620 1396. 9346 1398. 2678 1392.1704 1388. 5452 1387. 0166 1388. 5082 1384. 5864 1385. 9575 1383. 6221 1383. 3760 1383. 9494 1382. 7404 1381.4137 1380. 0815 1378. 6635 1377. 4667 1377. 8661 1377. 4061 1377. 6129 1377. 0524 1375. 8924 1374. 6426 1374. 3270 1373.8435 1371. 8439 1372. 4314 1370. 0572 1370. 6641 1371. 7473 PRECISE LEVELING, BKIGHAM TO SAN FRANCISCO. Results of leveling, Beowawe to Marmol, Nev. — Continued. 15 Date. From B. M. to B. M. Distance in kilo- meters. Difference of elevation. Forward line. Back- ward line. Mean. Discrepancy. Par- tial. Total accu- mu- lated. Designa- tion of B. M. Distance from B.M.Bj. Observed elevation above mean sea level. 1912. July 26-27 July 27-27 Do Do Do Do Do. July 27-29 July 29-29 Do Do Do July 30-29 Do Do July 30-30 Do Do July 30-31 Do July 31-31 Do Do Aug. 1-1 July 31-31 Do July 31-Aug. 1 Aug. 1-1 Do Do Do Do, Do Do Aug. 1-2 Aug. 2-2 Do Do Do Do Do Aug. 2-7 Aug. 7-7 Do Do Do Do Aug. 8-8 Do Do Do Do Do Aug. 8-9 Aug. 9-9 Do Do Do Do Aug. 9-10 Do Aug. 10-10 Do Do Do Do Aug. 12-12 Do Do Do Do Do Aug. 12-13 Aug. 13-13.'.'.'.'.'.'.'.'.'. Aug. 12-13 Aug. 13-13 Aug. 14-13 Do .-.. Aug. 14-14 Do Do Do Do Do Aug. 15-16 Do Do Do Do Do 48-Ns N.-49 49-50 50-51 51-52 52-53 53-54 54-0 6 Ob-55 55-56 56-57 57-58 58-59 59-60 60-P« 60-Ps Pt-61 61-Qe Q.-62 62-63 63-64 64-65 65-R 8 65-R 6 R«-66 66-67 67-68 68-69 69-S6 S^70 70-71 71-72 72-73 73-74 74-75 75-76 76-77 77-T, TV78 78-79 79-80 80-81 81-82 82-U. U«-83 83-84 84-V, V„-85 85-86 86-87 87-88 89-90 90-91 91-92 92-W« Wa-93 93-94 94-X« Xs-95 95-96 96-97 97-98 98-99 99-100 100-Y 6 Y.-101 101-102 102-103 103-104 104-105 105-106 106-107 107-108 107-108 108-Z, Z.-109 109-110 110-111 110-111 111-112 112-113 113-114 114-115 115-A, A7-II6 116-117 117-118 118-119 119-120 120121 0.746 1.117 1.125 1.125 1.104 1.083 1.074 0.592 1.111 1.123 1.083 1.081 1.382 1.082 1.079 1.079 1.171 1.080 1.071 1.126 1.125 1.571 0.593 0.593 1.163 1.225 1.127 1.189 0.742 0.386 1.078 1.067 1.127 1.211 0.623 1.227 1.127 0.369 1.150 1.127 1.126 1.124 1.600 1.149 1.067 1.083 1.152 0.483 1.082 1.104 1.047 1.115 1.124 1.131 0.719 0.845 1.455 1.058 1.033 1.108 1.130 1.061 1.148 1.149 1.276 1.109 1.131 1.169 1.093 1.021 1.023 1.023 1.074 1.149 1.149 1.207 0.922 0.965 1.123 1.123 1.162 1.242 1.264 1.234 1.006 1.050 1.128 1.149 1.074 1.092 1.090 m. +1.2548 -0.2214 +0. 1333 +1. 7874 +1.3936 -0. 4026 -2.2988 -0. 1409 +0.5560 +3. 4737 -3. 4914 -1.4976 +2.3364 +0. 5804 -1. 7192 -1. 7192 -3.9086 -3. 6357 -3.0360 -4. 0346 -0. 7076 -5. 3582 -4.2825 -4.2840 -0. 7238 -1.3032 -0. 9509 -1.4796 -1.2718 +0. 4468 -1.0533 -0. 5510 -0. 7044 -0.6717 -0. 3847 -1.0456 -0. 9627 -1.2920 -0. 5194 -1.0880 -0. 8732 -0. 3924 -0. 2458 -0. 7518 +0. 7525 -0.6881 +0. 4374 -0. 7578 -0. 1218 -3. 2598 +0. 3359 -0.3311 -0.4178 -1.8144 -0. 5895 +0. 4355 +3.9316 +4.5694 +1.4438 -1.3363 -6.0717 -4.9844 -1.7314 -1.3970 -1. 7297 -1.5888 -0. 6166 +4. 9369 -0.3814 +0.8988 -1. 9309 -1.1643 -0. 0976 -2.7148 -2. 7094 -3. 9799 -2. 0116 -0. 4894 +0. 0239 +0.0281 +3. 5673 +4. 4194 +0.9549 -0.9820 -2.3329 +5. 9959 -3.1033 -0. 5484 -1.1178 -3. 5743 -0.6069 m. -1.2530 +0. 2218 -0. 1300 -1. 7847 -1.3923 +0. 4054 +2. 3013 +0.1417 -0. 5562 -3. 4727 +3.4911 +1. 4977 -2.3344 -0. 5790 +1. 7232 +1.7183 +3. 9071 +3. 6342 +3. 0348 +4.0341 +0.7068 +5. 3571 +4.2863 +4.2839 +0.7225 +1.3009 +0. 9519 +1. 4824 +1.2734 -0. 4477 +1.0525 +0. 5490 +0. 7038 +0. 6695 +0. 3829 +1.0437 +0.9618 + 1.2909 +0.5155 +1.0898 +0. 8748 +0.3910 +0. 2440 +0. 7545 -a 7511 +0. 6894 -0. 4390 +0. 7584 +0.1220 +3.2612 -0.3331 +0.3334 +0. 4156 +1.8167 +0.5893 -0. 4361 -3. 9321 -4.5663 -1.4441 +1.3338 +6. 0692 +4.9824 +1. 7324 +1.3981 +1. 7277 +1.5878 +0. 6169 -4.9380 +0.3800 -0. 8974 +1.9275 +1. 1646 +0.0993 +2.7104 +2. 7124 +3. 9795 +2.0120 +0. 4896 -0.0300 -0.0266 -3.5689 -4. 4208 -0. 9580 +0. 9807 +2.3286 -5. 9949 +3. 1041 +0.5488 +1.1193 +3. 5779 +0.6086 m. +1. 2539 -0.2216 +0. 1316 +1.7860 +1.3930 -0. 4040 -2.3000 -0. 1413 +0. 5561 +3. 4732 -3. 4912 -1. 4976 +2.3354 +0. 5797 -1.7200 -3. 9078 -3. 6350 -3. 0354 -4.0344 -0. 7072 -5.3576 -4.2842 -0. 7232 -1.3020 -0. 9514 -1. 4810 -1. 2726 +0. 4472 -1.0529 -0.5500 -0. 7041 -0. 6706 -0. 3Si8 -1.0446 -0.9622 -1.2914 -0. 5174 -1.0889 -0. 8740 -0.3917 -0. 2449 -0. 7532 +0. 7518 -0.6888 +0. 4382 -0. 7581 -0. 1219 -3.2605 +0. 3345 -0.3322 -0. 4167 -1.8156 -0. 5894 +0. 4358 +3.9318 +4.5678 +1.4440 -1.3350 -6. 0704 -4.9834 -1.7319 -1.3976 -1. 7287 -1.5883 -0. 6168 +4.9374 -0. 3807 +0. 8981 -1.9292 -1.1644 -0. 0984 -2. 7118 -3. 9797 -2.0118 -0. 4895 +0. 0272 +3. 5681 +4. 4201 +0. 9564 -0.9814 -2.3308 +5. 9954 -3. 1037 -0. 5486 -1.1186 -3. 5761 -0. 6078 mm. mm. -1.8 +17.4 -0.4 + 17.0 -3.3 + 13.7 -2.7 + 11.0 -1.3 + 9.7 -2.8 + 6.9 -2.5 + 4.4 -0.8 + 3.6 +0.2 + 3.8 -1.0 + 2.8 +0.3 + 3.1 -0.1 + 3.0 -2.0 + 1.0 -1.4 - 0.4 +1.5 +1.5 +1.2 +0.5 +0.8 +1.1 -1.9 +1.3 +2.3 -1.0 -2.8 -1.6 +0.9 +0.8 +2.0 +0.6 +2.2 +1.8 +1.9 +0.9 +1.1 +3.9 -1.8 -1.6 +1.4 +1.8 -2.7 -1.4 -1.3 +1.6 -0.6 -0.2 -1.4 -2.8 -2.3 +2.2 -2.3 +0.2 +0.6 +0.5 -3.1 +0.3 +2.5 +2.5 +2.0 -1.0 -1.1 + 2.0 +1.0 -0.3 + 1.1 + 1.4 -1.4 +3.4 -0.3 -1.7 +0.7 +0.4 -0.4 -0.2 +2.3 +1.6 +1.4 +3.1 +1.3 +4.3 -1.0 -0.8 -0.4 -1.5 -3.6 -1.7 - 2.0 -0.5 + 1.0 + 2.2 + 2.7 + 3.5 + 4.6 + 2.7 + 4.0 + 6.3 + 5.3 + 2.5 + 0.9 + 1.8 + 2.6 + 4.6 + 5.2 + 7.4 + 9.2 +11.1 +12.0 +13.1 +17.0 +15.2 +13.6 +15.0 +16.8 +14.1 +12.7 +11.4 +13.0 +12.4 +12.2 + 10.8 + 8.0 + 5.7 + 7.9 + 5.6 + 5.8 + 6.4 + 6.9 + 3.8 + 4.1 + 6.6 + 9.1 + 11.1 +10.1 + 9.0 + 11.0 +12.0 + 11.7 +12.8 + 14.2 +12.8 +16.2 +15.9 +14.2 +14.9 +15.3 +14.9 +14.7 +17.0 +18.6 +20.0 +23.1 +24.4 +28.7 +27.7 +26.9 +26.5 +25.0 +21.4 +19.7 «1 62 (',3 M H m 67 liS 69 B. 70 71 72 7;; 74 75 7(1 77 To 78 79 SO SI S2 U« 83 S4 V, 85 86 a 90 91 92 W 6 93 94 X, 95 100 Y, 101 102 103 104 105 106 107 108 Z, 109 110 111 112 113 114 115 A, 116 117 118 119 120 121 km. 61.026 62.143 63.268 64. 393 65.497 66.580 67.654 6X246 69. 357 70.480 71.563 72. 644 74.026 75. 108 76. 187 77.358 78.438 79.509 80.635 81.760 83.331 83.924 85.087 86.312 87. 439 88.628 89.370 89. 756 90.834 91.901 93.028 94.239 94.862 96.089 97.216 97.585 98.735 99.862 100.988 102. 112 103. 712 104. 861 105. 928 107.011 108. 163 108.646 109.728 110.832 111.879 112. 994 114.118 115.249 115.968 116. 813 118.268 119.326 120.359 121. 467 122.597 123.658 124.806 125. 955 127. 231 128. 340 129. 471 130. 640 131. 733 132. 754 133. 777 134.800 135. 874 137. 023 138. 230 139. 152 140.117 141.240 142. 402 143. 644 144.908 146.142 147. 148 148.198 149.326 150. 475 151.549 152.641 153.731 m. 1373. 0012 1372. 7796 1372.9112 1374. 6972 1376. 0902 1375. 6862 1373. 3862 1373. 2449 1373. 8010 1377. 2742 1373. 7830 1372. 2854 1374. 6208 1375. 2005 1373. 4805 1369. 5727 1365. 9377 1362. 9023 1358. 8679 1358. 1607 1352. 8031 1348. 5189 1347. 7957 1346. 4937 1345. 5423 1344. 0613 1342. 7887 1343. 2359 1342. 1830 1341.6330 1340. 9289 1340. 2583 1339. 8745 1338. 8299 1337. 8677 1336. 5763 1336. 0589 1334. 9700 1334.0960 1333. 7043 1333. 4594 1332. 7062 1333. 4580 1332. 7692 1383.2074 1332. 4493 1332. 3274 1329. 0669 1329.4014 1329. 0692 1328. 6525 1326. 8369 1326. 2475 1326. 6833 1330. 6151 1335. 1829 1336. 6269 1335. 2919 1329. 2215 1321. Zisi 1322. 5062 1321. 1086 1319. 3799 1317. 7916 1317. 1748 1322. 1122 1321. 7315 1322. 6296 1320. 7004 1319. 5360 1319. 4376 1316. 7258 1312. 7461 1310. 7343 1310. 2448 1310. 2720 1313. 8401 1318. 2602 1319. 2166 1318.2352 1315. 9044 1321. 8998 1318. 7961 1318. 2475 1317. 1289 1313. 5528 1312.9450 16 V. S. COAST AND GEODETIC SUKVEY SPECIAL PUBLICATION NO. 22. Results of leveling, Beowawe to Marmol, Nev. — Continued. Date. Difference of elevation. Discrepancy. Distance Designa- Distance Observed From elevation B. M. to In kilo- Back- Total tion from above B. M. meters. Forward ward Mean. Par- accu- of B. M. B.M.Bo. mean line. line. tial. mu- sea level. lated. TO. TO. TO. TOTO. mm. km. m. 121-122 0.752 -0. 6695 +0. 6715 -0. 6705 -2.0 +17.7 122 154. 483 1312. 2745 122-B 7 1.433 -2. 5391 +2.5414 -2. 5402 -2.3 + 15.4 B, 155. 916 1309. 7343 Bt-123 1.089 +0. 2796 -0.2806 +0.2801 +1.0 +16.4 123 157.005 1310. 0144 123-124 1.022 -1.5328 +1.5338 -1.5333 -1.0 +15.4 124 158. 027 1308. 4811 124-125 1.151 -0. 4518 +0. 4554 -0.4536 -3.6 +11.8 125 159. 178 1308. 0275 125-126 1.111 +0.2099 -0. 2074 +0.2086 -2.5 + 9.3 126 160.289 1308. 2361 126-127 1.093 -0. 7147 +0. 7153 -0. 7150 -0.6 + 8.7 127 161. 382 1307. 5211 127-128 1.093 +0.5837 -0.5868 +0.5852 +3.1 + 11.8 128 162. 475 1308. 1063 128-129 1.023 +4. 1021 -4.1000 +4. 1010 -2.1 + 9.7 129 163. 498 1312. 2073 I29-C7 129-C, 1.127 1.127 +5.4827 +5. 4820 -5.4778 -5. 4803 } +5.4807 -3.4 + 6.3 C7 164. 625 1317.6880 Ct-130 1.074 +2. 8736 -2.8701 +2. 8718 -3.5 + 2.8 130 165. 699 1320.5598 130-131 1.136 -0.6556 +0.6564 -0.6560 -0.8 + 2.0 131 166.835 1319. 9038 131-132 1.077 -2. 1108 +2. 1142 -2. 1125 -3.4 - 1.4 132 167. 912 1317. 7913 132-133 1.123 -4.5630 +4.5653 -4.5642 -2.3 - 3.7 133 169.035 1313.2271 133-134 1.165 -4. 6106 +4. 6101 -4. 6104 +0.5 - 3.2 134 170.200 1308. 6167 134-135 1.128 +2. 5103 -2.5099 +2. 5101 -0.4 - 3.6 135 171.328 1311. 1268 135-D; 1.010 -3.3043 +3.3043 -3.3043 0.0 - 3.6 D, 172.338 1307. 8225 Dj-136 1.049 +3.6160 -3. 6175 +3. 6168 +1.5 - 2.1 136 173.387 1311.4393 136-137 136-137 1.030 1.030 1.109 -2.2695 -2. 2738 -4. 3987 +2.2730 \ -2.2723 -4.4004 -1.4 -3.5 - 3.5 - 7.0 137 138 174.417 175. 526 1309. 1670 137-138 +4.4022 1304.7666 138-139 1.150 -0.4110 +0.4098 -0.4104 + 1.2 - 5.8 139 176. 676 1304.3562 139-140 1.076 +0.0652 -0.0610 +0.0631 -4.2 -10.0 140 177. 752 1304. 4193 140-141 140-141 1.092 1.092 +4. 2895 + 4.2868 -4.2850 -4. 2876 } +4.2872 -1.9 -11.9 141 178.844 1308.7065 141-E, 1.217 + 1.7726 -1.7723 + 1.7724 -0.3 -12.2 E 7 180.061 1310. 4789 Et-142 E,-142 1.151 1.151 -3.8634 -3.8630 +3.8684 +3.8667 \ -3.8654 -4.4 -16.6 142 181. 212 1306. 6135 142-143 1.056 -4.2296 +4.2337 -4.2316 -4.1 -20.7 143 182.268 1302. 3819 143-144 1.092 -4.4124 +4.4128 -4.4126 -0.4 -21.1 144 183.360 1297. 9693 144-145 1.091 -1.1839 +1. 1797 -1. 1818 +4.2 -16.9 145 184. 451 1296. 7875 145-146 1.038 + 1.2921 -1.2919 + 1.2920 -0.2 -17.1 146 185. 489 1298. 0795 146-147 0.985 -2.9454 +2.9465 -2.9460 -1.1 -18.2 147 186. 474 1295. 1335 147-F, 0.528 +0. 7161 -0. 7173 +0. 7167 +1.2 -17.0 F, 187.002 1295.8502 F,-148 1.145 +2.4605 -2. 4601 +2.4603 -0.4 -17.4 148 188. 147 1298. 3105 148-149 1.102 -4.6630 +4. 6616 -4.6623 + 1.4 -16.0 149 189. 249 1293. 6482 149-150 1.163 -3.1999 +3.2005 -3.2002 -0.6 -16.6 150 190. 412 1290.4480 150-151 1.139 -1.4830 + 1.4836 -1.4833 -0.6 -17.2 151 191.551 1288.9647 151-152 1.092 + 1.0622 -1.0608 + 1.0615 -1.4 -18.6 152 192. 643 1290. 0262 152-G7 1.043 -2.8917 +2.8956 -2. 8936 -3.9 -22.5 G7 193.686 1287. 1326 G7-153 1.123 -4.4009 +4.4024 -4.4016 -1.5 -24.0 153 194.809 1282. 7310 153-154 1.093 -2.1886 +2.1906 -2. 1896 -2.0 -26.0 154 195.902 1280. 5414 154-155 1.093 -2.2233 +2.2229 -2. 2231 +0.4 -25.6 155 196.995 1278. 3183 155-156 1.090 -1.5668 + 1.5708 -1.5688 -4.0 -29.6 156 198.085 1276. 7495 156-157 1.057 -0.2252 +0. 2270 -0.2261 -1.8 -31.4 157 199.142 1276. 5234 157-158 1.071 -0. 2439 +0. 2457 -0. 2448 -1.8 -33.2 158 200.213 1276. 2786 158-H 7 0.592 + 1.9917 -1.9923 + 1.9920 +0.6 -32.6 H, 200.805 1278. 2706 Hr-159 1.083 +0. 7198 -0. 7174 +0. 7186 -2.4 -35.0 159 201.888 1278. 9892 159-160 1.092 +2.4203 -2. 4185 +2.4194 -1.8 -36.8 160 202.980 1281.4086 160-161 1.033 +0. 3713 -0. 3714 +0.3714 +0.1 -36.7 161 204.013 1281. 7800 161-162 1.005 +4.0300 -4.0269 +4.0284 -3.1 -39.8 162 205.018 1285.8084 162-163 1.126 +4. 4149 -4. 4129 +4.4139 -2.0 -41.8 163 206.144 1290.2223 163-164 1.061 +3.0460 -3.0441 +3.0450 -1.9 -43.7 164 207.205 1293. 2673 164-165 1.130 -4.5058 +4.5054 -4.5056 +0.4 -43.3 165 208.335 1288.7617 165-166 1.145 -0. 5874 +0. 5892 -0.5883 -1.8 -45.1 166 209.480 1288. 1734 166-167 1.092 -0. 5722 +0.5691 -0. 5706 +3.1 -42.0 167 210. 572 1287.6028 167-168 0.987 + 1.5791 -1.5792 + 1.5792 +0.1 -41.9 168 211.559 1289. 1820 168-Ij 0.864 +0.5005 -0. 4987 +0. 4996 -1.8 -43.7 I 7 212.423 1289. 6816 Ij-169 0.765 -2.6095 +2.6098 -2.6096 -0.3 -44.0 169 213. 188 1287. 0720 169-170 0.913 +0. 9245 -0. 9241 +0. 9243 -0.4 -44.4 170 214. 101 1287.9953 170-171 1.059 +4.1060 -4. 1051 +4.1056 -0.9 -45.3 171 215. 160 1292. 1019 171-172 1.075 + 1.1651 -1. 1675 + 1.1663 +2.4 -42.9 172 216.235 1293. 2682 172-173 1.207 +4.8255 -4. 8235 +4.8245 -2.0 -44.9 173 217.442 1298. 0927 173-174 0.655 + 1.9798 -1.9789 + 1.9794 -0.9 -45.8 174 218. 097 1300. 0721 174-J, 1.191 +3.6638 -3.6607 +3.6622 -3.1 -48.9 J7 219.288 1303. 7343 J7-175 0.592 +3. 5901 -3. 5892 +3.5896 -0.9 -49.8 175 219.880 1307. 3239 175-176 1.210 -2.2699 +2.2695 -2.2697 +0.4 -49.4 176 221.090 1305. 0542 176-177 1.208 -4. 8292 +4.8280 -4.8286 + 1.2 -48.2 177 222. 298 1300. 2256 177-178 1.144 -4. 4991 +4. 4975 -4.4983 + 1.6 -46.6 178 223. 442 1295. 7273 178-K, 0.374 -1.9342 +1.9345 -1.9344 -0.3 -46.9 K 7 223.816 1293. 7929 Kt-179 1.168 +0. 9521 -0. 9510 +0. 9516 -1.1 -48.0 179 224.984 1294. 7445 179-180 1.207 -0. 1227 +0. 1210 -0. 1218 + 1.7 -46.3 180 226.191 1294. 6227 180-L, 1.178 +0.9295 -0. 9287 +0. 9291 -0.8 -47.1 L7 227. 369 1295. 5518 L7-I8I 0.808 +1.4951 -1. 4945 + 1.4948 -0.6 -47.7 181 228. 177 1297.0466 181-182 1.041 +0.6502 -0.6504 +0.6503 +0.2 -47.5 182 229.218 1297.6909 182-M; 0.932 -2.2268 +2.2295 -2.2282 -2.7 -50.2 M 7 230.150 1295. 4687 M7-N7 1.096 -1.6638 +1.6610 -1.6624 +2.8 -47.4 N 7 231.246 1293.8063 Nt-183 0.967 +1.7460 -1.7468 +1.7464 +0.8 -46.6 183 232.213 1295.5527 183-184 1.059 +3.7325 -3. 7316 +3. 7320 -0.9 -47.5 184 233.272 1299.2847 I84-O7 1.192 +0.0600 -0.0607 +0.0604 +0.7 -46.8 O, 234.464 1299. 3451 Ot-185 0.798 -3. 6194 +3. 6214 -3.6204 -2.0 -48.8 185 235.262 1295. 7247 185-186 0.912 -3. 3681 +3.3680 -3.3680 +0.1 -48.7 Ig 236.174 1292. 3567 I86-P7 1.022 -2.8886 +2. 8917 -2. 8902 -3.1 -51.8 237.196 1289.4665 Pt-187 Pt-187 0.111 0.111 -1.5662 -1.5662 + 1.5654 + 1.5658 } -1.5659 +0.6 -51.2 187 237.307 1287.9006 187-188 187-188 1.164 1.164 -4.0052 -4.0002 +3.9971 +3.9985 \ -4.0002 +4.9 -46.3 188 238.471 1283.9004 1912. Aug. 15-16 Aug. 16-16 Do Do Do Do Do Aug. 16-17 Aug. 17-17 Do Aug. 19-19 Aug. 17-17 Do Do Do Aug. 17-19 Aug. 19-19 Do Do Do Aug. 20 Aug. 19-19 Aug. 20-20 Do Aug. 20-21 Aug. 22-22 Aug. 21-21 Do Aug. 22-22 Aug. 21-21 Do Do Aug. 21-22 Aug. 22-22 Do Do Aug. 23-23 Do Do Do Do Aug. 24-24 Do Do Do Do Aug. 24-26 Aug. 26-26 Do Do Do Aug. 26-28 Aug. 28-28 Do Do Do Do Sept. 5-5 Do Do Do Do Do Do Sept. 10-10 Do Do Do Do Do Sept. 10-11 Do Do Do Sept. 11-11 Do Do Do Do Sept. 11-12 Sept. 12-12 Do Do Do Do Sept. 13-13 Sept. 3-12 Sept. 12-13 PRECISE LEVELING, BEIGHAM TO SAN FRANCISCO. Results of leveling, Beowawe to Marmol, Nev. — Continued. 17 Date. From B.M. to B. M. Distance in kilo- meters. Difference ot elevation. Forward line. Back- ward line. Mean. Discrepancy. Par- tial. Total accu- mu- lated. Designa- tion of B. M. Distance from B. M. B«. Observed elevation above mean sea level. Sept. 3 Sept. 12-13. Sept. 12 Sept. 13-13. Sept. 3-12.. Do Do Sept. 7-9... Sept. 13-13. Sept. 7-9... Sept. 9-9... Sept. 7-9... Do Do Do Do Do Do Sept. 9-9... Sept. 7-9... Sept. 9-9... Do Sept. 7-7... Sept. 13-14. Sept. 14-14. Do Do Do Do Do Do Sept. 6-6... Do Do Do Do Sept. 16-16. Do Do Do Do Sept. 6-16. . Sept. 16-16. Sept. 17-17. Sept. 16-17. Sept. 17-17. Do Do Do Do Do Do Do Sept. 17-18. Sept. 18-18. Do Do Do Do Sept. 19-19. Do Do Do Do Sept. 19-20. Sept. 20-20. Do Do Sept. 21-21 . Sept. 20-20. Do Sept. 20-21 . Sept. 21-21 . Do Do Do Do Sept. 23-23. Do Do Do Do Do Sept. 24-24. . Do Sept. 25-25. . Do Do Do 1912. 188-189 188-189 189-190 189-190 190-191 191-192 192-Q, Qt-193 Qt-193 193-194 193-194 194-195 195-196 196-197 197-198 198-Rj R 7 -199 199-200 199-200 200-201 201-202 202-203 203-204 204- Sf St-205 206-206 206- T, T,-U, Ut-207 207-308 208- V 7 V,-209 209-210 210-211 211-212 212-213 213-W7 Wr-214 214-215 215-216 216-217 217-218 218-219 218-219 219- X 7 X 7 -220 220-221 221-222 222-223 223-224 224-225 225- Y, Yt-226 22(3-227 227-228 228-229 229-230 230- Z 7 Zj-231 231-232 232-233 233-234 234-235 235- A, Ad-236 236-237 237-"38 238- r 39 238-239 239-240 240-241 241-242 242-243 243-244 244- B> Bs-245 245-246 246-247 247-248 248-249 249-250 250-251 251-252 252-Cg Ct-253 253-254 254-255 255-256 256-Di 1.081 1.081 1.084 1.084 1.154 1.020 0.445 1.354 1.354 1.025 1.025 1.023 0.914 1.096 1.097 0.502 0.978 1.076 1.076 1.133 0.914 1.153 1.479 0.509 1.176 1.021 1.024 0.915 1.127 1.095 1.038 1.064 1.188 1.173 1.172 1.268 0.532 1.124 1.114 1.020 1.147 1.092 1.094 1.094 0.653 1.134 1.023 1.087 1.022 1.090 1.O90 0.345 1.095 0.546 1.093 1.077 1.093 0.578 1.161 1.084 1.123 1.123 1.082 1.049 0.924 1.122 1.118 1.084 1.084 1.083 0.898 1.099 1.202 1.203 0.847 1.097 1.210 1.117 1.124 1.184 1.082 1.082 0.774 0.690 0.929 1.100 1.101 1.099 1.142 m. -4.6136 -4.6091 (') -4.5524 -3. 7517 -2. 8950 -1.1388 -0.6220 -0.6211 +2.1304 +2.1334 -4.6511 -3. 2336 -4.3969 -4.5496 -2. 6440 -2. 6070 -4.4128 -4.4204 -4.7911 -3. 2653 -4. 8945 -4. 9788 -3.4568 -0. 5375 -2. 0262 -1.2848 -0. 7933 -1.2404 -2. 1071 -1.0383 -1.2286 -2. 4752 -1.6800 -1.5742 +0.5333 -1.8853 -1.6945 -1.7965 +0.0979 -2.3073 -0.7300 -2.5886 -2.5841 -0. 3203 -1.1678 +2.6086 + 1.7589 -0. 3349 -3.3961 +2.4267 + 1.5125 -0. 1651 -0.8048 +4. 1821 -3.0319 -0. 1881 +0.2007 -2.5947 -1.8549 +0.0670 +0. 0613 -0. 4123 +0. 8079 +0. 0357 +0.0606 -2.0199 -3.0219 -3.0239 -1.0357 -1.1427 -0. 7426 -0.4717 -0. 5772 + 1.2909 +3.5358 -0.4054 +0.4064 -1.4319 -1.9903 +1.4090 -2. 1471 -1.4105 +0.0610 -0. 4038 -0. 7773 +1. 1231 +1. 1464 +0. 3237 m. (') +4.6091 +4.5544 +4.5564 +3. 7505 +2.8921 +1. 1387 +0.6150 +0. 6193 -2.1400 -2. 1359 +4.6505 +3.2311 +4. 3988 +4.5461 +2.6444 +2. 6093 +4.4201 +4.4188 +4.7921 +3.2659 +4. 8934 +4. 9789 +3.4584 +0. 5341 +2. 0273 + 1.2869 +0. 7927 + 1.2409 +2. 1058 + 1.0375 + 1.2253 +2.4742 + 1.6787 +1.5742 -0. 5342 + 1.8853 + 1.6951 + 1.7937 -0.0998 +2.3086 +0. 7271 +2.5847 +2. 5871 +0. 3212 + 1.1678 -2. 6073 -1.7590 +0.3356 +3.3943 -2. 4264 -1.5140 +0. 1672 +0. 8039 -4. 1827 +3.0300 +0. 1921 -0. 2070 +2. 5943 + 1.8566 -0.0631 -0. 0614 +0. 4142 -0.8041 -0.0344 -0.0592 +2.0177 +3.0263 +3.0229 + 1.0348 + 1.1438 +0. 7445 +0. 4727 +0. 5776 -1.2888 -3.5384 +0. 4031 -0.4062 + 1.4300 + 1.9906 -1. 4079 +2. 1475 +1. 4097 -0.0636 +0. 4016 +0. 7767 -1. 1232 -1.1441 -0.3234 m. -4. 6102 -4.5539 -3.7511 -2. 8936 -1. 1388 -0. 6194 +2.1350 -4.6508 -3. 2324 -4. 3978 -4. 5478 -2.6442 -2. 6082 -4. 4180 -4. 7916 -3.2656 -4. 8940 -4. 9788 -3.4576 -0. 5358 -2.0268 -1.2858 -0. 7930 -1.2406 -2. 1064 -1.0379 -1.2270 -2. 4747 -1.6794 -1.5742 +0.5338 -1.8853 -1.6948 -1.7951 +0.0988 -2.3080 -0.7286 -2.5862 -0.3208 -1.1678 +2.6080 + 1.7590 -0.3352 -3. 3952 +2. 4266 +1.5132 -0. 1662 -0.8044 +4. 1824 -3. 0310 -0. 1901 +0.2068 -2. 5945 -1.8558 +0.0650 +0.0614 -0.4132 +0.8060 +0.0350 +0.0599 -2.0188 -3.0238 -1.0352 -1.1432 -0. 7436 -0. 4722 -0. 5774 +1.2898 +3. 5371 -0.4042 +0.4063 -1.4310 -1.9904 +1.4084 -2. 1473 -1.4101 +0. 0623 -0. 4027 -0. 7770 +1. 1232 +1. 1452 +0. 3236 mm. +2.3 -3.0 +1.2 +2.9 +0.1 +4.4 +6.1 +0.6 +2.5 -1.9 +3.5 -0.4 -2.3 -2.8 -1.0 -0.6 + 1.1 -0.1 -1.6 +3.4 -1.1 -2.1 +0.6 -0.5 + 1.3 +0.8 +3.3 + 1.0 + 1.3 0.0 +0.9 0.0 -0.6 +2.8 + 1.9 -1.3 +2.9 +0.5 -0.9 0.0 -1.3 +0.1 -0.7 + 1.8 -0.3 + 1.5 -2.1 +0.9 +0.6 + 1.9 -4.0 +0.3 +0.4 -1.7 -3.9 +0.1 -1.9 -3.8 -1.3 -1.4 +2.2 -1.7 +0.9 -1.1 -1.9 -1.0 -0.4 -2.1 +2.6 +2.3 -0.2 + 1.9 -0.3 -1.1 -0.4 +0.8 +2.6 +2.2 +0.6 +0.1 -2.3 -0.3 mm. -44.0 -47.0 -45.8 -42.9 -42.8 -32.3 -31.7 -29.2 -31.1 -27.6 -28.0 -30.3 -33.1 -34.1 -34.7 -33. 6 -33.7 -35.3 -31.9 -33.0 -35.1 -34.5 -35.0 -33.7 -32.9 -29.6 -28.6 -27.3 -27.3 -26.4 -26.4 -27.0 -24.2 -22.3 -23.6 -20.7 -20.2 -21.1 -21.1 -22.4 -22.3 -23.0 -21.2 -21.5 -20.0 -22.1 -21.2 -20.6 -18.7 -22.7 -22.4 -22.0 -23.7 -27.6 -27.5 -29.4 -33.2 -34.5 -35. 9 -33.7 -35.4 -34.5 -35. 6 -37.5 -38.5 -38.9 -41.0 -38.4 -36.1 -36.3 -34.4 -34.7 -35.8 -36.2 -35.4 -32.8 -30.6 -30.0 -29.9 -32.2 -32.5 189 190 191 192 Q7 193 194 195 196 197 198 R 7 199 200 201 202 203 204 87 205 206 T, U, 207 208 V 7 209 210 211 212 213 W 7 214 215 216 217 218 219 X 7 220 221 222 223 224 225 Y, 226 227 228 229 230 Z 7 231 232 233 234 235 A, 236 237 238 239 240 241 242 243 244 B, 245 246 247 248 249 250 251 252 Cs 253 254 255 256 D, km. 239.552 240.636 241.790 242.810 243.255 244.609 245.634 246.657 247. 571 248.667 249.764 250.326 251.304 252.380 253.513 254. 427 255.580 257. 059 257.568 258. 744 259.765 260. 789 261. 704 262. 831 263. 926 264.964 266. 028 267. 216 268. 389 269. 561 270.829 271. 361 272.485 273. 599 274. 619 275. 766 276.858 277.952 278.605 279. 739 280. 762 281.849 282. 871 283.961 285.051 285.396 286.491 287. 037 288.130 289.207 290.300 290.878 292. 039 293.123 294.246 295. 369 296.451 297.500 298. 424 299.546 300.664 301. 748 302.831 303.729 304.828 306. 030 307.233 308.080 309.177 310. 387 311.504 312. 628 313. 812 314. 894 315.976 316. 750 317. 440 318. 369 319. 469 320. 570 321. 669 322.811 1279. 2902 1274. 7363 1270. 9852 1268. 0916 1266. 9528 1266.3334 1268.4684 1263. 8176 1260. 5852 1256. 1874 1251. 6396 1248. 9954 1246.3872 1241.9692 1237. 1776 1233. 9120 1229. 0180 1224. 0392 1220.5816 1220. 0458 1218.0190 1216. 7332 1215. 9402 1214. 6996 1212. 5932 1211.5553 1210.3283 1207.8536 1206. 1742 1204.6000 1205. 1338 1203. 2485 1201. 5537 1199. 7586 1199.8574 1197.5494 1196.8208 1194.2346 1193.9138 1192. 7460 1195.3540 1197. 1130 1196.7778 1193.3826 1195.8092 1197.3224 1197. 1562 11%. 3518 1200.5342 1197.5032 1197.3131 1197.5199 1194.9254 1193.0696 1193. 1346 1193.1960 1192. 7828 1193.5888 1193. 6238 1193.6837 1191.6649 1188.6411 1187.6059 1186.4627 1185. 7191 1185.2469 1184.6695 1185.9593 1189.4964 1189.0922 1189. 4985 1188. 0675 1186.0771 1187.4855 1185.3382 1183. 92S1 1183.9904 1183.5877 1182. 8107 1183.9339 1185. 0791 1185.4027 53167°— 14- Rejected in field. 18 U. S. COAST AND GEODETIC SURVEY SPECIAL PUBLICATION NO. 22. Results of leveling, Beowawe to Marmol, Nev. — Continued. Date. From B. M. to B. M. Distance in kilo- meters. Difference of elevation. Forward line. Back- ward line. Mean. Discrepancy. Par- tial. Total accu- mu- lated. Designa- tion ofB. M. Distance from B.M. Bi. Observed elevation above mean sea level. 1912. Sept. 25-26 Sept. 26-26 Do Do Do Sept. 30-30 Do Do Sept. 30-Oct. 1. Do Do Do Oct. 1-1 Do Do Do Do Oct. 1-2 Do Do Do Do Oct 2-2 Do Do Do Oct. 2-3 Do Do Do Do Oct. 3-3 Do Do Do Do Do Do Oct. 4-4 Do Do Do Do Do Do Do Do Do Oct 5-5 Do Do Oct. 8-8 Do Do Do Do Do Oct 11-11 Do Oct. 11-10 Do Do Oct. 11-12 Do Do Do Do Do Oct. 12-12 Do Do Do Do Oct. 14-14 Do Do Do.. ....... Do Do Oct 15-15 Do Do Oct. 15 Oct 15-15 Do Oct. 16 Oct 16-16 Do Do Do D(r-257 257-258 258-259 259-Es Es-260 260-261 261-262 262-Fs Fg-263 263-264 264-Gs Gs-265 265-266 206 267 267-H 8 Hs-268 268-269 269-270 270-271 271-272 272-273 273-274 274-Is Is-275 275-Ja Js-276 276-277 277-278 278-Ks K»-279 279- Ls Ls-280 280-281 281-282 282-283 283-284 284-Ms Ms-285 285-286 286-N« Ns-287 287-Os On-288 288-Ps P»-289 289-290 290-291 291-Q 8 Q»-292 292-Ra Rs-Ss Ra-Ss S«-293 293-294 294-295 295-296 296-297 297-298 298-Ts Ts-299 299-300 300-Us U«-V 8 VfrW 8 Ws-301 301-302 302-303 303-304 304-Xs Xg-Ys Yb-305 305-306 306-Z 8 Z.-307 307-308 308-309 309-310 310-311 311- Ag A,-312 Aj-312 312-313 313-314 313-314 314-315 315-316 315-316 316-317 317-318 318- B, 1.101 0.982 1.079 0.807 1.044 0.950 1.101 0.862 1.080 1.081 0.509 1.160 0.869 1.083 1.182 1.318 1.165 1.185 1.243 1.207 1.209 1.208 0.997 1.375 1.203 1.098 1.118 1.104 0.487 1.116 0.470 0.830 1.089 1.083 1.0S4 1.084 0.748 1.130 1.087 0.709 1.132 1.115 1.123 0.512 1.137 1.125 1.125 0.895 1.202 1.503 0.211 0.211 1.072 0.843 1.104 1.082 1.023 0.926 1.017 1.071 1.211 1.174 1.151 0.685 1.187 1.120 1.102 1.095 1.221 0.358 0.970 1.169 1.090 1.139 1.144 1.168 1.208 1.207 1.205 0.876 0.876 0.709 1.116 1.116 1.105 1.121 1.121 0.722 1.164 1.193 m. +0.2330 +0.3870 +0. 2606 +2.8492 +3.9296 +0.0110 -4. 2127 -0. 1376 +0.0859 +0. 8930 +0. 2457 +1. 5332 +3. 1794 +4.2149 +0. 1546 +4.6527 +0. 4021 +1.6998 +2. 7519 +0.0693 -0. 1477 +2.9402 -0. 1520 +0. 4836 +4. 5023 +1.6505 -0. 1074 +3. 1041 -0. 4508 -0.3264 -0.3600 +3. 3050 +4.3018 +3. 7991 +3. 5958 +2. 2793 +0. 4864 +3. 3607 +1.6196 -0.0919 -1.3081 +0.0407 +0. 2393 -0. 1431 +5.0789 +4.9205 +3. 7272 +2.6394 +5. 6800 +1.3733 +0. 7100 +0. 7107 -0.0376 +3.7718 -0. 7978 -0.6251 -0. 1263 +0. 1266 +0. 4292 -0. 4275 -0. 0756 +0. 2751 -0.3968 +1.9120 +1.5703 +3.3442 +3.0731 +3.9718 +4.4013 +1.1893 + 1.7324 +2. 1631 +2.9149 +1.6843 +3. 3973 +4.8118 +1.8463 +2. 1971 +1.3108 +0. 7762 +0.7799 +2. 4352 +0. 7S76 +0. 7901 +3.6812 +4. 7191 +4.7214 +2.7134 +4.3666 +5.0811 m. -0. 2316 -0. 3868 -0. 2620 -2.8483 -3. 9290 -0. 0099 + 4.2118 +0. 1401 -0. 0874 -0. 8932 -0. 2436 -1.5339 -3. 1787 -4.2114 -0. 1558 -4. 6512 -0. 4014 -1. 6977 -2. 7521 -0.0713 +0. 1459 -2.9403 +0.1500 -0. 4847 -4.5029 -1.6493 +0.1066 -3. 1045 +0. 4510 +0.3259 +0.3601 -3.3019 -4.2997 -3. 7972 -3. 5995 -2.2807 -0. 4899 -3.3622 -1.6231 +0.0907 +1.3088 -0. 0392 -0. 2390 +0. 1425 -5.0772 -4.9193 -3. 7272 -2.6404 -5.6788 -1.3729 -0. 7106 -0.7107 +0.0364 -3.7738 +0. 7961 +0. 6232 +0. 1256 -0. 1241 -0. 4293 +0. 4274 +0.0733 -0. 2777 +0. 3975 -1.9121 -1.5661 -3. 3459 -3. 0743 -3. 9722 -4.4048 -1.1915 -1.7358 -2. 1628 -2.9131 -1.6850 -3.3967 -4.8144 -1.8474 -2. 1959 -1.3150 -0. 7804 -0. 7802 -2. 4342 (') -0. 7887 -3. 6795 (') -4. 7210 -2. 7133 -4. 3697 -5.0813 m. +0. 2323 +0. 3869 +0. 2613 +2.8488 +3. 9293 +0. 0104 -4.2122 -0. 1388 +0. 0866 +0.8931 +0. 2446 +1.5336 +3. 1790 +4.2132 +0. 1552 +4. 6520 +0. 4018 +1.6988 +2.7520 +0.0703 -0. 1468 +2.9402 -0. 1510 +0. 4842 +4.5026 +1.6499 -0. 1070 +3. 1043 -0.4509 -0. 3262 -0.3600 +3. 3034 +4.3008 +3. 7982 +3.5976 +2.2800 +0. 4882 +3. 3614 +1.6214 -0.0913 -1.3084 +0.0400 +0.2392 -0. 1428 +5.0780 +4.9199 +3. 7272 +2. 6399 +5. 6794 + 1.3731 +0.7105 -0.0370 +3.7728 -0. 7970 -0.6242 -0. 1260 +0. 1254 +0. 4292 -0.4274 -0.0744 +0. 2764 -0. 3972 + 1.9120 + 1.5682 +3. 3450 +3. 0737 +3. 9720 + 1.4030 + 1.1904 +1.7341 +2. 1630 +2.9140 + 1.6S46 +3. 3970 +4.8131 + 1.8468 +2. 1965 + 1.3129 +0.7792 +2.4347 +0. 7888 +3.6804 +4.7206 +2.7134 +4.3682 +5. 0812 mm. -1.4 -0.2 + 1.4 -0.9 -0.6 -1.1 +0.9 -2.5 +1.5 +0.2 -2.1 +0.7 -0.7 -3.5 + 1.2 -1.5 -0.7 -2.1 +0.2 +2.0 +1.8 +0.1 +2.0 +1.1 +0.6 -1.2 +0.8 +0.4 -0.2 +0.5 -0.1 -3.1 -2.1 -1.9 +3.7 + 1.4 +3.5 + 1.5 +3.5 + 1.2 -0.7 -1.5 -0.3 +0.6 -1.7 -1.2 0.0 + 1.0 -1.2 -0.4 +0.2 +1.2 +2.0 + 1.7 + 1.9 +0.7 -2.5 +0.1 +0.1 +2.3 +2.6 -0.7 +0.1 -4.2 +1.7 + 1.2 +0.4 +3.5 +2.2 +3.4 -0.3 -1.8 +0.7 -0.6 +2.6 +1.1 -1.2 +4.2 +2.3 -1.0 -0.1 -1.7 +0.8 -0.1 +3.1 +0.2 mm. -33.9 -34.1 -32.7 -33.6 -34.2 -35.3 -34.4 -36.9 -35.4 -35.2 -37.3 -36.6 -37.3 -40.8 -39.6 -41.1 -41.8 -43.9 -43.7 -41.7 -39.9 -39.8 -37.8 -36.7 -36.1 -37.3 -36.5 -36.1 -36.3 -35.8 -35.9 -39.0 -41.1 -43.0 -39.3 -37.9 -34.4 -32.9 -29.4 -28.2 -28.9 -30.4 -30.7 -30.1 -31.8 -33.0 -33.0 -32.0 -33. 2 -33.6 -33.4 -32.2 -30.2 -28.5 -26.6 -25.9 -28.4 -28.3 -28.2 -25.9 -23.3 -24.0 -23.9 -28.1 -26.4 -25.2 -24.8 -21.3 -19.1 -15.7 -16.0 -17.8 -17.1 -17.7 -15.1 -14.0 -15.2 -11.0 -8.7 - 9.7 -9.8 -11.5 -10.7 -10.8 - 7.7 - 7.5 257 258 259 E 8 260 261 262 Fs 263 264 G 8 265 266 267 H 8 268 269 270 271 272 273 274 In 275 Js 276 277 278 Ks 279 U 280 281 282 283 284 Ms 285 286 N 8 287 8 288 P 8 289 290 291 Q 8 292 R 8 S 8 293 294 295 296 297 298 T 8 299 300 U 8 V, w 8 301 302 303 304 X 8 Y 8 305 306 Z 8 307 308 309 310 311 A, 312 313 314 315 316 317 318 B, km. 323.912 324. 894 325.973 326. 780 327. 824 328. 774 329. 875 330. 737 331. 817 332. 898 333. 407 334. 567 335. 436 336. 519 337. 701 339.019 340. 184 341.369 342.612 543. 819 345.028 346. 236 347. 233 348. 608 349.811 350.909 352.027 353. 131 353. 618 354.734 355. 210 356.040 357. 129 358. 212 359. 296 360. 380 361. 128 362. 258 363. 345 364. 054 365. 186 366. 301 367. 424 367.936 369. 073 370. 198 371. 323 372. 218 373. 420 374.923 375. 134 376. 206 377. 049 378. 153 379. 235 380. 258 381. 184 382. 201 383. 272 384. 483 385.657 386.808 387.493 888. 880 880. 800 390.902 391.997 393. 218 393. 576 394.546 395. 715 396. 805 397.944 399. 088 400. 256 401. 464 402.671 403. 876 404. 752 405. 461 406.577 407. 682 408.803 409. 525 410. 689 411. 882 m. 1185.6350 1186.0219 1186.2832 1189. 1320 1193.0613 1193.0717 1188.8595 1188.7207 1188.8073 1189.7004 1189. 9450 1191. 4786 1194.6576 1198.8708 1199.0260 1203.6780 1204.0798 1205. 7786 1208.5306 1208.6009 1208. 4541 1211.3943 1211.2433 1211.7275 1216. 2301 1217. 8800 1217.7730 1220. 8773 1220. 4264 1220. 1002 1219. 7402 1223. 0436 1227. 3444 1231.1426 1234. 7402 1237.0202 1237. 5084 1210.8698 1242. 4912 1242. 3999 1241.0915 1241. 1315 1241. 3707 1241.2279 1246. 3059 1251.2258 1254.9530 1257.5929 1263. 2723 1264.6454 1265.3559 1265.3189 1269.0917 1268. 2947 1267. 6705 1267. 5445 1267. 6699 1268. 0991 1267.6717 1267. 5973 1267.8737 1267. 4765 1269. 3885 1270. 9567 1274. 3017 1277. 3754 1281.3474 1285. 7504 1286.9408 1288.6749 1290.8379 1293. 7519 1295.4365 1298.833! 1303.6466 1305. 4934 1307. 6899 1309. 0028 1309.7820 1312.2167 1313.0055 1316. 6859 1321. 4065 1324. 1199 1328. 4881 1333.5693 1 Rejected in field. PRECISE LEVELING, BRIGHAM TO SAN FRANCISCO. Results of leveling, Beowawe to Marmol, Nev. — Continued. 19 Date. 1912 Oct. 18-18 Do Oct. 18-17 Do Do Oct. 18-18 Oct. 18-17 Do Oct. 18-19 Do Do Do Do Oct. 19-19 Do Do Do Do Oct. 21-21 Oct. 21 Oct. 21-21 Do Do Oct. 22-23 Oct. 22-22 Do Do Do Do Do Oct. 22-23 Do Do Oct. 24-25 Oct. 23-23 Do Do Do Do Oct. 23-25 Oct. 25-25 Do Do Do Do Do Do From B. M. to B. M. B.-319 319-320 320-321 321- Cj DrEi E»- F9 F»-322 322-323 323-324 324-325 325- G, G»-32U Gj-326 326-327 327-328 328-329 329- H, H.-330 Hj-330 330- I, I.-331 331-332 332-433 333-334 334-335 335-336 336-337 337- J» J»-338 338-339 339-340 339-340 340-341 341-342 342-343 343- K, K.-344 344- L, L»-345 345-346 345-346 346-347 346-347 347- F« E,-F, Distance in kilo- meters. 0. 615 1.179 1.022 0.546 0.957 0.957 0.875 1.428 1.088 1.069 1.040 1. 138 1.428 0.622 0.622 1.042 1.098 1.145 0.378 1.086 1.086 0. 284 1.157 1.123 1.132 1.124 1.123 1. 123 1.100 0.874 1.138 0. 738 1.038 1.038 1.060 1.079 1.079 0.299 1. 083 0.599 1.080 1.018 1.018 1.025 1.025 1.016 0.105 Difference of elevation. Forward line. m. +1. 7493 +0.0859 +0.2040 + 2.0137 +0. 1522 +0. 1484 +1.3681 -0. 1245 -1.0706 +0. 0729 + 1.1721 +3. 1615 +5.0325 +5.8441 +5.8450 +7.8000 +4.4328 +2. 2.538 +1.9823 (') +2.8240 +15.9842 -17. 3154 + 7.0444 + 4.9893 + 4.5129 + 7.3748 + 6.0237 + 7.6743 + 6.6342 + 3.6595 + 4.9243 + 7.6448 J- 7.6428 +16.9772 +12.0908 - 0. 3077 - 1.0305 + 8.7852 + 9.3999 +15.9649 + 7.8586 + 7.8600 + 3.3272 + 3.3297 + 6. 6865 - 0.4397 Back- ward line. m. -1. 7495 -0. 0853 -0. 2059 -2.0442 -0. 1477 -0. 1526 -1.3672 +0. 1280 + 1.0670 -0. 0744 -1. 1727 -3. 1639 -5.0367 -5. 8489 -5.8442 -7. 8022 -4.4332 -2. 2542 -1.9808 -2.8219 -2. 8237 -15.9846 +17.3181 - 7.0418 - 4.9872 - 4.5134 - 7.3725 - 6.0210 - 7.6746 - 6.6354 - 3.6570 - 4.9244 - 7.6394 - 7.6429 -16.9745 -12.0871 + 0.3047 + 1.0325 - 8. 7879 - 9. 4019 -15.9637 - 7.8649 - 7.8596 - 3.3327 - 3.3312 - 6.6867 + 0.4403 Mean. m. +1. 7494 +0.0856 +0.2050 +2.0440 +0.1502 + 1.3676 -0. 1262 -1.0688 +0.0736 + 1.1724 +3. 1627 +5.0346 +5.8456 +2.0 +7.8011 +2.2 +4.4330 +0.4 +2.2540 +0.4 + 1.9816 -1.5 +2.8234 -1.2 + 15.9844 +0.4 -17. 3168 -2.7 + 7.0431 -2.6 + 4.9882 -2.1 + 4.5132 +0.5 + 7.3736 -2.3 + 6.0224 -2.7 + 7.6744 +0.3 + 6.6348 + 1.2 + 3.6582 -2.5 + 4.9244 +0.1 + 7.6425 -2.6 + 16.9758 +12.0890 - 0. 3062 - 1.0315 + 8.7866 + 9.4009 +-15.9643 + 7.8608 + 3.3302 + 6.6866 - 0. 4400 Discrepancy. Par- tial. mm. +0.2 -0.6 +1.9 +0.5 -0.1 -0.9 -3.5 +3.6 + 1.5 +0.6 +2.4 +4.2 -2.7 -3.7 +3.0 -2.0 +2.7 +2.0 -1.2 +2.9 +3.6 +0.2 Total accu- mu- lated. mm. -7.3 -7.9 -6.0 - 5.5 -5.6 - 6.5 -10.0 -6.4 -4.9 -4.3 -1.9 + 2.3 + 4.3 + 6.5 + 6.9 + 7.3 + 5.8 + 4.6 + 5.0 + 2.3 - 0.3 -2.4 - 1.9 -4.2 -6.9 - 6.6 -5.4 - 7.9 - 7.8 -10.4 -13.1 -16.8 -13.8 -15.8 -13.1 -11.1 -12.3 - 9.4 -5.8 - 5.6 Designa- tion of B. M. 319 320 321 C. D, Eg f, 322 323 324 325 G. 326 327 328 329 H„ 330 I> 331 332 333 334 335 336 337 J. 338 339 340 341 342 343 K, 344 U 345 347 F, E, Distance from B.M.B,. km. 412. 497 413. 676 414. 698 415.244 416.201 417.076 418. 504 419. 592 420. 661 421. 701 422. 839 424. 267 424. 889 425.931 427. 029 428. 174 428. 552 129. 638 429. 922 431. 079 432. 203 433.334 434. 458 435. 581 436. 704 437. 804 438.678 439. 816 440.554 441. 592 442. 652 443. 731 444.810 445. 109 446.192 446. 791 447. 871 448.889 449.914 450. 930 451.035 Observed elevation above mean sea level. m. 1335.3187 1335. 4043 1335.6093 1337. 6533 1337.8035 1339.1711 1339.0449 1337.9761 1338.0197 1339. 2221 1342. 3848 1347. 4194 1353.2650 1361. 0661 1365. 4991 1367. 7531 1369. 7347 1372.5581 1388. 5425 1371. 2257 1378.2688 1383. 2570 1387. 7702 1395. 1438 1401. 1662 1408.8406 1415.4754 1419. 1336 1424. 0580 1431.7005 1448.6763 1460. 7653 1460. 4591 1459. 4276 1468.2142 1477. 6151 1493.5794 1501. 4402 1504.7704 1511. 4570 1511. 8970 1 Rejected In field. SAN FRANCISCO, CAL., TO MARMOL, NEV. This section was run between March 7 and July 12, 1912. Precise level No. 10 was used until April 19 and precise level No. 7 for the remainder of the period of leveling. Rods CC and DD were used until July 3, and rods V and W for the remainder of the period of leveling. The lengths of rods CC and DD at 0° C as determined by the instrument division of this Survey are as follows: January 12, 1912, rod CC, 3.0008 meters, rod DD, 3.0012 meters; March 5, 1913, rod CC, 3.0011 meters, rod DD, 3.0015 meters. Both the office and field measurements of the rods show a lengthening. It is assumed that the lengthening was gradual and distributed uniformly over the period between the office measurements. Because of the peculiar profile of this line, which is comparatively level for the first 270 kilometers, rising gradually 2100 meters in the next 170 kilometers and then falling a little in the remaining 56 kilometers, the mean length of the rods, 3.0011 meters, or an excess of 0.37 millimeter per meter, on June 9, which is the mean date of the period of the leveling up the incline, was used in the computations. The index correction of rod CC was —0.3 milli- meter; of rod DD, —0.2 millimeter. The lengths of rods V and W, their index correction, and the mean length used in the computation are given in connection with the line Beowawe to Marmol, Nev. (See p. 13.) The elevations in the table following depend on an elevation of 48.5590 meters for bench mark 635 at San Francisco. This elevation was furnished by the engineer of that city. 20 V. S. COAST AND GEODETIC SURVEY SPECIAL PUBLICATION NO. 22. Results of leveling, San Francisco, Cal., to Marmol, Nev. Date. From B. M. to B. M. Distance In kilo- meters. Difference of elevation. Forward line. Backward line. Mean. Discrepancy. Par- tial. Total accu- mu- lated. Designa- tion of B. M. Distance from B.M. City 635. Observed elevation above mean sea level. 1912. Mar. 8-8.... Mar. 7-7.... Do Mar. 8-8.... Mar. 7-7.... Mar. 7-8.... Mar. 9-9.... Mar.8 Mar. 9-9... Mar. 8-8... Mar. 9-8.... Mar. U-9... Do Do Mar. 11-11.. Mar. 12-12.. Mar. 11-11.. Do Mar. 11-12.. Mar. 12-13.. Mar. 13-13.. Do Do Do Mar. 13-14.. Do Do Do Mar. 14-14.. Do Do Do Mar. 15-16.. Do Do Do Mar. 15-18.. Mar. 18-18.. Mar. 16-18.. Mar. 19-19.. Mar. 16-18.. Mar. 18-18.. Do Do Do Mar. 19-19.. Do Do Do Do Do Mar. 20-20.. Mar. 19-20.. Mar. 20-20.. Do Do Do Do Mar. 21-22.. Do Do Mar. 22-22.. Do Do Do Do Mar. 22-23... Do Do Do Do Do Mar. 23-25... Mar. 25-25.. Do Do Do Do Do Do Mar. 25-27.. Mar. 27-27... Do Do Do Do Do Mar. 28-28... City 635-City 640. City 640-1 City 640-1 City 640- • TSj — 7 1-2 2-3 2-3 0.332 1.579 1.579 1.579 3-City4i8 £T 4-5 5-6 6-7 7-8 7-S 8-W, W.-9 9-10 10-11 11-X, X«-12 12-13 13-14 14-Y. Y r 15 15-16 16-Z 6 Zu-17 17-A, At-Bt Bt-18 18-19 19-C, Cr-20 20-21 21-Dr Dt-22 22-23 22-23 23-E ; 23-E7 Er-24 24-25 25-F7 Ft-26 26-27 27-28 28-29 29-Gt Gt-30 Gt-30 30-H, 30-H, Ht-I, Ir-31 3I-J7 J7-32 32-33 33-34 34-35 35-36 36-K 7 Kt-37 Kt-37 37-38 38-39 39-L7 39-L7 Lt-40 40-41 4I-M7 Mr-42 42-43 43-44 44-45 45-N7 Nt-46 46-47 47-48 48-0 7 0,-P, Pt-49 49-50 50-51 51-52 52-Q, 52-Q, TOT 1.123 0.472 0.472 +10.8331 1+10.2259 +10.2378 +10.2342 -16. am + 14.2231 +14.2352 TO. -10.8347 -10.2344 -10.2305 -10.2324 + 7.0375 0.279 + A.873J O.OJO • 111. 9ii79 II. 2226 -14.2380 - 7.0531 - 7.0354 TO. +10.8339 +10.2342 mm. + 1.6 -3.6 + 1.6 - 2.0 City 635 City 640 1 km. 0.000 0.332 1.911 -16.96J3 - I TS City 586 "OTT 0.996 1.057 1.112 0.980 0.980 1.283 1.278 1.201 1.214 1.433 0.900 1.209 1.208 1.215 1.209 1.196 1.911 0.828 1.324 0.608 1.183 1.818 0.640 1.212 1.047 0.642 0.133 1.200 1.200 0.779 0.779 1.042 1.210 1.186 1.229 1.149 1.078 1.103 1.000 1.198 1.198 0.209 0.209 0.737 1.231 1.303 1.203 1.184 1.207 1.176 0.980 1.215 1.231 1.231 1.010 1.210 0.922 0.922 0.893 1.209 1.217 1.161 0.886 1.282 1.208 1.215 1.495 1.238 0.935 0.371 0.513 0.473 1.126 1.201 1.072 0.814 0.814 - 8. 1)111 -10.9755 -11.0882 -11.7090 -.9.4753 - 9.4722 -11. 8540 -12.4919 - 5.6283 - 0.2409 - 0. 3837 - 3.5610 - 1.5980 + 1.9631 + 0.6689 - 2.6883 + 0.3098 + 6.0721 - 0.8345 - 0. 6006 + 0.4744 - 5.0244 + 0.0874 + 3.5754 - 3. 7290 + 8.4523 - 1.1010 + 0. 1657 - 5.5414 - 5.5427 + 2.6145 + 2. 6131 - 2.5497 + 1.4465 - 2.8658 + 1.3710 + 4.1720 + 3.9389 + 4.0046 + 4.1683 - 0.3221 - 0. 3260 + 1.2058 + 1.2049 - 3.4879 - 5. 6291 - 3.2822 - 0.6039 + 2.3001 + 1.5911 + 3.4509 + 3.2123 + 3.6975 + 6.4901 + 6.4905 + 0.0238 + 0.2760 - 0. 6402 - 0.6400 - 2.6563 - 4.3090 - 2.4186 - 2.7803 + 0.7627 + 0.2308 + 1.9892 + 2.3723 + 1.7125 + 1.9634 + 0.5922 + 0.2058 + 2.4294 - 1.9530 - 5.1876 - 1.6339 - 1.6914 + 1.2002 + 1.1962 - 3.8719 + S.MSV +10.9753 + 11.0890 +11.7115 + 9.4792 + 9.4737 +11.8545 +12.4915 + 5.6255 + 0.2419 + 0.3816 + 3.5586 + 1.5953 - 1.9651 - 0.6584 + 2.6898 - 0.3090 - 6.0676 + 0.8313 + 0.5998 - 0. 4736 + 5.0237 - 0.0883 - 3.5729 + 3. 7251 - 8.4498 + 1.1005 - 0.1644 + 5.5469 + 5.5405 - 2.6089 - 2.6151 + 2.5496 - 1.4445 + 2.8667 - 1.3709 - 4.1722 - 3.9392 - 4.0039 - 4.1672 + 0.3272 + 0.3234 - 1.2053 - 1.2048 + 3.4866 + 5.6313 + 3.2837 + 0.6049 - 2.3008 - 1.5894 - 3.4484 - 3.2102 - 3.6940 - 6.4849 - 6.4881 - 0.0227 - 0.2740 + 0.6349 + 0.6382 + 2.6521 + 4.3081 + 2.4191 + 2.7807 - 0.7626 - 0.2353 - 1.9911 - 2.3735 - 1.7116 - 1.9618 - 0.5936 - 0.2061 - 2.4295 + 1.9520 + 5.1885 + 1.6358 + 1.6911 - 1.1952 - 1.1974 + 14.2366 +2.8 + 0.8 3.034 + 7.0354 T 3. 8726 1 - 8. 9124 -10.9754 -11.0886 -11. 7102 - 9.4751 -11.8542 -12.4917 - 5.6269 - 0.2414 - 0.3826 - 3.5598 - 1.5966 + 1.9641 + 0.6686 - 2.6890 + 0.3094 + 6.0698 - 0.8329 - 0. 6002 + 0.4740 - 5.0240 + 0.0878 + 3.5742 - 3.7270 + 8.4510 - 1.1008 + 0.1550 - 5.5428 + 2.6129 - 2.5496 + 1.4455 - 2.8662 + 1.3710 + 4.1721 + 3.9390 + 4.0042 + 4.1678 ■ - 0.3247 ■ + 1.2052 - 3.4872 - 5.6302 - 3.2830 - 0.6044 + 2.3004 + 1.5902 + 3.4496 + 3.2112 + 3.6958 ■ + 6.4884 + 0.0232 + 0.2750 - 0.6384 - 2.6542 - 4.3086 - 2.4188 - 2.7805 + 0.7626 + 0.2330 + 1.9902 + 2.3729 + 1.7120 + 1.9626 + 0.5929 + 0.2060 + 2.4294 - 1.9525 - 5. 1880 - 1.6348 - 1.6912 + 1.1972 -2.1 1.3 -1.4 +0.2 -0.8 -2.5 -2.6 -0.5 +0.4 +2.8 -1.0 +2.1 +2.4 +2.7 +2.0 -0.5 -1.5 -0.8 -4.5 +3.2 +0.8 -0.8 +0.7 +0.9 -2.5 +3.9 -2.5 +0.5 -1.3 -1.7 -1.8 +0.1 -2.0 -0.9 -0.1 +0.2 +0.3 -0.7 -1.1 -1.3 -0.4 +1.3 -2.2 -1.5 -1.0 +0.7 -1.7 -2.5 -2.1 -3.5 -3.8 -1.1 -2.0 +3.5 +4.2 +0.9 -0.5 -0.4 -0.1 +4.5 +1.9 +1.2 -0.9 -1.6 +1.4 +0.3 +0.1 + 1.0 -0.9 -1.9 +0.3 -TT7 - 3.7 -4.5 - 7.0 - 9.6 -10.1 - 9.7 - 6.9 - 7.9 - 5.8 - 3.4 - 0.7 + 1.3 + 0.8 - 0.7 - 1.5 - 6.0 - 2.8 - 2.0 - 2.8 - 2.1 -1.2 -3.7 + 0.2 - 2.3 - 1.8 - 3.1 - 4.8 - 6.6 - 6.5 - 8.5 - 9.4 -9.5 - 9.3 - 9.0 - 9.7 -10.8 -12.1 -12.5 -11.2 -13.4 -14.9 -15.9 -15.2 -16.9 -19.4 -21.5 -25.0 -29.9 -31.9 -28.4 -24.2 -23.3 -23.8 -24.2 -24.3 -19.8 -17.9 -16.7 -17.6 -19.2 -17.8 -17.5 -17.4 -16.4 -17.3 -19.2 -18.9 Mtjilk T7! -1.9 -20.8 W 8 9 10 11 X, 12 13 14 r, 1.5 10 z, 17 A 7 Bi is 19 a 20 •21 Di 22 23 24 25 F, 2l> 27 M a G, 3(1 <* 4.456 5.452 6.509 , 7.621 8.601 9.884 11.162 12.363 13. 577 15.010 15.910 17.119 18. 327 19.542 20. 751 21.947 23.858 24.686 26.010 26. 618 27. 801 29. 619 30.259 31.471 32.518 33.160 33.293 34.493 35.272 36.314 37. 524 38. 710 39. 939 41.088 42.166 43.269 44.269 45.467 H; 45. 676 l7 46. 413 n 47.644 j. 48. 947 13 50.150 n 51.334 34 52.541 35 53.717 n 54.697 K; 55. 912 37 57.143 a 58.153 39 59.363 L? 60.285 40 61.178 41 62.387 If, 63.504 42 64.765 43 65.651 44 66.933 45 68.141 N, 69.356 4li 70.851 ■17 72.089 4S 73.024 <>, 73.395 l J 7 73.908 49 74.381 M 75. 507 51 76. 708 52 77.780 78.594 m. 48. 5590 59. 3929 69. 6271 r A&m 83.8637 90.9001 TTtTSTI 81.9877 71.0123 59. 9237 48. 2135 38. 7384 26.8842 14. 3925 8.7656 8.5242 8. 1416 4.5818 2.9852 4.9493 5. 6179 2.9289 3.2383 9.3081 8. 4752 7. 8750 8.3490 3.3250 3.4128 6.9870 3.2600 11. 7110 10. 6102 10. 7752 5.2324 7.8453 5.2957 6. 7412 3.8750 5.2460 9. 4181 13. 3571 17. 3613 21.5291 21.2044 22.4096 18.9224 13.2922 10.0092 9.4048 11.7052 13.2954 16. 7450 19. 9562 23.6520 30. 1404 30. 1636 30.4386 29.8002 27. 1450 22.8374 20. 4186 17.6381 18. 4007 18. 6337 20. 6239 22.9968 24. 7088 26. 6714 27.2643 27. 4703 29.8997 27. 9472 22.7592 21. 1244 19.4332 20.6304 1 Rejected. •Rejected, T. B. M. was disturbed. PRECISE LEVELING, BBIGHAM XO SAN FKANCISCO. Results of leveling, San Francisco, Cal., to Marmol, Nev. — Continued. 21 From B. M. to B. M. Distance in kilo- meters. Difference of elevation. Discrepancy. Designa- tion of B. M. Distance from B. M. City 635. Observed Date. Forward line. Backward line. Mean. Par- tial. Total accu- mu- lated. elevation above mean sea level. 1912. Mar. 27-27 Qr-53 53-54 54-55 55-56 56-57 57-Rj Rr-58 58-59 58-59 59-S, 8r-60 60-61 61-T, Tt-62 62-63 63-U, TJ,-64 64-V, Vr-65 65-66 66-67 67-W, Wr-X, X7-68 68-69 69-Y, Yr-Z, Zt-70 70-71 71-72 72-73 73-A, A>-74 A.-74 74-75 75-76 76-77 77-B, B«-78 78-79 79-Cs Cs-80 80-81 81-D, Ds-82 82-83 83-84 84-85 84-85 85-E 8 E»-86 86-F 8 Fk-87 87-88 88-0$ Gs-89 89-90 90-91 91-H. Hs-92 92-T„ Is-93 93-94 94-J, J.-K, K,-95 95-96 96-97 97-L 8 97-L 8 L.-98 Lt-98 98-99 99- Ms Mi-lOO 100-101 101-N 8 N«-102 Ns-102 102-103 103-O 8 Ob-104 104-105 105-106 106-107 107-108 107-108 108-109 108-109 109-110 110-P 8 1.173 1.210 1.209 1.206 1.208 0.369 1.210 1.207 1.207 0.544 1.114 1.185 0.707 1.166 1.131 0.418 1.253 1.739 1.188 1.207 1.126 1.233 0.802 0.564 0.976 1.044 1.374 1.159 1.040 1.264 0.729 0.920 0.886 0.886 1.132 1.078 1.196 1.230 1.456 1.123 1.123 1.113 1.274 0. 313 1.172 1.124 1.127 1.187 1.187 1.223 0.657 1.245 1.143 1.108 1.242 1.100 1.150 1.219 1.330 1.118 1.391 1.469 0.592 0.211 0.705 1.028 1.121 1.202 0.554 0.554 1.039 1.039 1.194 1.096 1.001 1.081 0.296 1.043 1.043 1.019 0.457 1.098 1.023 1.041 1.013 1.077 1.077 1.150 1.150 1.021 0.633 TO. — 3. 6132 — 4. 0062 — 2.5567 — 3.6482 — 2. 5831 + 1.0033 — 1.2081 + 0.9164 + 0.9145 — 0. 1319 + 4.1285 + 4.5842 — 0. 6871 + 1.6192 — 3. 2012 — 1.4416 + 0.4049 + 11.1458 — 4. 3567 + 0.9260 + 5.0201 + 2.7526 + 0.7394 + 4.1073 + 3.6692 + 3.7097 + 13. 1407 + 7.0093 + 1.1614 + 4.8815 + 2.5542 + 2.0S93 + 7.4457 + 7.4462 + 2.8282 + 3.9885 + 4.0809 + 5.1480 + 9.6497 + 1.5385 — 0.9056 + 8.2545 — 0. 1424 + 1.4208 + 1.5674 + 2. 2307 + 3.9372 + 8.1550 + 8. 1490 + 12.4868 — 0. 6095 + 8.8431 + 6.8521 + 6.4809 + 1.7316 + 3.3844 + 3. 1742 + 10.5388 + 14.4720 + 9.4587 + 13.5292 + 3.6803 + 2.8298 + 0. 7348 — 6.2892 —12. 0916 —10. 8607 —11. 2386 — 5.0093 — 5.0104 — 9. 4438 — 9. 4425 —10. 6230 — 9. 5605 —10. 4644 — 8. 0848 — 2. 9304 —10. 0936 —10. 0898 — 7.5155 — 4. 1878 —10. 9322 — 9. 6601 — 8. 7558 — 8. 7952 — 9. 2931 — 9.2928 —11.3777 —11.3757 —10. 1971 — 6.7351 TO. + 3.6139 + 4.0051 + 2.5592 + 3.6491 + 2.5839 — 1.0021 + 1.2088 — 0.9119 — 0. 9134 + 0. 1319 — 4. 1300 — 4. 5817 + 0.6890 — 1. 6206 + 3.2034 + 1.4433 — 0.4064 —11. 1411 + 4.3586 — 0.9248 — 5.0224 — 2.7505 — 0.7405 — 4.1071 — 3. 6692 — 3.7090 + 13.1419 — 7. 0078 — 1. 1576 — 4.8806 — 2. 5567 — 2. 0892 — 7.4385 — 7. 4444 — 2. 8267 — 3. 9881 — 4.0800 — 5. 1486 — 9. 6516 — 1. 5387 + 0.9041 — 8.2538 + 0.1455 — 1.4209 — 1.5690 — 2.2336 — 3. 9336 — 8. 1498 — 8. 1486 —12. 4876 + 0.6084 — 8.8405 — 6.8504 — 6. 4794 — 1.7316 — 3. 3828 — 3. 1759 —10. 5341 —14. 4677 — 9. 4618 —13. 5267 — 3. 6782 — 2. 8315 — 0. 7340 + 6.2891 +12.0928 +10. 8617 +11.2380 + 5.0051 + 5.0071 + 9.4447 m. — 3.6136 — 4.0056 — 2.5580 — 3.6486 — 2.5835 + 1.0027 — 1.2084 \ + 0.9140 — 0. 1319 + 4.1292 + 4.5830 — 0.6880 + 1.6199 — 3.2023 — 1. 4424 + 0.4056 + 11.1434 — 4. 3576 + 0.9254 + 5.0212 + 2.7516 + 0.7400 + 4.1072 + 3.6692 + 3.7094 + 13.1413 + 7.0086 + 1.1595 + 4.8810. + 2.5554 + 2.0892 \ + 7.4437 + 2.8274 + 3.9883 + 4.0804 + 5. 1483 + 9.6500 + 1.5386 — 0.9054 + 8.2542 — 0. 1440 + 1.4208 + 1.5682 + 2.2322 + 3.9354 j. + 8.1506 + 12.4872 — 0.6090 + 8.8418 + 6.8512 + 6.4802 + 1.7316 + 3.3836 + 3. 1750 + 10.5364 + 14.4698 + 9.4602 +13. 5280 + 3.6792 + 2.8305 + 0.7344 — 6. 2892 —12.0922 —10. 8612 —11.2383 } — 5.0080 1 — 9.4440 —10. 6248 — 9. 5588 —10. 4654 — 8.0848 — 2. 9300 } —10. 0907 — 7. 5143 — 4. 1873 —10. 9322 — 9.6603 — 8. 7566 — 8. 7946 \ — 9. 2922 } —11.3742 —10. 1957 — 6.7359 TOTO. -0.7 + 1.1 -2.5 -0.9 -0.8 -1.2 -0.7 —2.8 0.0 + 1.5 —2.5 —1.9 +1.4 —2.2 —1.7 +1.5 —4.7 —1.9 —1.2 +2.3 —2.1 + 1.1 —0.2 0.0 —0.7 + 1.2 —1.5 —3.8 —0.9 +2.5 —0.1 —4.6 —1.5 —0.4 -0.9 +0.6 +1.9 +0.2 +2.5 —0.7 —3.1 +0.1 +1.6 +2.9 —3.6 —2.8 +0.8 + 1.1 —2.6 —1.7 —1.5 0.0 —1.6 +1.7 —4.7 —1.3 +3.1 —2.5 —2.1 +2.0 —0.8 +0.1 —1.2 —1.0 +0.6 +3.7 —1.5 —3.7 +3.3 —1.9 0.0 +0.7 +2.0 +2.4 +1.0 -O.l —0.4 —1.6 +1.1 +1.6 +5.1 +2.8 —1.6 mm. -21.5 -20.4 -22.9 -23.8 -24.6 -25.8 -26.5 —29.3 —29.3 —27.8 —30.3 —32.2 —30.8 —33.0 —34.7 —33.2 —37.9 —39.8 —41.0 —38.7 —10.8 —39.7 —39.9 —39.9 —40.6 —39.4 —40.9 -44.7 —45.6 -43.1 —43.2 —47.8 —49.3 —49.7 —50. 6 —50.0 —48.1 —47.9 —45.4 —46.1 —49.2 —49.1 —47.5 —44.6 —48.2 —51.0 —50.2 —49.1 —51.7 —53.4 —54.9 —54.9 -■56.5 —54.8 —59.5 —63.8 —60.7 —63.2 —65.3 —63.3 —64.1 —64.0 —65.2 —66.2 —65.6 —01.9 —63.4 -07.1 —63.8 —05.7 —65.7 —65.0 —63.0 —60.6 —59.6 —59.7 —60.1 —61.7 —60.6 -59.0 —53.9 —51.1 —52.7 53 54 55 56 57 R7 58 59 S, 60 61 T, 62 63 U, 64 V, 65 66 67 W, Xt 68 69 Y 7 z 7 70 71 72 73 A 8 74 75 76 77 B, 78 79 C 8 80 81 D 8 82 83 84 85 E„ 86 F 8 87 88 G. 89 90 91 Hs 92 I. 93 94 Js K„ 95 96 97 U 98 99 Ma 100 101 N. 102 103 o 8 104 105 106 107 108 109 110 P, km. 79.767 80. 977 82.186 83.392 84. 600 84. 969 86. 179 87.386 87. 930 89.044 90.229 90.936 92.102 93.233 93.651 94.904 96. 643 97.831 99.038 100. 164 101. 397 102.199 102.763 103. 739 104.783 106. 157 107. 316 108. 356 109.620 110. 349 111. 269 112,155 113. 287 114. 365 115. 561 116. 791 118. 247 119. 370 120. 493 121.606 122.880 123. 192 124.365 125.489 126. 616 127.803 129.026 129.683 130. 928 132. 071 133. 179 134. 421 135. 521 136. 671 137. 890 139.220 140.338 141. 729 143. 198 143. 790 144.001 144.706 145. 734 146.855 148. 057 148.611 149.650 150. 844 151. 940 152. 941 154.022 154.318 155.361 156.380 156.837 157. 935 158. 958 159.999 161. 012 162.089 163.239 164.260 164.893 m. 17. 0168 Do 13.0112 Mar. 28-29 10. 4^2 Do 6. 8046 Mar. 28-28 4.2211 Do 5. 2238 Do 4. 0154 Do 4.9294 Do...'. Do 4. 7975 Do 8.9267 Mar 29-29 13.5097 Do 12. 8217 Do 14. 4416 Do 11.2393 Do 9.7969 Do 10.2025 Mar 30 30 21.3459 Do 16.9883 Do 17. 9137 Do 22. 9349 Do 25.6865 26.4265 30. 5337 Do 34.2029 Do 37. 9123 Do 51.0536 Do 58.0622 Do 59. 2217 Do 64. 1027 Apr. 3-4 66.6581 Apr. 4-4 68.7473 Do 76. 1910 Do Do 79.0184 Do 83.0067 Do 87. 0871 Do 92.2354 101. 8860 p bo.::::::::::::::::: 103. 4246 Do 102. 5192 Do 110. 7734 Do 110. 6294 Apr. 6-6 112.0502 Do 113.6184 Do 115.8506 Do 119. 7860 Do 127. 9366 Apr. 8-8 140. 4238 Apr. 8-8 139. 8148 Do 148. 6566 Do 155. 5078 Do 161. 9880 163. 7196 167. 1032 170. 2782 Do 180. 8146 Apr. 9-12 195.2844 Do 204.7446 Di 218. 2726 Do 221. 9518 Do 224. 7823 Apr. 12-12 225. 5107 Do 219. 2275 Do 207.1353 Do 196. 2741 Apr. 13-13 185. 0358 Do 180.0278 Do Do 170.5838 Apr. 15 Apr. 13-13 +10.6267 + 9.5572 + 10.4663 + 8.0848 + 2.9297 + 10.0888 + 10.0900 + 7.5131 + 4.1868 +10.9323 + 9.6605 + 8.7574 + 8.7941 + 9.2880 + 9.2947 + 11.3723 +11.3710 +10.1943 + 6.7367 159. 9590 Apr. 15-15 150. 4002 Do 139. 9348 Do 131.8500 Do 128.9200 Do 118.8293 Do Do 111.3150 Do 107. 1277 Apr. 16-16 96.1955 Do 86.5352 Do 77. 7786 Do 68.9840 Do Apr. 17-22 Apr. 16-16 Apr. 17-22 48. 3176 Apr. 16-16 38. 1219 Apr. 22-20 31.3860 22 U. S. COAST AND GEODETIC SURVEY SPECIAL PUBLICATION NO. 22. Results of leveling, San Francisco, Cal., to Marmol, Nev. — Continued. From B. M. to B. M. Distance in kilo- meters. Difference of elevation. Discrepancy. Designa- tion of B. M. Distance from B. M. City 635. Observed Date. Forward line. Backward line. Mean. Par- tial. Total accu- mu- lated. elevation above mean sea level. 1912. Apr. 22-20 Pu-111 111-112 112-113 113-Qs 113-Q, Qs-Rs Rn-Sg Ss-114 114-115 115-116 115-116 116-T, Ts-Us TJb-117 117-118 118-119 119-120 120-V, Vs-121 121-122 122-123 123-124 124-W 8 Wb-Xs X»-125 125-126 125-127 127-Y 8 Ys-Zs Ys-Zs Zs-128 128-129 129- A, A„-B 9 Bj-Ca C-130 130-131 131-132 132-133 133- D» Dj-E s Ea-134 > 134-135 135-F, Gb-136 136-137 137-138 138- H 9 H,-I 9 H,-I„ Id-139 139-140 140-141 1.237 1.023 1.092 0.947 0.947 0.226 0.530 1.061 1.138 1.372 1.372 1.076 1.665 1.262 0.453 1.137 1.076 1.090 0.917 1.086 1.165 1.019 1.161 0.057 0.424 1.120 1.246 1.206 0.796 0.796 1.205 1.497 0.998 0.402 1.140 0.720 1.182 1.208 0.761 1.210 0.098 1.024 1.144 1.357 0.936 1.203 1.209 1.106 0.325 1.326 1.326 1.245 1.209 1.127 771. —10. 1176 — 0. 7618 + 0.2179 — 2. 6977 — 2.6965 + 0.3136 — 1. 8366 — 1. 7307 — 1. 4898 — 2. 1728 — 2. 1779 — 4. 2565 — 0. 6066 + 0.3594 + 0.0233 + 0.0150 + 0.2071 + 1.4484 — 0. 9303 — 0.4040 + 0.3224 — 0.2339 — 0.8437 + 0.6757 — 0. 8107 + 0.0500 + 0.3931 — 0.0049 + 1.0498 + 1.0515 — 0. 6251 — 0. 3924 — 0. 5369 — 1. 1243 + 1.0349 + 0. 1614 + 1.3602 — 0. 3486 + 0.2381 — 0. 7269 + 1.0809 — 0.5442 — 0. 0168 — 0.1506 + 2.2894 — 0. 5212 + 0.7608 + 0.7170 — 0. 7757 + 1.4461 + 1.4433 + 0. 7568 + 0.4095 + 0.6241 777. + 10.1165 + 0.7504 — 0. 2197 + 2.6937 + 2.0952 — 0. 3150 + 1.8372 + 1.7310 + 1.4871 + 2.1777 + 2. 1801 + 4.2593 + 0.6035 — 0. 3578 — 0. 0220 — 0. 0148 — 0.2001 — 1.4443 + 0.9397 + 0.4075 — 0.3209 + 0.2348 + 0.8451 — 0. 0750 + 0.8110 — 0.0529 — 0.3904 + 0.0039 — 1.0541 — 1. 0498 + 0.6215 + 0.3892 + 0.5335 + 1.1239 — 1.0325 — 0. 1611 — 1. 3579 + 0.3467 — 0. 2365 + 0. 7292 — 1. 0878 + 0.6440 + 0.0191 + 0. 1501 — 2.2881 + 0.5190 — 0. 7597 — 0. 7144 + 0.7748 — 1.4468 — 1. 4487 — 0. 7529 — 0. 4081 — 0. 0210 m. —10. 1170 — 0. 7611 + 0.2188 \ — 2.6958 + 0.3143 — 1.8369 — 1. 7308 — 1.4884 } — 2. 1772 — 4. 2579 — 0.6050 + 0.3586 + 0.0230 + 0.0149 + 0.2066 + 1.4464 — 0. 9380 — 0.4058 + 0.3216 — 0.2344 — 0.8444 + 0.6754 — 0. 8108 + 0.0544 + 0.3918 — 0.0044 | + 1.0513 — 0. 0233 — 0. 3908 — 0. 5352 — 1.1241 + 1.0337 + 0. 1012 + 1.3590 — 0. 3476 + 0. 2373 — 0.7280 + 1.0874 — 0.6441 — 0. 0180 — 0.1504 + 2.2888 — 0. 5201 + 0.7602 + 0.7157 — 0.7752 } + 1.4462 + 0. 7548 + 0.4088 + 0.0220 777 771. + 1.1 + 1.4 +1.8 +2.7 +1-4 —0.6 —0.3 +2.7 -3.5 —2.8 +3.1 —1.6 —0.7 —0.2 —1.0 —4.1 —3.4 —3.5 —1.5 —0.9 —1.4 —0.7 —0.3 —3.1 —2.7 + 1.0 + 1.4 +3.6 +3.2 +3.4 +0.4 —2.4 —0.3 —2.3 +1.9 —1.6 —2.3 +0.9 +0.2 —2.3 +0.5 —1.3 +2.2 —1.1 —2.6 +0.9 +3.1 —3.9 —1.4 —3.1 777777. —51.6 —50.2 —18.4 —45.7 —44.3 —44.9 —45.2 —42.5 —46.0 —48.8 ^(5.7 —47.3 ^18.0 —18.2 —49.2 —53.3 —56.7 —60.2 —61.7 —62.6 —64.0 —64.7 —65.0 —68.1 —70.8 -69.8 —68.4 —64.8 —61.6 —58.2 —57.8 -60.2 —60.5 —62.8 —60.9 —62.5 —64.8 —63.9 —63.7 —66.0 —65.5 —66.8 —64.6 —65.7 —68.3 —67.4 —64.3 —68.2 —69.6 —72.7 Ill 112 113 Q e Re s 8 114 115 116 T, U, 117 118 119 120 V, 121 122 123 124 w, X, 125 126 127 Y„ z 8 128 129 A, B, 5 130 131 132 133 D, E, 134 135 F, O, 136 137 138 H, I, 139 140 141 km. 166.130 167. 153 168.245 169. 192 169. 418 169. 948 171.009 172. 147 173.519 174.595 176. 250 177. 522 177. 975 179.112 180.188 181. 278 182. 195 183.281 184.446 185.465 186.626 186.683 187. 107 188.227 189.473 190. 679 191. 475 192.680 194. 177 195. 175 195. 577 196. 717 197. 437 198. 619 199.827 200.588 201.798 201.896 202.920 204.064 205.421 20& 357 207.560 208.759 209.875 210.200 211. 526 212. 771 213. 980 215. 107 771. 21.2690 Do 20.5079 Do 20.7267 Do 18.0309 Apr. 22-22 Do 18. 3452 Apr.23-23 16.5083 Apr. 22-23 14. 7775 Do 13. 2891 Apr.23-23 11.1119 Do Do 6.8540 Do 0.2490 Apr.23-24 6.6076 Apr.24-24 6.6306 Do 6.6455 Do 6.8521 Do 8.2985 Do 7.3605 Do 6.s)547 Apr.24-25 7.2763 Apr. 25-25 7.0419 Do 6. 1975 Do 6.8729 Do 6.0621 Do 6.1165 Do 6.5083 Do 5.9039 Do 6.9552 Apr. 26-26 Apr. 25-26 6.3319 Apr. 26-26 5.9411 Apr.26-25 5. 4059 Apr. 26-26 4.2818 Do 5. 3155 Do 5. 4767 Do 6.8357 Apr.26-27 6.4881 Apr. 27-27 6.7254 Do 5.9974 Do 7.0848 Do 6.4407 Apr.27-29 6.4227 Apr. 29-29 6.2723 Do 8.5611 Do 8.0410 Do 8.8012 Do 9.5169 Do 8. 7417 Apr. 30-29 10. 1879 Apr. 30-30 Apr.29-29 10.9427 Apr. 29-30 11.3515 Apr.30-30 11.9741 Do ( 111 I — OoT -B.SBB i. ;.■•. - n.:«x3 -fU -». i J9 21.5. 175 11.54.581 Do 141-149 142-143 143-144 144-145 145- Kj Ki-146 146- La Lt-147 147-148 147-148 147-148 148-M» M,-149 149-150 149-150 150-151 151-Nj Nn-Oj Oj-152 152-153 153-154 154-155 155-Pj Pt-156 156-157 157-158 158-159 159-Q» Qs-160 160-161 160-161 161-162 162-163 163-164 164-165 165-R, 1 165-R, 1. 12:. 1.105 1.106 1.024 0.405 1.189 1.055 1.181 1.167 1.167 1. 107 0.365 1.122 1.072 1.072 1.127 0.644 0.804 1.124 1.253 1.167 1.165 1.116 1.041 1.124 1.134 1.123 0.972 1.161 1.105 1.105 1.145 1.098 1.124 1.143 0.372 0.372 + 0.3.W + 0.8472 + 0.4596 + 0.4184 — 0.0825 + 1.7290 + 0. 1364 + 4.1447 — 2. 7217 — 2. 7256 — 2.7266 — 1.0375 + 0.4800 — 0. 6293 — 0.6327 — 0. 5167 — 0.0836 — 0. 5800 — 0. 2770 + 0.3961 — 3.2235 + 2.5043 — 0.2230 + 1.1967 — 1.4195 — 0.9970 + 1.0675 — 0.6024 — 2.1576 + 0.3417 + 0.3461 + 0. 1271 + 0.5866 + 1.1539 + 1.8150 — 0.8676 — 0.8649 ■ -0.3579 — 0.8463 — 0. 4595 — 0.42O4 + 0.0826 — 1. 7295 — 0. 1367 — 4.1458 + 2.7282 + 2.7312 + ITBBJ + 0.8468 + 0.4596 + 0.4194 - 0. 0826 + 1.7295 + 0. 1366 + 4.1452 I — 2.7272 - 1.0367 + 0.4819 | — 0.6323 - 0. 5182 - 0.0822 - 0.5803 - 0. 2784 + 0.3950 - 3.2249 + 2.5036 - 0.2233 + 1.1972 - 1.4206 - 0.9959 + 1.0682 - 0.6024 - 2.1580 | + 0.3448 + 0.1272 + 0.5872 + 1.1556 - 1.8144 } - 0.8553 -0.9 —0.9 —0.1 +2.0 —0.1 —0.1 +0.3 +1.1 —5.1 +1.6 +2.6 —2.6 —2.9 +2.9 —0.6 —2.7 —0.9 -2.8 -1.4 -0.6 + 1.1 -2.2 +2.2 + 1 4 -0.1 -0.7 + 1.7 +0.2 + 1.2 +3.3 -1.2 + 1.8 —73. (i —74.5 —74.6 —72.6 —72.7 —72.8 —72.5 —71.4 —76.5 —74.9 —72.3 —74.9 —77.8 —74.9 —75.5 —78.2 —79.1 -81.9 -83.3 -83.9 -82.8 -85.0 -82.8 -81 4 -81.5 -82.2 -80.5 -80.3 -79.1 -75.8 -77.0 -75.2 112 143 144 145 K, 146 L. 147 148 Mg 149 150 151 N, O, 152 153 154 155 P. 156 157 158 159 Q» 150 161 162 163 164 165 R, 210. 9S9 217. 337 2ia 443 219. 467 219. 872 221.081 222.116 223.297 224.464 224.829 225.951 227.023 228. 150 228.794 229.598 230. 722 231. 975 233. 142 234.307 235.423 236. 464 237. 588 238.722 239 845 240.817 241.978 243.083 244-228 245.326 246.450 247.593 247.965 12.3525 Do 13. 1793 Do 13. 6389 Do 14.0583 May 1-2 13.9757 Do 15.7053 May 1-1 15. 8419 Do 19.9871 Do May 2-2 17.2599 May 2 May 1-1 + 1.0359 - 0.4832 + 0.6347 + 0.6324 + 0.5196 + 0.0807 + 0.5806 + 0.2797 - 0. 3952 + 3.2263 - 2.6029 + 0.2236 - 1.1978 + 1.4217 + 0.9948 - 1.0689 + 0.6025 + 2.1583 - 0.3462 - 0.3450 - 0. 1273 - 0.5878 - 1.1572 - 1.8138 + 0.8648 + 0.8641 16.2232 Do 16. 7051 May 1-2 16.0728 May 3-3 May 2-2 15.5546 Do... 15. 4724 Do 14.8921 May 2-3 14.6137 May 3-3 15.0093 Do 11.7844 Do 14.2880 Do.... 14.0647 May 6-6 15.2619 Do 13.8413 Do 12.8454 Do 13 9136 May 6-7 13.3112 May 7-7 11.1532 Do . 11.4980 May 9-9 . May 7-7 11.6252 Do 12.2124 Do 13.3680 May 7-10 15.1824 14.3171 PKECISE LEVELING, BRIGHAM TO SAN FBANCISCO. Results of leveling, San Francisco, Cal., to Marmol, Nev. — Continued. 23 Date. From B. M. to B. M. 1912. May 10-10. Do Do.... Do. ... May 11-11.. May 10-11.. Do.... May 11-11. . Do Do.... Do.... May 13-11. . May 13 May 13-13. . Do Do.... Do.... Do.... Do.... May 14-13. . May 14-14. . May 15-14. . Do Do.... May 15-15. . Do Do.... Do.... Do.... Do.... May 16-16. . Do.... Do.... Do.... Do.... Do.... Do.... Do.... May 16-17. . May 17-17.. Do.... Do.... Do.... Do.... Do.... May 17-18. . May 18-18. . Do Do Do May 21-21.. May 18-21. . May 21-21. . Do.... Do May 22-22. . May 21-21.. May 22-22. . May 21-21. . May 23-23. . Do Mav 25-23. . May 23-24. . Do Do Do Do May 24-24. . Do Do Do May 24-27. . May 27-27. . Do Do Do Do May 28-28. . Do Do Do Do Do May 28-29. . Do Do Do May 29-29. . Do May 30-30. . May 29-29. . Do R»-166 166-167 167-168 168-169 168-169 169-S, 8,-170 170-171 170-171 171-172 172-173 173-T, 173-T, T,-174 174-175 174-175 175-176 176-177 177-178 178-U, Uj-179 179-180 180-181 181-V, V.-182 182-183 183-184 184-185 185-186 186-W, W»-187 187-188 188-189 189-190 190-191 191-Xb Xo-192 192-193 193-194 194-195 195-196 196-197 197-198 198-199 199-200 20D-Y. Y.-201 201-202 202-Z, Z„-203 Zj-203 203-204 204-Aio Aio-205 205-Bio 205-Bio Bio-206 B io-206 206-207 207-208 208-209 209-210 210-Cio Cm-211 211-212 212-213 213-214 214-215 215-216 216-217 217-218 218-219 219-220 220-221 221-Dio D,o-222 222-223 223-224 224-225 225-226 226-227 227-228 227-228 228-E, E io-229 229-230 230-231 231-232 232-233 232-233 233-234 234-235 Distance in kilo- meters. 0.797 1.153 1.124 1.204 1.204 1.276 1.118 0.536 0.536 1.124 1.164 1.097 1.097 0.419 1.152 1.152 1.430 0.925 1.236 1.281 0.755 1.146 1.674 1.414 1.281 1.239 1.150 0.670 0.568 0.431 0.879 1.063 1.126 1. 165 1.123 0.516 1.209 1.117 0.864 1.206 1.242 1.116 1.123 1.204 1.196 0.836 1.151 1.083 0.855 1.179 1.179 1.370 0.686 1.115 0.708 0.708 1.139 1.139 1.165 0.381 1.064 1.012 0.806 1.093 1.042 1.118 1.110 1.341 1.187 1.201 1.179 1.100 1.182 1.092 1.135 0.328 0.999 1.082 1.200 1.150 1.156 1.166 1.166 0.423 0.943 1.070 0.848 1.219 1.248 1.248 1.121 1.116 Difference of elevation. Forward line. m. - 0.3208 + 0.7143 + 0.7090 - 0.6267 - 0.6280 + 0.4048 - 1.5941 - 0. 1397 - 0. 1408 - 0.7087 - 0.5540 - 0.8306 + 0.9336 + 0.5358 + 0.5322 - 0.4521 - 0.0137 - 0.0328 - 1.2735 + 1.3613 - 0.0301 + 0.5849 + 2.2413 - 0.2640 - 0. 1783 - 1.0837 - 0.4063 + 0.3017 - 1.4147 + 1.2158 - 1.8684 + 2.6630 + 0.6263 - 0.3541 + 1.4658 4- 2.1297 + 3.4555 + 1.3824 + 3.9729 + 4.8325 + 4.4840 + 4.2233 + 4.7555 + 4.0077 - 1.4141 - 1.4445 - 1.3679 - 0.3080 - 2.7074 - 2.7104 + 4.9220 + 1.9622 + 3.7930 + 0.0432 + 0.0432 + 6.5651 + 6.5697 + 5.4990 + 0.2591 + 5.1238 + 5.5770 + 1.0782 + 16.7259 + 1.4817 + 12.6253 + 14.3317 +13.8172 +20.0855 +24.4965 +23.7184 +21.8112 +23.9550 +25.9405 +21.6887 + 4.5922 +25.0851 +23.7269 +24.0176 + 16.5361 + 6.9047 + 12.3755 + 12.3773 + 3.5623 + 9.9482 + 12.4583 + 17.5067 +21.7155 + 17.8177 + 17.8193 + 1.6038 + 17.3709 Backward line. m. + 0.3185 - 0.7149 - 0.7052 + 0.6221 + 0.6250 - 0.4047 + 1.5917 + 0. 1434 + 0.1433 + 0.7112 + 0.5538 + 0.8305 + 0.8288 - 0.9347 - 0.5309 - 0.5323 + 0.4519 + 0.0100 + 0.0317 + 1.2717 - 1.3626 + 0.0293 - 0.5867 - 2.2408 + 0.2596 + 0.1780 + 1.0851 + 0.4060 - 0.3021 + 1.4151 - 1.2173 + 1.8689 - 2.6661 - 0.6234 + 0.3533 - 1.4657 - 2.1284 - 3.4557 - 1.3833 - 3.9760 - 4.8353 - 4.4826 - 4.2209 - 4.7582 - 4.0105 + 1.4173 + 1.4463 + 1.3692 + 0.3068 + 2.7029 + 2.7087 - 4.9215 - 1.9617 - 3.7961 - 0.0478 - 0.0416 - 6.5696 - 6.5684 - 5.4973 - 0.2594 - 5.1204 - 5.5800 - 1.0778 -16.7270 - 1.4820 -12.6273 -14.3304 -13.8179 -20.0885 -24.4963 -23.7194 -21.8115 -23.9530 -25.9374 -21.6871 - 4.5919 -25.0853 -23.7248 -24.0183 -16.5372 - 6.9039 -12.3798 -12.3777 - 3.5609 - 9.9498 -12.4610 -17.5073 -21.7159 -17.8129 -17.8162 - 1.6041 -17.3679 Mean. - 0.3196 + 0.7146 + 0.7071 }• - 0.6255 + 0.4048 - 1.5929 \ - 0.1418 - 0.7100 - 0.5539 \ - 0.8301 + 0.9342 \ + 0.5328 - 0.4520 - 0.0118 - 0.0322 - 1.2726 + 1.3620 - 0.0297 + 0.5858 + 2.2410 - 0.2618 - 0. 1782 - 1.0844 - 0.4062 + 0.3019 - 1.4149 + 1.2166 - 1.8686 + 2.6646 + 0.6248 - 0.3537 + 1.4658 + 2.1290 + 3.4556 + 1.3828 + 3.9744 + 4.8339 + 4.4833 + 4.2221 + 4.7568 + 4.0091 - 1.4157 - 1.4454 - 1.3686 - 0.3074 • - 2.7074 + 4.9218 + 1.9620 + 3.7946 ■ + 0.0440 • + 6.5682 + 5.4982 + 0.2592 + 5.1221 + 5.5785 + 1.0780 + 16.7264 + 1.4818 + 12.6263 + 14.3310 + 13.8176 +20.0870 +24.4964 +23.7189 + 21.8114 +23.9540 +25.9390 +21.6879 + 4.5920 +25.0852 +23.7258 +24.0180 +16.5366 + 6.9043 + 12.3776 + 3.5616 + 9.9490 + 12.4596 + 17.5070 +21.7157 + 17.8166 + 1.6040 + 17.3694 Discrepancy. Par- tial. 771771. +2.3 +0.6 -3.8 +3.8 -0.1 +2.4 -3.2 -2.5 +0.2 + 1.0 + 1.1 -2.4 +0.2 +3.7 + 1.1 + 1.8 +1.3 +0.8 + 1.8 -0.5 +4.4 +0.3 -1.4 +0.3 +0.4 -0.4 + 1.5 -0.5 +3.1 -2.9 +0.8 -0.1 -1.3 +0.2 +0.9 +3.1 +2.8 -1.4 -2.4 +2.7 +2.8 -3.2 -1.8 -1.3 +1.2 +3.1 -0.5 -0.5 +3.1 + 1.5 + 1.6 -1.7 +0.3 -3.4 +3.0 -0.4 + 1.1 +0.3 +2.0 -1.3 +0.7 +3.0 -0.2 + 1.0 +0.3 -2.0 -3.1 -1.6 -0.3 +0.2 -2.1 +0.7 +1.1 -0.8 +2.4 -1.4 + 1.6 +2.7 +0.6 +0.4 -3.9 +0.3 -3.0 Total accu- mu- lated. mm. -72.9 -72.3 -76.1 -72.3 -72.4 -70.0 -73.2 -75.7 -75.5 -74.5 -73.4 -75.8 -75.6 -71.9 -70.8 -69.0 -67.7 -68.9 -65.1 -65.6 -61.2 -60.9 -62.3 -62.0 -61.6 -62.0 -60.5 -61.0 -57.9 -60.8 -60.0 -60.1 -61.4 -61.2 -60.3 -57.2 -54.4 -55.8 -58.2 -55.5 -52.7 -55.9 -57.7 -59.0 -57.8 -54.7 -55.2 -55.7 -52.6 Designa- tion of B. M. -51.1 -49.5 -51.2 -50.9 -54.3 -51.3 -51.7 -50.6 -50.3 -48.3 -49.6 -48.9 -45.9 -46.1 -45.1 -44.8 -46.8 -49.9 -51.5 -51.8 -51.6 -53.7 -53.0 -51.9 -52.7 -50.3 -51.7 -50.1 -47.4 -46.8 -46.4 -50.3 -50.0 -53.0 156 167 168 169 170 171 172 173 T, 176 177 178 U, 179 180 181 V, 182 183 184 185 186 W, 187 188 189 190 191 X. 192 193 194 195 196 197 198 199 200 Y„ 201 202 Z, 203 204 Aio 205 206 207 208 209 210 Cio 211 212 213 214 215 216 217 218 219 220 221 Dio 222 223 224 225 226 227 228 Ei, 229 230 231 232 233 234 235 Distance from B. M. City 635. km. 248. 762 249.925 251.049 252.253 253.529 254.647 255.183 256.307 257.471 258.568 258.987 260. 139 261.569 262.494 263. 730 265.011 265. 766 266.912 268.586 270.000 271. 281 272. 520 273.670 274.340 274.908 275.339 276.218 277. 281 278.407 279.572 280. 695 281.211 282.420 283.537 284.401 285.607 286.849 287.965 289.088 290.292 291.488 292.324 293.475 294.558 295.413 296.592 297.962 298.648 299.763 300.471 301.610 302.775 303.156 304.220 305. 232 306.038 307. 131 308. 173 309.291 310.401 311.742 312.929 314.130 315.309 316.409 317.591 318.683 319.818 320. 146 321.145 322. 227 323.427 324.577 325.733 326.899 327.322 328.265 329.335 330. 183 331.402 332.650 333.771 334.887 Observed elevation above mean sea level. m. 13.9975 14.7121 15.4192 14.7937 15.1985 13.6056 13.4538 12.7538 12.1999 11.3698 12.8368 12.3848 12.3730 12.3408 11.0682 12.4302 12.4005 12.9863 15.2273 14.9655 14.7873 13.7029 13.2967 13.5986 12. 1837 13.4003 11.5317 14.1953 14.8211 14.4674 15. 9332 18.0622 21.5178 22.9006 26.8750 31.7089 36. 1922 40.4143 45. 1711 49. 1802 47.7645 46.3191 44.9505 44.6431 41.9357 46.8575 48.8195 52.6141 59.2263 64.7245 64.9837 70. 1058 75.6843 76.7623 93.4887 94.9705 107.5968 121.9278 135.7454 155.8324 180.3288 204.0477 225.8591 249.8131 275.7521 297.4400 302.0320 327.1172 350.8430 374.8610 391.3976 398.3019 410.6795 414.2411 424. 1901 436.6497 454. 1567 475.8724 493.6890 495.2930 512.6624 24 U. S. COAST AND GEODETIC SURVEY SPECIAL PUBLICATION NO. 22. Results of leveling, San Francisco, Cal., to Marmol, Nev. — Continued. Date. From B. M. to B. M. Distance in kilo- meters. Difference of elevation. Forward line. Backward line. Mean. Discrepancy. Par- tial. Total accu- mu- lated. Designa- tion of B. M. Distance from B. M. City 635. Observed elevation above mean sea level. 1912. May 29-31 May 31-31 May 30-30 Do Do Do Do May 31-31 Do Do June 3-3 May 31-31 Do June 3-3 Do Do Do Do June 4-4 Do Do Do Do June 4-5 June 5-5 Do June 5-6 June 6-6 Do Do Do Do Do Do June 6-7 June7 June 8-8 June 7-7 June 8-8 June 7-7 Do June 8-8 June 7-8 June 8-8 Do Do June 8-10 June 10-10 Do Do Do Do June 13-14 June 10-14 June 14-14 June 13-14 Do June 14-14 June 13 June 15-15 June 13-14 Do Do June 15-15 Do June 17-17 June 15-15 Do June 17-17.... Do June 18-18 June 17-17 Do Do Do June 18-18 Do Do Do Do Do June 18-20 June 20-20 Do Do Do Do Do June 21-20 June 21-21 235-236 235-236 236-237 237-F,„ Fio-238 238-Gio Gio-239 239-240 240-241 241-242 241-242 242-243 243-244 243-244 244-245 245-246 246-247 247-H,o Hio-248 248-249 249-250 250-251 251-Iio Iio-252 252-253 253-Jio Jio-254 254-255 255-256 256-257 257-258 258-259 259-260 260-261 261-262 262-263 262-263 263-264 283-264 264-Kio Kio-265 Kin 265 265-266 266-267 267-268 268-269 269-270 270-271 271-272 271-272 272-Lio Lto-273 Lio-273 273-274 273-274 274-275 275-276 275-276 276-277 276-277 277-278 278-279 279-Mio Mio-280 280-281 281-282 282-283 283-Nio Nio-284 284-285 284-285 285-286 286-287 287-288 288-289 289-290 290-291 291-O 10 O io-292 292-293 293-294 294-295 295-296 296-297 297-298 298-299 299-300 300-301 301-302 302-303 1.171 1.171 1.116 0.688 1.120 1.071 1.154 1.134 1.024 1.099 1.099 1.180 1.119 1.119 1.195 1.003 0.976 0.386 1.128 1.118 1.102 1.098 0.761 1.076 1.139 1.005 0.885 1.154 1.183 1.079 1.190 1.152 1.179 0.886 0.965 1.159 1.159 1.097 1.097 0.884 1.078 1.078 0.914 1.101 1.092 1.088 0.497 1.093 1.092 1.092 0.944 1.038 1.038 0.837 0.837 1.289 1.295 1.295 1.299 1.299 1.291 1.295 1.437 0.986 0.944 0.260 1.002 0.681 1.006 0.997 0.997 0.999 0.998 0.987 0.996 1.000 0.993 0.300 1.013 1.079 1.000 0.225 0.220 1.141 1.183 1.144 1.054 1.182 1.073 1.089 + 13.5697 + 13.5735 + 7.4743 + 1.4563 +11.3428 +22. 7227 +19. 9707 +22.6956 +21.2278 +21.9504 +21.9523 +23.6097 +15.6731 +15.6773 - 0.7227 + 0.0813 + 1.3804 + 4.6663 - 4.3546 + 6.4256 + 16.4008 +11.4355 + 6.4652 - 2.1380 - 4.0866 + 2. 1232 + 17.5293 +22. 1958 +25.4462 +21.4982 +22.6055 + 14.0240 +22.6599 + 15.4772 +11.1318 (') +22.2132 +22. 9247 +22.9228 + 17.3219 +15.0453 +15.0498 + 4.4092 +22.0597 +22.3830 +23.0163 +10.3424 +24.1956 +24.4290 +24.4301 +22.1225 + 19.2222 + 19.2189 + 18.5748 +18.5746 +28. 1738 +28. 3798 +28.3803 +28.9543 +28.9555 +28.5796 +28.7109 +31. 1632 +21.4629 +20.9333 + 5.7555 +20.9079 + 14.1001 +18.9429 +20.3287 +20.3284 +20.8690 +20.8402 +21.2308 + 18.2097 + 16.9239 + 16.2778 + 5.0827 + 14.9183 + 19.6415 +17.9413 + 3.8387 + 4.1097 +20.5586 +21. 1530 +20.9799 + 8.8671 +15.6842 +17.0593 +15.5451 m. -13.5748 -13.5730 - 7.4757 - 1.4561 -11.3450 -22.7222 -19.9680 -22.6968 -21.2266 -21.9545 -21.9542 -23.6128 -15.6788 -15.6761 + 0.7229 - 0.0802 - 1.3791 - 4.6672 + 4.3563 - 6.4228 -16.4031 -11.4378 - 6.4652 + 2.1353 + 4.0875 - 2.1237 -17.5279 -22. 1943 -25.4439 -21.4977 -22.6054 -14.0218 -22.6609 -15.4789 -11.1309 -22.2113 -22.2103 -22.9180 -22.9209 -17.3204 -15.0510 -15.0496 - 4.4114 -22.0596 -22.3805 -23.0179 -10.3426 -24. 1932 -24.4237 -24.4295 -22.1230 -19.2178 -19.2224 -18.5706 -18.5742 -28. 1714 -28.3749 -28.3786 (') -28.9548 -28. 5774 -28. 7124 -31. 1613 -21.4656 -20.9350 - 5.7564 -20.9059 -14.0992 -18.9410 -20.3245 -20.3278 -20.8709 -20.8397 -21.2328 -18.2075 -16.9264 -16.2781 - 5.0816 -14.9223 -19.6422 -17.9428 - 3.8395 - 4.1094 -20.5625 -21.1519 -20.9779 - 8.8677 -15.6835 -17.0577 -15.5458 m. + 13.5728 + 7.4750 + 1.4562 +11.3439 +22.7224 +19.9694 +22.6962 +21.2272 +21.9529 +23.6112 +15.6763 - 0.7228 + 0.0808 + 1.3798 + 4.6668 - 4.3554 + 6.4242 + 16.4020 +11.4366 + 6.4652 - 2.1366 - 4.0870 + 2.1234 +17.5286 +22.1950 +25.4450 +21.4980 +22.6054 + 14.0229 + 22.6604 +15.4780 +11.1314 +22.2120 +22.9216 +17.3212 +15.0490 + 4.4103 +22.0596 +22.3818 +23.0171 + 10.3425 +24.1944 +24.4281 +22.1228 + 19.2204 + 18.5736 +28. 1726 +28.3784 +28. 9548 +28. 5785 +28. 7116 +31.1622 +21. 4642 +20.9342 + 5.7560 +20.9069 + 14.0996 +18.9420 +20.3274 +20. 8700 +20.8400 +21.2318 + 18.2086 + 16.9252 + 16.2780 + 5.0822 + 14.9203 + 19.6413 +17.9420 + 3.8391 + 4.1096 +20.5606 +21. 1524 +20.9789 + 8.8674 + 15.6838 + 17.0585 +15.5454 +2.3 + 1.4 -0.2 +2.2 -0.5 -2.7 +1.2 -1.2 +3.0 +3.1 +2.2 -0.2 -1.1 -1.3 +0.9 -1.7 -2.8 +2.3 +2.3 0.0 +2.7 -0.9 +0.5 -1.4 -1.5 -2.3 -0.5 -0.1 -2.2 +1.0 +1.7 -0.9 -2.4 -4.4 -1.5 +2.7 +2.2 -0.1 -2.5 +1.6 +0.2 -2.4 -3.0 +0.5 -0.5 -2.3 -2.4 -3.2 -0.1 -2.2 +1.5 -1.9 +2.7 + 1.7 +0.9 -2.0 -0.9 -1.9 -2.4 +1.9 -0.5 +2.0 -2.2 +2.5 +0.3 -1.1 +4.0 +0.7 +1.5 +0.8 -0.3 +3.9 -1.1 -2.0 +0.6 -0.7 -1.6 +0.7 -50.7 -49.3 -49.5 -47.3 -47.8 -50.5 -49.3 -50.5 -47.5 -42.2 -42.4 -43.5 -44.8 -43.9 -45.6 -48.4 -46.1 -43.8 -43.8 -41.1 -42.0 -41.5 -42.9 -44.4 -46.7 -47.2 -47.3 -49.5 -48.5 -46.8 -47.7 -54.5 -56.0 -53.3 -51.1 -51.2 -53.7 -52.1 -51.9 -54.3 -57.3 -56.8 -57.3 -59.6 -62.0 -65.2 -65.3 -67.5 -66.0 -67.9 -65.2 -63.5 -62.6 -64.6 -65.5 -67.4 -67.9 -68.4 -66.4 -68.6 -66.1 -65.8 -66.9 -62.9 -62.2 -60.7 -59.9 -60.2 -56.3 -57.4 -59.4 -58.8 -59.5 -61.1 -60.4 236 237 Fio 238 Gio 239 240 241 242 243 244 245 246 247 Hio 248 249 250 251 Ilo 252 253 Jio 254 255 256 257 258 259 260 261 262 263 264 K,o 265 266 267 268 269 270 271 272 Lio 273 274 275 276 277 278 279 M,o 280 281 282 283 N,o 284 285 286 287 288 289 290 291 O,o 292 293 294 295 296 297 298 299 300 301 302 303 km. 336.058 337.174 337.862 338.982 340. 053 341.207 342.341 343.365 344.464 345.644 346.753 347.958 348.961 349.937 350.323 351.451 352. 569 353.671 354.769 355.530 356.606 357.745 358.750 359. 635 360. 789 361.972 363. 051 364.241 365.393 366. 572 367.458 368.423 369.582 370.679 371.563 372. 641 373.555 374.656 375. 748 :!7<;. 836 377.333 378.426 379.518 380.462 381.500 382.337 383.626 384.921 386. 220 387. 511 388.806 390. 243 391.229 392. 173 392. 433 393. 435 394. 116 395. 122 396.119 397.118 398. 116 399. 103 400.099 401.099 402.092 402. 392 403. 405 404. 484 405.484 405. 709 405. 929 407. 070 408. 253 409. 397 410.451 411.633 412.706 413.795 m. 526.2352 533. 7102 535.1664 546. 5103 569.2327 589.2021 611.8983 633.1255 655.0784 678.6896 694.3659 693.6431 693.7239 695. 1037 699.7705 695.4151 701.8393 718.2413 729. 6779 736. 1431 734.0065 729.9195 732. 0429 749. 5715 771.7665 797.2115 818. 7095 841.3149 855. 3378 877.9982 893.4762 904.6076 926.8196 949.7412 967.0624 982. 1114 986. 5217 1008. 5813 1030. 9631 1053. 9802 1064.3227 1088.5171 1112.9452 1135.0680 1154.2884 1172.8620 1201.0346 1229. 4130 1258.3678 1286. 9463 1315.6579 1346. sroi 1368. 2843 1389. 2185 1394. 9745 1415. 8814 1429.9810 1448. 9230 1409.2504 1490. 1204 1510.9604 1532. 1922 1550.4008 1567. 3260 1583.6040 1588.6862 1003. 6065 1623.2483 1641. 1903 1645. 0294 1649. 1390 1669. 6996 1690. 8520 1711.8309 1720.6983 1736.3821 1753.4406 1768.9860 I Rejected in field. PRECISE LEVELING, BRIGHAM TO SAN FEANCISCO. Results of leveling, San Francisco, Cat, to Marmol, Nev. — Continued. 25 Date. From B. M. to B. M. Jane 21-21. Do.... Do.... June 22-22. Do.... Do.... Do.... Do.... June 24-24. Do.... Do.... Do.... June 26-26. Do.... Do.... Do.... Do.... Do June 27-27. Do Do Do Do June 27-29. June 28 June 29-29. June 28-28. Do Do Do July 1-1.... Do Do Do Do July 6-6.... Do Do July 2-2.... Do Do July3 July3-3.... Do July 3-2.... Do Do Do Do Do July 5-5.... July 6-6.... July 5-5.... Do Do Do Do Do Do July 8-8.... Do Do Do Do Do Do Do July9-fl.... Do Do Do Do July 9 July 10-10.. July 9-9.... July 10-10.. July 11-11 . . July 10-10.. Do July 10-11.. July 11-11.. Do Do Do Do July 12-12.. Do Do Do 303-304 304-Pio P,o-305 305-306 306-307 307-308 308-309 309-310 310-311 311-312 312-313 313-314 314-Qio Qio-315 315-316 316-317 317-318 318-319 319-320 320-321 321-Rm Rltr322 322-323 323-324 324-325 324-325 325-326 325-326 326-327 327-328 328-329 329-Sio Sio-330 330-331 331-332 332-333 333-334 334-Tio TV335 335-336 336-337 336-337 337-338 338-339 339-340 340-341 341-342 342-343 343-344 344-Uio Unr345 Uio-345 345-346 346-347 347-348 348-349 349-350 350-351 351-352 352-V 10 V„,-353 353-354 354-355 355-356 356-357 357-358 358-359 359-360 360-361 361-W,o W I0 -362 863-863 363-364 363-364 364-365 365-366 885-868 366-367 367-368 368-X,o Xio-369 369-370 370-371 371-372 372-Y,o Yio-373 373-D, D.-E, Er-F, Distance in kilo- meters. 1.183 1.100 1.097 1.060 1.099 1.221 1.228 1.158 1.124 1.216 1.117 1.081 0.289 0.862 1.106 1.143 1.083 1.038 1.330 1.083 1.149 0.779 0.996 0.932 1.091 1.091 1.219 1.219 1.123 0.662 1.041 0.969 0.648 0.842 1.040 0.523 0.821 0.679 0.505 0.989 0.958 0.958 1.027 0.900 1.066 1.060 0.963 1.061 0.981 1.123 1.178 1.178 1.071 1.106 1.144 1.178 1.079 1.080 1.080 0.756 1.090 1.083 1.080 1.032 1.080 1.080 1.076 1.141 1.080 1.019 1.094 1.061 1.009 1.009 1.088 1.080 1.080 0.964 1.038 0.602 1.079 1.224 0.818 0.714 0.894 1.128 0.828 0.921 0.103 Diflerence ot elevation. Discrepancy. Forward line. m. +20. 1214 +16.1330 + 16.0222 + 14.8408 + 16.7968 +18.9571 +17. 1302 +18.8207 +18.3130 +19.2307 +18. 2481 +17.3217 + 3.8663 +12.3081 +14. 1021 +16.2331 + 16.3500 +15. 1519 +22. 7926 +19. 1857 +21.9775 +11.3078 - 9.7794 -15. 7318 -19.3325 -19.3304 -20. 2618 -20. 2667 -18.6381 -11.2852 -18.4714 -15.1132 -11.8867 -14.4711 -17.8235 - 7.4008 -14.4426 -11.4040 - 8.3629 -16.9016 -10.6400 Backward line. - 7.9882 - 8.0324 -14.8053 -16.9283 -18.2706 -18.0310 -17.4063 -16.8868 -12. 4227 -12.4267 -10.0166 - 3.5131 - 5.4759 - 9. 8161 - 6.1066 - 9.2335 - 5. 1659 - 2. 1912 - 8.9198 - 8.7450 - 5.9497 - 6.1358 - 4.0053 - 4.0098 - 3.2569 - 8.8346 - 8.3375 - 2.8024 -14.9729 - 5.5120 (') -13.3414 -13.0748 - 7.9983 - 7.9984 - 9.4670 - 7.5637 - 3.9117 - 6.8315 -10.5289 - 5. 1045 - 5.7014 -11.0127 - 9. 1245 -10.0122 - 2.3403 - 0.4395 771. -20.1206 -16.1363 -16.0258 -14.8434 -16. 7967 -18.9571 -17.1325 -18.8250 -18.3123 -19.2303 -18.2483 -17.3199 - 3.8670 -12.3063 -14.1038 -16.2352 -16.3478 -15.1536 -22. 7964 -19. 1846 -21.9771 -11.3077 + 9.7794 + 15.7284 0) +19.3272 +20.2679 +20.2706 +18.6388 +11.2819 +18.4737 + 15.1162 +11.8874 + 14.4709 + 17.8225 + 7.4004 + 14.4431 + 11.4052 + 8.3632 +16.9004 + 10.6404 +10.6413 + 7.9877 + 8.0325 +14.8087 + 16.9304 +18.2699 +18.0318 + 17.4053 +16.8883 +12.4284 +12.4255 +10.0172 + 3.5142 + 5.4744 + 9.8139 + 6.1060 + 9.2333 + 5.1647 + 2. 1929 + 8. 9200 + 8.7467 + 5.9522 + 6.1386 + 4.0013 + 4.0113 + 3.2599 + 8.8326 + 8.3369 + 2.8023 +14.9727 + 5.5131 +13.3447 +13.3414 +13.0783 + 8.0026 + 7.9995 + 9.4675 + 7.5627 + 3.9136 + 6.8310 + 10.5302 + 5. 1039 + 5.70OO +11.0118 + 9. 1264 +10.0141 + 2.3422 + 0.4398 Mean. m. +20. 1210 + 16.1346 + 16.0240 + 14.8421 +16.7968 + 18.9571 +17. 1314 +18.8228 +18.3126 + 19.2305 +18.2482 +17.3208 + 3.8666 +12.3062 +14. 1030 + 16.2342 +16.3489 +15.1528 +22. 7945 + 19.1852 +21.9773 +11.3078 - 9.7794 -15.7301 -19.3293 " }- }" 20.2667 -18.6384 -11.2836 -18.4726 -15.1147 -11.8870 -14. 4710 -17.8230 - 7.4006 -14.4428 -11.4046 - 8.3630 -16.9010 10.6404 7.9880 8.0324 -14.8070 -16.9294 -18.2702 -IS. 0314 -17.4058 -16.8876 12.4258 -10.0169 - 3.5136 - 5.4752 - 9.8150 -6. 1083 - 9.2334 - 5.1653 - 2.1920 - 8.9199 - 8.7458 - 5.9510 - 6. 1372 - 4.0033 - 4.0106 - 3.2584 - 8.8336 - 8.3372 - 2.8024 -14.9728 - 5.5126 13.3422 -13.0766 - 7.9997 - 9.4672 - 7.5632 - 3.9126 - 6.8312 -10.5296 - 5. 1042 - 5.7007 -11.0122 - 9. 1254 -10.0132 - 2.3412 - 0.4396 Par- tial. }- mm. -0.8 +3.3 +3.6 +2.6 -0.1 0.0 +2.3 +4.3 -0.7 -0.4 +0.2 -1.8 +0.7 +0.2 + 1.7 +2.1 -2.2 + 1.7 +3.8 -1.1 -0.4 -0.1 0.0 +3.4 +4.2 -5.0 -0.7 +3.3 -2.3 -3.0 -0.7 +0.2 + 1.0 +0.4 -0.5 -1.2 -0.3 + 1.2 -0.8 +0.5 -0.1 -3.4 -2.1 +0.7 -0.8 + 1.0 -1.5 -2.3 Total accu- mu- lated. mm. -61.2 -57.9 -54.3 -51.7 -51.8 -51.8 -49.5 -45.2 -45.9 -46.3 -46.1 -47.9 -47.2 -47.0 -45.3 -43.2 -45.4 -43.7 -39.9 -41.0 -41.4 -41.5 -41.5 -38.1 -33.9 -38.9 -39.6 -36.3 -38.6 -41.6 -42.3 -42.1 -41.1 -40.7 -41.2 -42.4 -42.7 -41.5 -42.3 -41.8 -41.9 -45.3 -47.4 -46.7 -47.5 -46.5 -48.0 -50.3 Designa- tion ofB. M. -0.6 -50.9 -1.1 -52.0 + 1.5 -50.5 +2.2 -48.3 +0.6 -7.74 +0.2 -47.5 +1.2 -46.3 -1.7 -48.0 -0.2 -48.2 -1.7 -49.9 -2.5 -52.4 -2.8 -55.2 +4.0 -51.2 -1.5 -52.7 -3.0 -55.7 +2.0 -53.7 +0.6 -53.1 +0.1 -53.0 +0.2 -52.8 -1.1 -53.9 -1.6 -55.5 -3.5 -59.0 -2.6 -61.6 -0.5 -62.1 + 1.0 -61.1 -1.9 -63.0 +0.5 -62.5 -1.3 -63.8 +0.6 -63.2 + 1.4 -61.8 +0.9 -60.9 -1.9 -62.8 -1.9 -64.7 -1.9 -68.6 -0.3 -66.9 304 Pio 305 306 307 308 309 310 311 312 313 314 Qio 315 316 317 318 319 320 321 Rio 322 323 324 325 326 327 328 329 Sio 330 331 332 333 334 Tm 335 336 337 338 339 340 341 342 343 344 U l0 345 346 347 348 349 350 351 352 V,o 353 354 355 356 357 35S 359 360 361 W,o 362 363 364 365 367 368 Xio 369 370 371 372 Y,„ 373 D, E, F, Distance from B. M. City 635. km. 414. 978 416.078 417.175 418.235 419. 334 420.555 421.783 422.941 424.065 425.281 426.398 427.479 427.768 428.630 429.736 430. 879 431.962 433.000 434.330 435. 413 436. 562 437.341 438. 337 439. 269 440.360 441.579 442. 702 443.364 444. 405 445.374 446.022 446.864 447.904 448. 427 449.248 449.927 450.432 451.421 452.379 453.406 454.306 455. 372 456. 432 457.395 458.456 459. 437 460.560 461.738 462.809 463.915 465.059 466.237 467.316 468.396 469. 476 470. 232 471.322 472. 405 473. 485 474.517 475. 597 476. 677 477. 753 478. 894 479.974 480.993 482.087 483. 148 484. 157 485.245 486.325 487.289 488.327 488.929 490.008 491.2(2 492. 050 492. 764 493. 658 494.786 495. 614 496. 535 496. 688 Observed elevation above mean sea level. m. 1789. 1070 1805.2416. 1821.2656 1836. 1077 1852. 9045 1871. 8616 1888.9930 1907.8158 1926. 1284 1945.3589 1963. 6071 1980. 9279 1984. 7945 1997. 1007 2011.2037 2027. 4379 2043. 7868 2058. 9396 2081. 7341 2100. 9193 2122. 8966 2134. 2044 2124. 4250 2108.6949 2089.3656 2069.0989 2050.4605 2039. 1769 2020. 7043 2005.5896 1993. 7026 1979. 2316 1961.4088 1954.0080 1939. 5652 1928.1608 1919. 7976 1902.8966 1892.2562 1884. 2682 1876. 2358 1861.4288 1844. 4994 1826.2292 1808. 1978 1790. 7920 1773.9044 1761. 4786 1751. 4617 1747.9481 1742. 4729 1732. 6579 1726. 5516 1717. 3182 1712. 1529 1709.9609 1701.0410 1692. 2952 1686.3442 1680. 2070 1676. 2037 1672. 1931 1668. 9347 1660. 1011 1651. 7639 1648.9615 1633.9887 1628.4761 1615.1339 1602.0573 1594.0576 1584.5904 1577.0272 1573. 1146 1566. 2834 1555.7538 1550. 6496 1544.9489 1533.9367 1524.8113 1514.7981 1512. 4569 1512.0173 i Rejected in field. 26 U. S. COAST AND GEODETIC SURVEY SPECIAL PUBLICATION NO. 22. RATE OF PROGRESS. The average rates of progress for the two seasons were 73 miles per month in 1911 and 77.4 miles per month in 1912. The maximum progress in any one calendar month was 88 miles in 1911 and 87 miles in 1912. The average monthly progress for 28 seasons of precise leveling, as shown on page 30 of Special Publication No. 18, is 69.5 miles. The rates of progress for the two seasons leveling on the San Francisco-Brigham line are, respectively, 5 and 11 per cent greater than that average value. The maximum rates of progress attained in precise leveling by this survey in recent years are given on pages 14 and 15 of Precise Leveling in the United States, 1903-1907, and page 30 of Special Publication No. 18. COST OF LEVELING. The cost per mile of leveling during the season of 1911 was $14.09 ($8.75 per kilometer) while the cost of the leveling during the season of 1912 was $10.73 per mile ($6.67 per kilo- meter). The average cost per mile for the whole line was $11.90. This is in close agreement with the average cost for a number of seasons of leveling, which as stated on page 31 of Special Publication No. 18 is $11.10. The lower unit cost of the work in 1912 was due largely to the use of the motor velocipede car which made the rate of progress more rapid, to the longer season, and to the absence of heavy transportation charges on equipment at the beginning and end of the season. The places at which it was possible to get hotel accommodations for the party were closer together than in 1910. The increased experience of the observer, who was also the chief of party, was no doubt an additional factor. The above figures represent the actual cost of the leveling, including the establishment of the bench marks, with the exception of the cost of the instruments and stationery. It includes the transportation to and from the field paid by the Government and all wages and salaries, including those of the chief of party and recorder. The salary of the chief of party was charged to the leveling for the whole period during which he was engaged upon work incidental to the leveling, including the time spent in travel to and from the field, the time spent in preparing for the field, and in completing field reports, records, and computations at the end of the season. One-eleventh has been added to the salary actually paid the chief of party during the time he was connected with the leveling, to take account of the fact that the Government pays its permanent employees 12 months' salary for 11 months' work upon an average. In view of the unfavorable character of the country and the steep grades encountered, especially on the western end of the line, the cost of the work must be considered very satisfactory. ORGANIZATION OF PARTY. The party consisted of the chief, who made all of the observations, and 5 hands. One of these recorded the observations, 2 were rodmen, 1 held the sunshade, and 1 the wind shield. The equipment was practically the same as that used on previous lines. During the greater part of the season of 1911 two hand-driven velocipede cars were used to transport the party to and from the work and during the actual leveling. For several weeks at the end of the first season and during the entire season of 1912, one hand-driven velocipede car and one motor-driven velocipede car were used. During the first season the members of the party lived mostly in tents. At all except one of the headquarters they were able to obtain their meals at hotels, and thus they avoided the necessity of running their own mess. In 1912 it was possible to secure hotel accommoda- tions, both quarters and meals, throughout the season. For a detailed account of the usual organization and equipment and also the management of a precise leveling party, see pages 14 to 17 of Special Publication No. 18. PRECISE LEVELING, BRIGHAM TO SAN FRANCISCO. 27 CONNECTIONS WITH OTHER LEVELING. The western end of the leveling was started from four bench marks established by the engineering department of the city of San Francisco. The elevation of those marks had been determined by precise leveling from the tidal bench marks near the tidal station at the Presidio. At a number of places connections were made with bench marks of the United States Geological Survey. The bench marks of the Southern Pacific Railway were connected with the new leveling whenever practicable, and when of a substantial character were used instead of setting new permanent bench marks. Except in the case of the city bench marks in San Francisco all those of previous leveling with which connections were made, were given the United States Coast and Geodetic Survey designation letter followed by the initials of the organization which established the mark. AGREEMENT OF ELEVATIONS AT BRIGHAM, UTAH. The 1912 special adjustment of the level net, which is reported on in Special Publication No. 18, fixed the standard elevation of bench mark R at Brigham, Utah, as 1309.1505 meters, while the elevation of this mark, as given by the observed and unadjusted leveling from San Francisco, was 1309.1684 meters. The difference between the observed and standard elevations is only 0.0179 meter. The theoretically best value for bench mark R at Brigham, as determined by the 1912 adjustment, is 1309.1510 meters. This differs 0.0174 meter from the observed value. These agreements are so close that it is certain that the addition of this new line to the net in a new adjustment would change the elevations very little from those resulting from the 1912 special and general adjustments. CIRCUIT CLOSURES. The most severe test of the accuracy of the new line is the closing errors of the two circuits of which it forms a part. The unadjusted leveling in the loop Seattle-Brigham-San Francisco has a closing error of 0.2360 meter. The correction which would close this circuit of 2911 kilometers is 0.081 millimeter per kilometer. The closing error of the loop San Diego-Brigham-San Francisco, as given by the unadjusted levels, is 0.2612 meter. The correction which would close this circuit of 3027 kilometers is 0.086 millimeter per kilometer. These corrections . per kilometer are very small and compare most favorably with the smallest corrections per kilometer to close circuits, as shown on pages 72 and 73 of Special Publication No. 18. CORRECTION APPLIED. The line from San Francisco to Brigham was adjusted to the fixed elevations at those two places. The elevation at the former place was referred to mean sea level as zero and that at the latter was the standard elevation from the 1912 special adjustment. A correction of only 0.0125 millimeter per kilometer was necessary to make the lino fit the fixed elevations. PROBABLE AND SYSTEMATIC ERRORS. On page 88 of Special Publication No. 18 is given the resolution adopted by the Interna- tional Geodetic Association in 1912 in regard to leveling of high precision. The resoultion gives the following formulas with which to compute the accidental and systematic errors of leveling. For the probable accidental error, ij r , in the case of a set of lines, whether or not they form circuits, ,,.ip 2* y* 2 ~l Vr 91 IL (IL) 2 LJ 28 U. S. COAST AND GEODETIC SURVEY SPECIAL PUBLICATION NO. 22. For the probable systematic error, a r , in the case of a set of lines not forming a net, L denotes the length of an unconnected line, or the length of the side of a polygonal circuit in the case of a net; IL, the aggregate length of the set of lines, or of the net under consideration; A, the discrepancy between the results of the two runnings between consecutive bench marks; r, the distance between these two bench marks; s, the entire systematic discrepancy between the results of the two runnings, either for a whole line or for the side of a circuit. To obtain the s the process given by Lallemand in his "Nivellement de haute precision," page 713, was used. The accumulated discrepancy was plotted as ordinate against the dis- tance in kilometers from an initial bench mark as abscissa. The line connecting these points gave a somewhat irregular line which, nevertheless, showed, as a rule, a tendency to a fairly well-defined slope. A straight line was drawn by eye to represent as nearly as possible the tendency of the irregular line, and was tested to see whether the area between the irregular line and the straight line, lying above the latter, was equal to the area between the two lines and below the straight line. After a straight line was finally adopted the difference between the two ordinates corresponding to the two ends of the line of levels gave the value of s. The following table gives the values of the terms in the above formulas for each of the sections of the line from San Francisco to Brigham and also for the entire line. Section. Length of line L. System- atic dis- crepancy «. Number of sections JV. IJ' IT' »• L km. 486 4S1 497 mm. +73 —33 —26 435 434 483 1896 1584 1926 563 486 545 11.0 1.3 Total 1434 1352 5406 1594 ,'-V»|j .1434 ij r = ±0.646 14.7 '5406 1594 (1434) X 14. 7~] = l/9[3.770 - 0.01 1] = 0.418 r 9X1434 a r = ±0.034 =0.001139 The probable accidental error per kilometer for the whole line ij r = ±0.646 millimeter. The probable systematic error per kilometer for the whole line a r = ±0.034 millimeter. These errors indicate an accuracy much greater than that barely necessary for leveling of high precision which is given by the International Geodetic Association as a probable acci- dental error per kilometer of 1 millimeter and a probable systematic error per kilometer of ±0.2 millimeter. INSTRUMENTS USED. The leveUng instruments used were like the adopted model which is described in detail on pages 200 to 211 of Appendix 3 of the Report for 1903. A brief description of it, with two views, is given on page 7 of Special Publication No. 18. The regular type of self-reading rods was used. These are described on pages 415 and 416 of Appendix 8 of the Report for 1899. They are graduated to centimeters and on only one face. The rods were standardized in the United States Coast and Geodetic Survey office, both before and after each field season, and they were also measured by an especially designed tape PRECISE LEVELING, BEIGHAM TO SAN FRANCISCO. 29 at frequent intervals in the field. This tape and the way it is used are described on page 3 1 of this publication. The measurements in the field are sufficiently exact to indicate whether the rods maintain their lengths or actually change, and the amount of the change, if any. GENERAL INSTRUCTIONS FOR PRECISE LEVELING. The leveling was done in accordance with the following general instructions for precise leveling. These are also given on pages 8 to 12 of Special Publication No. 18, of the United States Coast and Geodetic Survey. 1. Except when specific instructions are given to proceed otherwise, all lines are to be leveled independently in both the forward and backward directions. 2. The distance between successive permanent bench marks shall nowhere exceed 15 kilometers. There shall be no portion of the line 100 kilometers long in which there are not at least 20 permanent bench marks. No perma- nent bench mark is to be counted in considering these limits unless it is adequately described, nor shall both of two bench marks be counted if they are placed bo near to one another and in such similar conditions of exposure as to be likely to be destroyed at the same time. The preceding statements refer to all permanent bench marks with which the leveling is directly connected, regardless of whether they are new bench marks or old ones established by other organi- zations. The above-stated limits are to be regarded as extreme lower limits. It is desired that the number of bench marks shall, in general, greatly exceed that just necessary to keep within the limits. A good example to emulate is a line run in New York State, in 1902, on which the average distance between bench marks was 2.5 kilometers. It is desired, also, that the bench marks in each general locality shall belong, in part, to each of several classes, such as bolts or other marks on buildings, squares cut or bolts or disks set in railroad masonry, such as bridge piers, water tanks, etc., stone posts, and iron-pipe bench marks. 3. The line of levels is to be broken by temporary bench marks into sections from 1 to 2 kilometers long, except where special conditions make shorter sections advisable. 4. Temporary bench marks should be established in places where they will be free from disturbance by the track hands working along the road or by materials unloaded from cars. This is especially important when the temporary bench mark is expected to hold the line for any considerable time. It is believed, however, that an undetected error caused by disturbance of the bench mark will be exceedingly rare, when two points, one set-up of the instrument apart, are used for holding the line. 5. At each city along the line, the leveling should be connected with at least two stable bench marks which are connected with the city datum. Connection should also be made with all stable bench marks of other organizations which may be found along the route. 6. In general, the top of rail of the railroad track should be used as the rod support. However, footpins should be carried along during the progress of the work, and they should be used whenever a train is known to be approaching or when there are special reasons for supposing the rail not to be in a sufficiently stable condition. 7. When elevations and descriptions of bench marks established by a railroad (over which a line is to be run) are furnished to this office with a request by the officials of the road to have the precise leveling done by this Survey con- nected with them, as many of the railroad bench marks will be incorporated in our line of levels as can be done without greatly delaying its progress. The railroad bench marks which are of a permanent nature are to be treated in the same manner as new permanent bench marks established by the precise leveling party. If the permanent bench marks of the railroad are chiefly of the same general type they must not be given full weight in deciding whether there are enough bench marks in any section of the line. (See paragraph 2.1 Bench marks of the railroad which are not of permanent character may be determined by extra foresights, as in the manner provided for determining the height of rail in front of a railroad station. (See paragraph 10.) It will not be necessary to connect the precise leveling with the railroad bench marks which are in places not easily accessible. It will not be necessary to connect with each railroad bench mark where they are less than 1 kilometer apart. The benefits derived from connecting a line of precise leveling with rail- road bench marks are: (a) That time is gained by having some permanent bench marks already established; (6) the elevations of the railroad bench marks resulting from the connection with precise leveling are of great value to the railroad concerned ; and, (c) as the work progresses, a check is obtained on gross mistakes which might escape notice, by comparing the elevations furnished by the railroad with those by the precise leveling party. 8. All old bench marks are to be called by their old names or numbers and are to be described fully by quoting the old description, if one is available, and by making additions or corrections to it. 9. All new bench marks are to be designated by capital letters with numerical subscripts after the alphabet has been exhausted in each State. 10. The elevation of the top of the railroad rail in front of each railroad station along the line of levels is to be determined with a check. This may be done by using the point on the rail as a rod support in either the regular forward or backward running of the line, or by taking an extra foresight to it on both the backward and forward run- nings, or by taking extra foresights to it from two instrument stations near it in one of the runnings of the line. 11. When it is desirable to get the elevations by means of which to compare the line of levels with the profile of the railroad, such elevations may be gotten by single readings on the rod held on top of the rail opposite water tanks and over bridges and culverts. Such structures are usually shown on the railroad profiles. 30 U. S. COAST AND GEODETIC SURVEY SPECIAL PUBLICATION NO. 22. 12. It is desirable that the backward measurement on each section should be made under different atmospheric conditions from those which occur on the forward measurement. It is especially desirable to make the backward measurement in the afternoon if the forward measurement was made in the forenoon, and vice versa. The observer is to secure as much difference of conditions between the forward and backward measurements as is possible without materially delaying the work for that purpose. 13. On all sections upon which the forward and backward measures differ in millimeters by more than 4.0VK (in which K is the distance in kilometers leveled between adjacent bench marks) both the forward and backward measures are to be repeated until the difference between two such measures falls within the limit. No one of the questioned measures is to be used with a new measure in order to get this agreement. 14. If any measure over a section gives a result differing by more than 6 millimeters from the mean of all the measures over that section, this measure shall be rejected. No rejection shall be made on account of a residual smaller than 6 millimeters unless there is some other good reason for suspecting an error in this particular measure, and in such cases the reason for rejection must be fully stated in the record. 15. Whenever a mistake, such as a misreading of 1 decimeter or 1 meter, or an interchange of sights (the back- sight being recorded as a foresight), is discovered in any measure after its completion and the necessary correction applied, such measure may be retained, provided there are at least two other measures over the same section which are not subject to any such uncertainty. Provided, further, that when it is found that the mistake was made on the last instrument station of the second running of a section and it is corrected on the same day and before beginning work on an adjacent section, such measure may be retained and no further measures of the section are to be required on account of the mistake. 16. The program of observation at each station is to be as follows: Set up and level the instrument. Read the three lines of the diaphragm as seen projected against the front (or rear) rod, each reading being taken to the nearest millimeter (estimated), and the bubble being held continuously in the middle of the tube (i. e., both ends reading the same). As soon as possible thereafter read the three lines of the diaphragm as seen projected against the rear (or front) rod, estimating to millimeters as before, and holding the bubble continuously in the middle of the tube. 17. At each rod station the thermometer in the rod is to be read to the nearest degree centigrade and the temperature recorded. 18. At stations of odd numbers the backsight is to be taken before the foresight, and at even stations the foresight is to be taken before the backsight. As the same rod is held on a rod station for both the fore and back sights, the effect of this is that the same rod is read first at each set-up, it being the rod used for the backsight at the first instru- ment station. 19. The difference in length between a foresight and the corresponding backsight must not exceed 10 meters. The difference is to be made as small on each pair of sights as is feasible by the use of good judgment without any expenditure of time for this particular purpose. 20. The recorder shall keep a record of the rod intervals subtended by the extreme lines of the diaphragm on each backsight, together with their continuous sum between each two contiguous bench marks (temporary or permanent). A similar record shall be kept for the foresights. The two continuous sums shall be kept as nearly equal as is feasible without the expenditure of extra time for that purpose, by setting the instrument beyond (or short of) the middle point between the back and front rods. The two continuous sums for a section shall not be allowed to differ by more than a quantity corresponding to a distance of 20 meters. 21. Once during each day of observation the error of the level should be determined in the regular course of the leveling and recorded in a separate opening of the record baok as follows: The ordinary observations at an instrument station being completed, transcribe the last foresight reading as part of the error determination, call up the back rod and have it placed about 10 meters back from the instrument, read the rod, move the instrument to a position about 10 meters behind the front rod, read the front rod and then the back rod. (The two instrument stations are between the two rod points.) The rod readings must be taken with the bubble in the middle of its tube. The required con- stant C to be determined, namely, the ratio of the required correction to any rod reading to the corresponding subtended interval, is p_ (sum of near rod readings) — (sum of distant rod readings) (sum of distant rod intervals)— (sum of near rod intervals)' The total correction for curvature and refraction must be applied to the Bum of the distant rod readings before using it in this formula. The level should not be adjusted if C is less than 0.005. If C is between 0.005 and 0.010 the observer is advised not to adjust the level, but if C exceeds 0.010 the adjustment must be made. If a new adjustment of the level is made, C should at once be redetermined. It is desirable to have the determination of level error made under the usual conditions as to length of sight, character of ground, elevation of line of sight above ground, etc. The adjustment of the instrument to reduce C must be made by inoving the level vial, not by moving the reticle. 22. Notes for future use in studying leveling errors shall be inserted in the record, indicating the time of beginning and ending the work of each section, the weather conditions, especially as to cloudiness and wind, and whether each section of the line is run toward or away from the sun. Such other notes should be made as promise to be of value in studying errors. 23. The instrument shall be shaded from the direct rays of the sun, both during the observations and when moving from station to station. PKECISE LEVELING, BKIGHAM TO SAN FRANCISCO. 31 24. The maximum length of sight shall he 150 meters, and the maximum is to he attained only under the most favorable conditions. 25. At the beginning and end of the season, and at least twice each month during the progress of the leveling, the 3-meter interval between metallic plugs on the face of each level rod shall be measured carefully with a steel tape, which shall be kept continuously with the party during the season for that purpose only. The temperatures shown by the thermometer inserted in the rod and by the thermometer attached to the tape at the time of each of these measures must be recorded. The purpose of these measures is to detect changes in the length of the rods and not to determine the absolute lengths. The absolute lengths are determined at the office between field seasons. 26. The tape furnished by the office for measurement of the rods is a piece of steel tape about 3.1 meters long, having near one end a fine line graduation and about 3 meters from it (at the other end of the tape) a series of fine millimeter graduations on a steel rule riveted to the tape. With this special form of tape the measurement of a rod should be made somewhat as follows: The rod should be supported at about the 0.85 meter and 2.45 meter points only (approximately quarter points) to get the least bending of the rod for any two-support system. In making the meas- urement the single line should be made to coincide with the fine line on the silver plug nearest the bottom of the rod and the reading should be made at the line on the silver plug at the top of the rod. It is possible to estimate the half tenths of millimeters on the rule which is attached to the tape. The tape should be placed on the face of the rod in such a way that the edge of the tape from which the steel rule does not project coincides with the edge of the face of the rod nearest the meter marks of the rod. Care must be taken that the two edges coincide closely in order that the tape may always assume exactly the same position. The end of the tape at the foot of the rod should be clamped firmly to the rod after the line on the tape and that on the plug have been made to coincide. The tape should then be smoothed down by the hand to make it lie perfectly flat on the face of the rod. With the hand lifted and, con- sequently, no tension on the tape, the reading should be made from the rule attached to the tape near the upper or top end of the rod. 27. The field computations and abstracts are to be kept up as the work progresses. As soon as each book of the original record is out of use it is to be sent to the office by registered mail. The corresponding abstracts must be retained until an acknowledgment of the receipt of the original record at the office has been received. 28. No duplicates of the original records are to be made except of the descriptions of bench marks, of which dupli- cates in the form of carbon copies are to be made. At least once during each month such carbon copies as have accu- mulated are to be sent to the inspector of geodetic work. 29. At least once each month, during the progress of the leveling, a test must be made of the adjustment of the rod levels, and a statement should be inserted in the record showing the manner in which the test was made, whether the error was found to be outside the limit stated below, and whether an adjustment was made. With the bubble of the level rod held at the center, the deviation from the vertical of the plane intersecting the center of the face of the rod throughout its length and normal to the face of the rod, must be determined. The deviation from the vertical of the plane coinciding with the face of the rod must also be determined. If the deviation from the vertical exceeds 10 millimeters on a 3-meter length of the rod, the rod level must be adjusted. 30. On the left-hand page of the record the number of each instrument station at which the instrument is not set up in the railroad track is to be included in parentheses. Similarly, on the right-hand page of the record the designat- ing letter for the foresight rod (V, W, etc.) shall be inclosed in parentheses, if said rod is not supported on the railroad rail. If the length of any portion of the level line run off the railroad is 25 meters or more greater than the railroad distance between the points of departure from and return to the railroad, then the distance along the track between these two points must be shown in the record. The purpose of these requirements is to furnish the office a means of detecting blunders in the leveling, by plotting the level line on the profile of the railroad. 31. When it is expected that the forward and backward runnings of the line are to be completed up to any one place, the elevation at that place should be held by two points, established at least one set-up of the instrument apart. When the leveling is continued from or to such a pair of points, the instrument should be set up between them and readings of the rod taken on each point. The same arrangement of points should be used at the completed end or ends of any detached portion of the line of levels. Either one of the two points may be used for carrying along the elevation, with the other used only as a check against mistakes in reading the rod, or a disturbance of one or both of them. The records should show clearly which one of the two points was used to carry the elevation, and it is believed that it is good policy to use the same point (backward or forward) in each case as far as may be practicable. It is believed that by employ- ing this method no mistake of a meter or a decimeter made in reading the rod, held on a bench mark, will escape detection. 32. As far as possible all the permanent bench marks should be in the main line of levels and not on spur or branch lines. One of the exceptions to this rule is where the line runs several miles off the railroad to the mark of a triangula- tion station. In such a case the spur, or branch line, is the more economical way of doing the work and will be satis- factory. Whenever a permanent bench mark is established by means of a spur, or branch line, which has only one set- up, the forward and backward lines of the spur or branch should be run at different times of a day or on different days, if practicable. If it should be necessary to have the two runnings made one immediately after the other, the height of the instrument should be materially changed to make the second measure. 33. Except in rare cases, the permanent bench marks should be established before or during the first running of the line. It is believed to be inadvisable to delay the tying in of the permanent bench marks until after the line has been run, even in only one direction. When it is impracticable to establish a permanent bench mark before or 32 U. S. COAST AND GEODETIC SUBVEY SPECIAL PUBLICATION NO. 22. during the first measurement of the line, an acceptable manner of tying in the permanent bench mark or including it in the main line of levels is to establish a temporary bench mark on both sides of the proposed location of the per- manent bench mark and to leave the distance between them unleveled until the permanent bench mark has been set. The arrangement of the temporary bench marks established for this purpose should be similar to that described in the latter part of paragraph 31 of these instructions. This would provide for two points, the difference in elevation between which are known, on each side of the permanent bench mark and the distance between the two pairs of points makes a section in the main line of levels. A diagram showing the arrangement of the stakes and the permanent bench mark is shown below: O X O X □ X O X O The positions of the instrument are shown by X , the positions of the temporary bench marks by O, and the position of the permanent bench mark by □■ 34. Chiefs of party should keep the length of sight great enough to make it necessary to do a moderate amount of rerunning. If an observer is extremely cautious and confines all his observations to sights sufficiently short to insure easy reading of the rod, it is possible to work month after month with almost no rerunning, but the progress will be slow. On the other hand, it is certain that an attempt to take sights of the limiting length, 150 meters, at all times would lead to a very large amount of rerunning and the progress would not be rapid. It is believed that the maximum speed consistent with the required degree of accuracy will be secured by continually keeping the length of sight such that the amount of rerunning will be from 5 to 15 per cent. An extremely small percentage of rerunning would indicate an excess of caution on the part of the observer. The occurrence of a moderate amount of rerunning is due largely to an attempt on the part of the observer to obtain the maximum progress consistent with the required degree of accuracy and not to inability to secure such observations that little or no rerunning would be necessary. Observers have found a convenient rule in fixing the length of sight to be to shorten the sights whenever the upper and lower thread intervals subtended on the rod are found to differ frequently by more than a selected limit. Each observer should fix the limit from his own experience by noting the relation between such a provisional limit and the amount of rerunning found to be necessary while using it. Such a rule is based upon the idea that the additional errors which are encountered when the length of sight is increased are, in the main, those due to the increasing acci- dental errors in reading the rods. 35. It is not thought advisable to state definitely in these instructions the allowable limit on the rate of divergence between the forward and backward lines, but this should be kept small. 36. The record and the preliminary or field computation of precise levels must conform to the examples given on pages 22 to 26 of Special Publication No. 18, except that in the computation shown on page 25 the five corrections for curvature and refraction, level, index, length of rod, and temperature are not to be applied in the field. 37. Should the experience of a chief of party indicate to him that a change or changes in these instructions would facilitate the work in the field, he is urged to communicate with this office regarding such changes. 38. When cases arise which are not provided for by these general instructions or by specific instructions, the chief of party will use his own judgment in the matter. Following the general instructions in Special Publication No. 18 there are given some ex- planations of them which, it is believed, need not be repeated here. STUDY OF ERRORS. 1 The errors in leveling are shown by the difference between the backward and forward runnings of the sections, the accumulated discrepancy of the line, and by the closing errors of the circuits. None of these, however, shows exactly what error may be present in any section of a hne. Constant errors due to erroneous values for the rod lengths and to undetected changes in rod lengths during the season are known to be small and may be considered negligible. The constant or systematic errors due to changes in the elevation of rod supports between the forward and backward readings are very small. The rod support is usually the top of the rail of the railroad, the exact place used for the rod point being marked with keel or some simi- lar substance. Wooden stakes are used as temporary bench marks. Wooden stakes or metal pins are used as the rod support for the short time when a train is known to be approaching or when the line is being run through a town or village. Metal plates are no longer used as rod supports. Country roads are used only on spur lines out to triangulation stations or to bench marks of other organizations which are not on railroads, with which it is desired to make connections. 1 The subject, errors In leveling, is discussed at length t>y Charles Lallemand in "Nivellement de Haute Precision" in the Encyclop&iie des Travaui Publics, Paris et Liege, 1912. PRECISE LEVELING, BBIGHAM TO SAN FRANCISCO. 33 It is possible to have appreciable errors due to the careless work of a rodman who might not place the rod in exactly the same position for the two sights, but it is believed that the effect of this would be largely accidental. It seems probable that unequal temperatures in different parts of the instrument can have only slight effect on the leveling. All parts of the instrument except the wooden tripod are shielded from the sun during the observations and while moving forward from one instrument station to another. The instrument is constructed of an alloy of nickel and iron which has a very low coefficient of expansion, only 0.000004 per degree Centigrade, and unequal heating of the different parts should have very little effect in distorting the instrument. Temperature effects are still further minimized by having the level vial set into the barrel of the telescope very close to the line of sight. The principal sources of accidental errors are believed to be: (a) Poor estimation of the millimeters in reading the rod; (6) reading the rod before the bubble has come to rest; (c) rapid changes in the vertical refraction. The principal sources of systematic error are probably: (a) Slow changes in the vertical refraction; (b) difference in the amount of the vertical refraction on the two sights on steep grades; (c) other atmospheric conditions which possibly depend upon the direction of the running, the time of day, whether the sky is clear or cloudy, and whether it is calm or windy. Some of the errors may be systematic in their effect on a single running of a line of levels, but the mean of two runnings over the same line under different conditions may minimize or entirely eliminate the effect. The effect of a gradual change in the vertical refraction is practically eliminated from even a single line by observing the back sight first at one station and the foresight first at the next station, and so on. It is impossible to eliminate the systematic errors of leveling from a single difference between two bench marks, but the method of procedure in the field is designed to make the effect of the systematic errors on any line or large section of it largely accidental. It is believed that the value of the accumulated difference between the forward and back- ward runnings does not give a definite value of the systematic error in a section of leveling. This will be discussed later. (See p. 42.) It is not easy to discover in the results of leveling the effect of any one condition or set of conditions when only two runnings of a line have been made. In order to do this with any degree of certainty, a line should be run many times, under many different conditions of weather, and with the sun at various azimuths. INVESTIGATION OF SYSTEMATIC ERRORS. A number of miles of leveling have been run in the United States over steep grades on which the errors of leveling seem to be greater, on an average, than those usually obtained when running over level ground. The observers of the United States Coast and Geodetic Survey, during a number of years past, have kept a record of the time of the mnnings of the different sections, with the weather conditions at the time the observations were made. Five lines of the leveling by this Survey have been selected for a study of the possible relations between the errors of leveling and the conditions of weather, the time of observations, and the grade. They are: No. Line. Distance. Direction of progress. Average length of section. San Francisco, Cal., to Marmol, Nev Beowawe to Marmol, Nev Brigham, Utah, to Beowawe, Nev.. . Butte to Devon, Mont Pocatello, Idaho, to Butte, Mont 53167°— 14 3 Kilometers. 497 451 486 461 415 Eastward . Westward. ...do Northward ...do Kilometers. 0.8 0.9 0.8 0.8 1.1 34 U. S. COAST AND GEODETIC SURVEY SPECIAL PUBLICATION NO. 22. The grades on some portions of these lines are as great as 2$ per cent, or a change in eleva- tion of 25 meters in 1 kilometer. The leveling over the above lines was, as usual, divided into sections which vary in length from something less than 1 kilometer to about 2 kilometers. Each section is run over twice, in opposite directions, and if the two differences in the elevations of the ends of a section do not agree in millimeters within the amount represented by 4.0 -y/K, where K is the length of the section in kilometers, one or more additional runnings are made. The data for the United States Coast and Geodetic Survey leveling do not give any clear idea as to the relation between the accidental errors and the conditions under which the work is done, for the observers are directed to make their lengths of sight at all times as long as possible, provided only that they shall never exceed 150 meters and that the difference in millimeters between the two runnings of a section shall not be greater than 4.0 ~JK. It seems reasonable to suppose that with the same length of sight on cloudy and on clear days, the accidental errors would be much smaller on the former, while under the actual condition of running when the cloudy-day sights are 150 meters and the clear-day sights only about half that length the acci- dental errors will be approximately the same. There remain the systematic errors which may be investigated. The subject of constant and systematic errors in precise leveling is an old one which has been discussed by many writers of different countries. Most of these errors are of such small amounts that it is difficult to separate them from the accidental errors. It is believed that the largest systematic errors are found in leveling over steep grades, and that the errors are functions of (1) the time of day, (2) the amount of sunshine, (3) the strength of wind, and (4) possibly the direction of the running, forward or backward, or toward or away from the sun. It being impracticable to investigate the relations between the size and sign of the discrep- ancy between the results of the two runnings of the sections and the many different grades, the leveling has been separated into only two classes : First, those sections with grades exceeding 10 meters/ and, second, the remainder of the sections. The following table gives the average grades for the lines of leveling under consideration: Mean grade per section. Lines. For sections with grades greater than 10 meters. For sections with grades less than 10 meters. For all sections. Meter: 17 15 14 18 19 16.6 Meter: 3 2 3 5 4 3.4 Meters. 8 2 S 9 Pocatello to Butte 1 6.4 RELATIONS BETWEEN THE DISCREPANCY AND THE TIMES OF RUNNING. The instructions issued to the observers direct that the two runnings of a section shall be made at different times of the day, if practicable. The following table gives the average discrep- ancies for the sections with the two runnings at the same time of the day and also for those which have one running in the morning and the other in the afternoon. In this discussion the direction of the line or sections is not considered. It is only the difference in the elevation of the ends of a section which is taken into account. The letter P stands for afternoon and A for morning. If the value for P-A is positive, it shows that the difference in elevation between the two bench marks is greater by the afternoon than by the morning leveling. The values for the sections which have both runnings made at the same time of the day are given for purposes of comparison with those sections run both in the morning and the after- noon. Only the average value without regard to sign can be given for the A-A and P-P sections. 1 On this and the following pages, the grades are named by the difference in elevation of the two ends of the separate sections. As the average length of these sections is roughly about 1 kilometer, a grade of 10 meters as given here corresponds approximately to a 1 per cent grade. PRECISE LEVELING, BRIGHAM 10 SAN FRANCISCO. Table 1. SECTIONS WITH GRADE EXCEEDING 10 METERS PER SECTION. 35 San Fran- cisco to Marmol. Beowawe to Marmol. Brigham to Beowawe. Butte to Devon. Pocatello to Butte. All lines. 64 +135.3 + 2.11 65 -131.0 - 2.02 129 2.06 + 4.3 + 0.03 75 166.4 2.22 None. 53 +136.0 + 2.67 24 - 62.0 - 2.17 77 2.44 + 84.0 + 1.09 26 51.5 1.98 37 +103.8 + 2.81 28 - 67.6 - 2.41 62 2.76 + 36.2 + 0.68 53 146.8 2.77 34 +121.3 + 3.57 24 - 82.2 - 3.42 61 3.34 + 39.1 + 0.64 49 112.6 2.30 188 +496.4 + 2.04 144 -340. 4 - 2.36 332 2.52 +156.0 + 0.47 205 480.4 2.34 3 -7.6 -2.63 3 2.5 -7.6 -2.53 2 3.1 1.6 8ECTIONS "WITH GRADE LESS THAN 10 METERS PER SECTION. 160 +336. 1 + 2.10 102 -171.3 - 1.68 262 1.94 +164.8 + 0.63 144 275.8 1.92 174 +321.9 + 1.85 164 -301.6 - 1.84 338 1.84 + 20.4 + 0.08 168 299.4 1.78 193 +431.9 + 2.24 166 -303.6 - 1.95 349 2.11 +128.3 + 0.37 135 266.1 1.97 160 +314.3 + 1.96 137 -307.1 - 2.24 297 2.09 + 7.2 + 0.02 131 304.4 2.32 74 +240.9 + 3.26 70 -194.3 - 2.78 144 3.02 + 46.6 + 0.32 124 328.9 2.65 761 +1645. 1 + 2.16 629 -1277.8 - 2.03 1390 2.10 + 367.3 + 0.26 702 1474.6 2 10 A-A and P-P, total ALL SECTIONS. 224 +471.4 + 2.10 167 -302. 3 - 1.81 391 1.98 +169. 1 + 0.43 219 442.2 2.02 174 +321.9 + 1.85 167 -309.1 - 1.86 341 1.85 + 12.8 + 0.04 170 302.5 1.78 246 +567.9 + 2.31 180 -355.6 - 1.98 426 2.17 +212.3 + 0.60 161 317.6 1.97 194 +418. 1 + 2.16 166 -374.7 - 2.27 369 2.21 + 85.7 + 0.24 184 451.2 2.45 111 +362. 2 + 3.26 94 -276.5 - 2.94 205 3.12 + 43.4 + 0.21 173 441.5 2.55 949 +2141.5 + 2.25 773 -1618.2 - 2.09 1722 2.18 + 523.3 + 0.30 907 1955.0 2.16 A-A and P-P, total As stated above there is no standard length of sight and therefore the sizes of the mean differences without regard to sign between the two runnings for the sections of different grade may have little significance, but with the sign considered the size and the sign of the differences of P-A are of great importance in indicating whether there may be systematic errors present. For the steep sections positive values of P-A predominate, there being 188 positive and 144 negative. Four of the five fines of levels have the positive sign for the total accumulated dis- crepancy and the mean accumulated discrepancy per section varies from + 0.03 to + 1 .09 milli- meters. The line which gives a negative value has only 3 sections with one running in the morning and the other in the afternoon and may be disregarded. The mean accumulated dis- crepancy per section for all the lines combined is +0.47 millimeter. Even the sections with grades less than 10 meters show a positive mean accumulated discrepancy for each line with an average accumulated discrepancy of +0.26 for all the five lines taken together. This value is only 55 per cent as great as the values for the steep sections. On the steep sections the mean difference without regard to sign for the P-A sections is 2.52 millimeters, while it is 2.34 millimeters for the mean of the P-P and A-A sections. This shows 36 U. S. COAST AND GEODETIC SURVEY SPECIAL PUBLICATION NO. 22. a closer agreement between the differences in elevation obtained by two runnings at the same time of day than at different times. There is no such difference in the mean values for those sections with low grades. Taken as a whole, the 1722 P-A sections indicate that on an average the afternoon running will give a greater difference in elevation between two bench marks than will the morning running. This average value for P-A is +0.30 millimeter for bench marks averaging about 1.0 kilometer apart. On page 20 of the Fourth General Adjustment of the Precise Level Net in the United States it is stated that there probably is a systematic difference between the morning and afternoon runnings of a section on steep slopes. The following paragraph on the subject is quoted from that report : There is a possibility of an accumulated discrepancy being produced by refraction on lines having steep grades. If the conditions in regard to refraction be the same on the two runnings of a line, there would be no divergence from that cause ; but it is probable that the refraction is different on the higher sight than the lower one and that this difference changes during the day as the relative temperatures of the ground and air vary. The refraction on the higher sight (up the slope) is no doubt different in the morning with a rising temperature from what it is in the afternoon with a falling temperature, while the lower sight (down the slope) which comes well above the surface of the ground will not vary so much between the forenoon and afternoon. Consequently, if the observer systematically leveled forward early in the day and backward late in the day, refraction might cause an accumulated discrepancy. If it does, there should be a change of sign in the discrepancy when the program is reversed by leveling backward in the morning and forward in the afternoon. Also, without a change of program a change of sign should occur after passing a summit or the lowest point in a valley. It is the author's opinion that the afternoon running gives on an average a difference which is closer to the truth than the morning running. In the afternoon the temperatures of the ground and the air are more nearly the same and a layer of air of uniform density should be concentric or nearly so with the sea-level surface. If this is true the refraction on the front and back sights should be about the same. The leveling of the United States Coast and Geodetic Survey is seldom done after 5 o'clock in the afternoon. So the afternoon running is not materially affected by the abnormal refraction of the late afternoon when a line of sight on a grade would pass through layers of colder and denser air which would tend to be concentric with the surface of the ground. In the late afternoon the earth cools more rapidly than the air and the air near the earth's surface becomes colder than the air above and consequently denser than normal. In the morning on a clear day the air is receiving heat from the earth's surface. This decreases the density of the air close to the ground, which forms layers which tend to be con- centric with the surface of the ground rather than with the sea-level surface. (The air near the earth is of course not at rest but tends to rise, owing to the decreased density.) It may be assumed that the line of sight to the observer from the rod held down the grade is not affected abnormally while the sight to the rod held up the grade is usually close to the ground and must pass through the layers of decreased density near the earth's surface. This sight would be less refracted than the one down the grade and therefore the morning running would give too small a difference between the zeros of the rods sighted on from one station. It is the writer's belief that, other things being equal, a line of levels run over steep grades in two directions in the after- noon, from noon to about one hour before sundown, will give results closer to the truth than levels with both runnings in the forenoon or with one leveling in the forenoon and the other in the afternoon. It is believed that this also applies to leveling over slopes of moderate grade. The following table is similar to the one shown above, except that the data are given for only those sections which had both runnings in the sunshine: PBECISE LEVELING, BKIGHAM TO SAN FBANCISCO. 37 Table t. SECTIONS WITH GRADE EXCEEDING 10 METERS PER SECTION. Number of sections . . P-A, total, positive. Mean discrepancy . . . Number of sections . . P-A , total, negative . Mean discrepancy. . . Number of sections Mean discrepancy Accumulated discrepancy Mean accumulation per section. Number of sections . . A-A and P-P, total. Mean discrepancy . . . San Fran- cisco to Marmol. 31 + 67.6 + 2.18 28 - 58.2 - 2.08 59 2.13 + 9.4 + 0.16 27 62.6 2.32 Beowawe to Marmol. None. 3 7.6 2.5 3 2.5 7.6 2.6 2 3.1 1.6 Brigham to Beowawe. 46 +110.3 + 2.40 20 - 40.9 - 2.04 66 2.29 + 69.4 + 1.05 20 39.7 1.98 Butte to Devon. 22 + 76.0 + 3.45 18 - 43.8 - 2.43 40 3.00 + 32.2 + 0.80 35 99.0 2.83 Pocatello to Butte. 32 + 104.7 + 3.27 18 - 52.5 - 2.92 50 3.14 + 52.2 + 1.04 43 91.1 2.12 All lines. 131 + 358.6 + 2.74 87 -203.0 - 2.33 218 2.58 + 155.6 + 0.71 127 295.5 2.33 SECTIONS WITH GRADE LESS THAN 10 METERS PER SECTION. Number of sections . . P-A, total, positive. Mean discrepancy . . . Number of sections . . P-A , total, negative . Mean discrepancy . . . Number of sections Mean discrepancy Accumulated discrepancy Mean accumulation per section . Number of sections . . A-A and P-P, total. Mean discrepancy . . . 100 +202.9 + 2.03 57 -106.0 - 1.86 157 1.97 + 96.9 + 0.62 64 104.2 1.63 134 + 249.4 + 1.86 119 -206.1 - 1.73 253 1.80 + 43.3 + 0.17 168 299.4 1.78 116 +253.5 + 2.18 110 -200.9 - 1.83 226 2.01 + 52.6 + 0.23 141 277.9 1.97 121 +248. 4 + 2.05 111 -261.5 - 2.36 232 2.19 - 13.1 - 0.06 95 221.4 2.33 58 + 186.6 +3.22 59 -161.0 - 2.73 117 2.97 + 25.6 + 0.22 102 2S9.5 2.84 529 + 1140.8 + 2.15 456 - 935.5 - 2.05 985 2.11 +205.3 + 0.21 570 1192. 4 2.09 ALL SECTIONS. Number of sections . . P-A, total, positive . Mean discrepancy . . . Number of sections . . P-A, total, negative. Mean discrepancy . . . Number of sections Mean discrepancy Accumulated discrepancy Mean accumulation per seetion . Number of sections . . A-A and P-P, total. Mean discrepancy . . . 131 +270.5 + 2.06 134 +249.4 + 1.86 162 +363.8 + 2.25 143 +324.4 + 2.27 90 +291.3 + 3.24 660 +1499. 4 + 2.27 85 -164.2 - 1.93 122 -213.7 - 1.75 130 -241.8 - 1.86 129 -305.3 - 2.37 77 -213.5 - 2.77 543 -1138.5 - 2. 10 216 2.01 +106.3 + 0.49 256 1.81 + 35.7 + 0.14 292 2.07 + 122.0 + 0.42 272 2.32 + 19.1 + 0.07 167 3.02 + 77.8 + 0.47 1203 2.19 + 360.9 + 0.30 91 166.8 1 83 170 302.5 1.78 161 317.6 1.97 130 320.4 2.46 145 380.6 2.62 697 1487.9 2.14 As before, the afternoon runnings give on an average greater differences in elevation be- tween the ends of sections than the morning runnings. But on steep grades the all-sunshine results give a mean accumulated discrepancy of P-A of +0.71 millimeter per section while the value was only + 0.47 millimeter where no account was taken of clear or cloudy weather. This seems to bear out the theory stated above that the afternoon runnings give results closer to the truth than the morning runnings. If it were cloudy in the morning the difference between the morning and afternoon results should agree more closely than if the morning running were in sunshine. The data for the sections having low grades indicate the same results for the all-sunshine runnings as for the runnings with sunshine or clouds disregarded. RELATION BETWEEN ERRORS OF LEVELING AND CLEAR AND CLOUDY SKY. The following table gives data for the leveling done under different conditions of the sky and also for the sections which have both runnings in sunshine or both in cloudy weather. The sections are again divided into two groups according to their grades. First, those for which the difference in elevation of their ends exceeds 10 meters and, second, those with differ- ences less than 1 meters. 38 U. S. COAST AND GEODETIC SUBVEY SPECIAL PUBLICATION NO. 22. As was stated on page 34, it is difficult or impossible to notice any relations between the accidental errors and the weather conditions, as there is no fixed length of sight. But the data in the tables given below should indicate whether there are any relations between systematic errors and the degree of clearness of the sky. The letter " C " stands for clouds and " S " f or sun- shine or clear. Table 3. SECTIONS WITH GRADE EXCEEDING 10 METERS PER SECTION. San Fran- cisco to Marmol. Beowawe to Marmol. Brigham to Beowawe. Butte to Devon. Pocatello to Butte. All lines. 28 + 54.6 + 1.95 28 - 53.9 - 1.92 56 1.94 + 0.7 + 0.01 55 101.9 1.85 93 207.7 2.23 None. 8 + 30.7 + 3.84 4 - 4.7 - 1.18 12 2.95 + 26.0 + 2.17 10 27.6 2.76 36 69.5 1.93 10 + 23.4 + 2.34 6 - 9.2 - 1.53 16 2.04 + 14.2 + 0.89 15 33.1 2.21 60 169.0 2.82 10 + 50.5 + 5.05 7 - 17.3 - 2.47 17 3.99 + 33.2 + 1.95 None. 56 +159. 2 + 2.84 45 - 85.1 - 1.89 101 2.42 + 74.1 + 0.73 80 162.6 2.03 285 702.1 2.46 None. None. None. C-C, total 3 7.6 2.53 93 248.3 2.67 S-S, total SECTIONS WITH GRADE LESS THAN 10 METERS PER SECTION. Number of sections. C-S, total, positive. Mean discrepancy. . Number oi sections . C-S, total, negative. Mean discrepancy . . Number of sections Mean discrepancy Accumulated discrepancy Mean accumulation per section . Number of sections. C-C, total Mean discrepancy . . Number of sections . S-S, total Mean discrepancy . . 46 + 83.6 + 1.82 74 -160.6 - 2.17 120 2.04 - 77.0 - 0.64 56 96.2 1.72 240 45S.9 1.91 58 + 134.4 + 2.32 55 - 92.1 - 1.68 113 2.00 + 42.3 + 0.37 39 56.1 1.44 362 646.2 1.78 +160.6 + 2.33 62 -137.3 - 2.21 131 2.27 23.3 0.18 51 95.6 1.87 347 695.8 2.00 24 + 40.4 + 1.68 24 - 51.4 - 2.14 48 1.91 - 11.0 -0.23 46 88.4 1.92 290 635.7 2.19 20 + 54.1 + 2.70 13 - 40.9 - 3.15 33 2.88 + 13.2 + 0.40 12 29.8 2.48 220 626.9 2.85 217 +473. 1 + 2.18 228 -4S2.3 - 2.12 445 2.15 -9.2 - 0.02 204 366.1 1.79 1459 3063. 5 2.10 ALL SECTIONS. Number of sections . C-S, total, positive. . Mean discrepancy . . . Number of sections . C-S, total, negative. Mean discrepancy . . , Number of sections Mean discrepancy Accumulated discrepancy Mean accumulation per section . Number of sections. C-C, total Mean discrepancy . . Number of sections. S-S, total Mean discrepancy. . 74 +138. 2 + 1.87 102 -214.5 - 2.10 176 2.00 - 76.3 - 0.43 HI 198.1 1.78 333 666.6 2.00 58 +134.4 + 2.32 55 - 92.1 - 1.68 113 2.00 + 42.3 + 0.37 39 56.1 1.44 365 653.8 1.79 77 +191.3 + 2.48 -142.0 - 2.15 143 2.33 + 49.3 + 0.35 61 123.2 2.02 383 765.3 2.00 34 + 63.8 + 1.88 30 - 60.6 - 2.02 64 1.94 + 3.2 + 0.05 61 121.5 1.99 350 804.7 2.30 30 + 104.6 + 3.49 20 - 58.2 - 2.91 50 3.26 +46.4 + 0.93 12 29.8 2.48 313 875.2 2.80 273 +632.3 + 2.32 273 -567.4 - 7.08 546 2.20 + 64.9 + 0.12 284 528.7 1.86 1744 3765.6 2.16 In each of the lines considered the running of a section with steep grade, when the sky was cloudy, gave on an average a difference in elevation greater than the running when the sky was clear. There are 101 sections of steep slopes or grades on which the two runnings of a section were made, one in sunshine and the other with a cloudy sky. The mean accumulated discrep- ancy is + 0.73 millimeter. PRECISE LEVELING, BRIGHAM TO SAN FRANCISCO. 39 There seems to be no tendency toward an accumulation of C-S (cloudy minus sunshine) for those sections having grades less than 10 meters per section. The total discrepancy with regard to sign for 445 such sections is only —9.2 millimeters or —0.02 millimeter per section. It is the general belief among geodesists that the leveling under a cloudy sky is practically free from systematic errors resulting from atmospheric conditions. Therefore it would appear that the leveling under a clear sky causes the observed differences in elevation on steep grades to be too small. In the following table are given data for the steep sections which had one running in clear and the other in cloudy weather, but the data are arranged in two groups, one where the run- ning in sunshine was made in the morning called (S A), while the other has the running in sun- shine made in the afternoon (S P) : Table 4- SECTIONS WITB GRADE EXCEEDING 10 METERS PER SECTION. San Fran- cisco to Marmol. B to Marmol. Brigham to Boowawe. Butte to Devon. Pocatello to Butte. All lines. Number of sections . . . C-SA, total, positive. Number of sections . . . C-SA, total, negative. Number of sections . . . C-SP, total, positive. . Number of sections . . . C-SP, total, negative. C-S A , accumulation per section. C-SP, accumulation per section. 13 +22.3 21 -44.8 IS +32.3 7 - 9.1 - 0.68 + 1.05 6 +25.2 3 - 3.7 2 + 5.5 1 - 1.0 + 2.39 + 1.50 3 - 5.J 7 + 16.5 3 3.4 + 0.18 + 1.31 4 +20.4 3 7.0 +30.1 4 -10.3 + 1.91 + 1.98 28 +74.8 30 -61.3 30 +84.4 15 -23.8 + 0.24 + 1.34 SECTION'S WITH GRADE LESS THAN 10 METERS PER SECTION. Number of sections . . . C-SA, total, positive . Number of sections . . . C-SA, total, negative. Number of sections . . . C-SP, total, positive.. Number of sections . . . C-SP, total, negative. C-SA, accumulation per section . C-SP, accumulation per section . 24 + 42.4 22 +41.2 41 -93.7 0.43 0.83 24 +55.6 33 -57.3 34 +78.8 22 -34.8 - 0.03 + 0.79 44 + 109.9 25 + 50.7 33 87.6 + 0.69 - 0.64 13 +20.8 13 -24.1 11 +19.4 11 -27.3 - 0.13 - 0.36 19 +29.1 -23.6 11 +25.0 5 -17.3 + 0.18 + 0.48 124 +257.8 116 -231.6 +215. 1 112 -260.7 0.11 0.21 ALL SECTIONS. Number of sections C-SA, accumulation per section. Number of sections C-SP, accumulation per section. 91 - 0.52 85 - 0.34 57 -0.03 56 + 0.79 82 + 0.87 61 -0.53 32 - 0.07 32 + 0.16 34 + 0.56 26 + 1.06 296 + 0.13 260 + 0.06 In the above table it is shown that the cloudy running gave on an average a larger value for the difference in elevation on steep grades than the running in sunshine. If, as was stated above, it is assumed that the cloudy running is free from systematic error, then on an average the afternoon running in sunshine gave a smaller difference in elevation than the morning running in sunshine. Contrary to what might be expected from the data in a previous table, the value of C-SA for one of the lines is negative. All of the other values for C-SA are positive, as is the case with the values of C-SP. The average accumulated values of C-SA and C-SP for the sections with low grade are small, +0.11 nrillimeter per section in the former and —0.21 millimeter per section in the latter. These sections are quite numerous as compared with the number of steep sections, and should no doubt be given some consideration before coming to a decision as to whether the morning or afternoon runnings in sunshine give the larger differences. 40 U. S. COASI AND GEODETIC SUBVEY SPECIAL PUBLICATION NO. 22. The third section of the above table gives the average accumulated discrepancy per section for 296 (C-SA) and for 260 (C-SP) sections, without regarding the amount of the grade. The average (C-SA) value is +0.13 millimeter per section and the average (C-SP) value is only + 0.06 millimeter per section. This evidence is weak but it agrees with the conclusion expressed on page 36, that the afternoon running in sunshine gives a greater difference than a forenoon running in sunshine. The data in the following table were prepared with the view of investigating possible rela- tions between the systematic errors in leveling and the wind and calm during the observations. In the table C stands for calm and W for wind. The strength of the wind, whether strong, moderate, or light, is not considered. Table 5. SECTIONS WITH GRADE EXCEEDING 10 METERS PER SECTION. Number of sections . . C-W, total, positive. Mean discrepancy . . . Number of sections. . C-W, total, negative. Mean discrepancy Number of sections Mean discrepancy Accumulated discrepancy Mean accumulation per section . Number of sections . C-C, total Mean discrepancy . . Number of sections . W-W, total Mean discrepancy . . San Fran- cisco to Marmol. 20 +41.2 + 2.06 25 -56.1 - 2.24 45 2.16 -14.9 - 0.33 129 262.6 2.04 28 62.6 2.24 Beowawe to Marmol. 1 +2.7 +2.7 None. 1 2.7 +2.7 +2.7 4 8.0 2.0 None. Brigham to Beowawe. 12 +22.6 + 1.88 21 -53.2 - 2.53 33 2.30 -30.6 - 0.93 10 10.6 1.06 64 159.7 2.49 Butte to Devon. +25.9 + 2.88 14 -34. 4 - 2.46 23 2.62 - 8.5 - 0.37 62 164.5 2.65 31 96.1 3.10 Pocatello to Butte. 21 +47.6 + 2.27 15 -56.1 - 3.74 2.88 - 8.5 - 0.24 31 91.6 2.95 57 167.1 2.93 All lines. 63 +140.0 + 2.22 75 -199.8 - 2.66 138 2.46 - 59.8 - 0.43 236 537.3 2.28 180 485.5 2.70 SECTIONS WITH GRADE LESS THAN 10 METERS PER SECTION. linve.. Number of secti C-W, total, posil Mean discrepancy Nu mber of sections .. . C-W, total, negative. . Mean discrepancy Number of sections Mean discrepancy Accumulated discrepancy Mean accumulation per section . Number of sections . C-C, total Mean discrepancy . . Number of sections . W-W, total Mean discrepancy . . 46 + 74.6 + 1.62 74 -155.9 -2.11 120 1.92 - 81.3 - 0.68 151 265.3 1.76 134 261.7 1.95 81 +140.5 + 1.73 82 -149. 3 -1.82 163 1.78 - 8.8 - 0.05 195 369.5 148 256.8 1.74 64 +136.6 + 2.14 93 -221.0 - 2.38 157 2.28 -84.4 - 0.54 134 259.4 1.94 193 390.6 2.02 50 +111.4 + 2.23 60 -116.9 - 1.95 110 2.08 -5.5 - 0.05 245 533.6 2.18 85 173.5 2.04 36 + 91.2 + 2.53 36 -114.3 - 3.18 72 2.85 - 23.1 - 0.32 113 302.6 2.68 83 259.8 3.13 277 +554.3 + 2.00 345 -757. 4 - 2.20 622 2.11 -203.1 - 0.33 1,730.4 2.06 643 1,342.4 2.09 ALL SECTIONS. Number of sections . . C-W, total, positive. Mean discrepancy . . . Number of sections . . C-W, total, negative.. Mean discrepancy Number of sections Mean discrepancy Accumulated discrepancy Mean accumulation per section . Number of sections . C-C, total Mean discrepancy . . Number of sections. W-W, total Mean discrepancy . . 66 +115.8 + 1.75 -212.0 - 2.14 165 1.99 - 96.2 - 0.58 280 527.9 1.89 162 324.3 2.00 82 + 143.2 + 1.75 -149. 3 - 1.82 164 1.78 - 6.1 - 0.04 199 377.5 1.90 148 256.8 1.74 + 159.2 + 2.10 114 -274.2 -2.41 190 2.28 -115.0 - 0.61 144 270.0 1.88 257 550.3 2.14 +137.3 + 2.33 74 -151. 3 - 2.04 133 2.17 - 14.0 -an 307 698.1 2.27 116 269.6 2.32 57 +138.8 + 2.44 51 -170. 4 - 3.34 108 2.86 - 31.6 - 0.29 144 394.2 2.74 140 426.9 3.05 340 +694. 3 + 2.04 420 -957.2 - 2.28 760 2.17 -262.9 - 0.35 1,074 2,267.7 2.11 823 1,827.9 2.22 PRECISE LEVELING, BBIGHAM TO SAN FRANCISCO. 41 The sections are again divided into two classes, first those having differences in elevation between the ends of more than 10 meters, and second those sections having a difference in eleva- tion of less than 10 meters. The above table shows that each of the groups of sections has a minus sign for the accumulated value of (C-W), calm minus wind. (There is only one steep section for the second line.) For the steep sections, 138 in number, the accumulated value per section is —0.43 millimeter. On the low-grade sections the mean value of the accumulated discrepancy is —0.33 millimeter per section. The mean value for all sections regardless of the grade is —0.35 millimeter per section. These facts show that the running in wind gave a greater difference in elevation than a running during calm. The conclusion that this is a general rule might not be justified for other factors enter the case. All of the lines are in the western portion of the United States where it is usually more windy in the afternoon than in the morning. Calm is infrequent there in the afternoon. Therefore the value of C-W would be somewhat confused with the value of P-A. If both runnings are made in the forenoon or both in the afternoon, then the values of C-W should be practically free from the effect of the time of day. In the following table there are given the data for such sections the amount of grade not being considered : Table 8. ONLY SUCH SECTIONS AS HAVE RUNNINGS IN BOTH DIRECTIONS EITHER IN THE MORNING OR IN THE AFTERNOON. San Fran- cisco to Marmol. Beowawe to Marmol. Brigham to Beowawe. Butte to Devon. Pocatello to Butte. AH lines. Number of sections C-W, total, positive Mean discrepancy Number of sections C-W, total negative Mean discrepancy Number of sections Accumulated discrepancy Mean accumulation per section 20 +32.7 + 1.64 27 -68.3 - 2.53 47 -35.6 - 0.76 16 +35.6 + 2.22 20 -40.9 - 2.04 36 - 5.3 - 0.15 16 +22.4 + 1.40 12 -29.6 - 2.47 28 - 7.2 - 0.26 14 +42.4 + 3.03 13 -29.2 - 2.25 27 + 13.2 + 0.49 19 +44.1 + 2.32 18 -54.3 - 3.02 37 -10.2 - 0.28 85 +177.2 + 2.08 90 -222.3 - 2.47 175 - 45.1 - 0.26 The value of C-W in the above table is practically free from the effect of the time of day and also that of cloudy or clear weather. It appears then that the mean accumulated value of C-W is —0.26 millimeters per section. This makes the difference in elevation obtained from the running in wind greater than the difference obtained in calm. There are no data collected as to whether the size of C-W is a function of the steepness of the grade. There are 495 sections, each of which had one running in the morning and one running in the afternoon with both runnings made during calm. These sections should have values for P-A which are free from the effect of calm and wind. The data for these sections are shown below: Table 7. ONLY SUCH SECTIONS AS WERE RUN IN BOTH DIRECTIONS DURING CALM. San Fran- cisco to Marmol. Beowawe to Marmol. Brigham to Beowawe. Butte to Devon. Pocatello to Butte. All lines. 88 +177.6 + 2.02 69 -122.1 - 1.77 157 + 55.5 + 0.35 55 +112.0 + 2.04 62 -119.7 - 1.93 117 - 7.7 - 0.07 44 +73.0 + 1.66 43 -75.6 - 1.76 87 - 2.6 - 0.03 33 +119.4 + 3.62 29 - 86.6 - 2.98 62 + 32.9 + 0.53 39 +121.5 + 3.12 33 - 93.6 - 2.84 72 + 27.9 + 0.39 259 +603.5 + 2.33 236 -497. 5 - 2.11 495 +106.0 + 0.21 42 U. S. COAST AND GEODETIC SURVEY SPECIAL PUBLICATION NO. 22. The above values for the accumulated discrepancy P-A are no doubt somewhat affected by cloudy and clear weather, for in general the forenoons are somewhat more free from clouds than the afternoons, but it is believed that this effect is small. The value of P-A for the accumu- lated discrepancy is +0.22 millimeter per section. The afternoon running gives a larger value for the difference in elevation between the ends of a section than the morning running. The steepness of the grade has not been considered as there were so few P-A sections on steep grades which were run only in calm weather. But it is worthy of note that the three lines, the first, fourth, and fifth, which have the greatest mean grade per section (see p. 34), have the largest values of P-A (both in calm). The second and third lines have accumulated values of the discrepancy of C-W of only —0.07 and —0.03 millimeter. Therefore the conclusion may be drawn that the size of P-A, free from the effects of calm or wind, is a function of the grade. If it is assumed that the running in wind is free from error, then the data for the sections shown below should give an indication as to whether an afternoon or forenoon running of a sec- tion will give the greater difference in elevation. mm. Number cf sections 256, total positive value (C-W) A + 499.2 Number of sections 330, total negative value (C-W) A — 759.0 Number of sections 94, total positive value (C-W) P +221.7 Number of sections 87, total negative value (C-W) P — 182.3 Mean accumulated discrepancy per section (C-W) A — 0.44 for (C-W) P + 0.22 The term (C-W) A represents calm minus wind, with the calm running in the forenoon, while (C-W) P is the same, except that the calm running is in the afternoon. The indications in the above table are that the difference in elevation from the calm running in the forenoon is too small and from the calm running in the afternoon too great. This bears out the conclusion stated on page 36 that the afternoon running gave a greater difference than the forenoon running. RELATION BETWEEN THE ERRORS OF LEVELING AND THE FORWARD AND BACKWARD RUNNINGS OF A LINE. The values of B-F in the following table represent the difference in elevation between the ends of the sections as given by the two runnings, one forward and one backward. When the section is up grade in the line of progress the difference between the two runnings B-F is posi- tive if the backward running gives a greater difference between the two ends than the forward running. The value is negative if the forward running gives the greater difference. If the section is down grade in the line of progress the value of B-F is positive, if the back- ward running gives the smaller difference in elevation between the ends of the section, and is negative when it gives the larger difference. In general B-F is positive if the backward running gives the higher elevation a,bove sea level for the bench mark at the forward end of the section. In the following table are given data regarding the accumulated value of B-F for the five fines considered in this investigation. PEECISE LEVELING, BKIGHAM TO SAN FRANCISCO. Table 8. SECTIONS WITH GRADE EXCEEDING 10 METERS PER SECTION. 48 San Fran- cisco to Marmol. Beowawe to Marmol. Brigham to Beowawe. Butte to Devon. Pocatello to Butte. AUllnes. 100 +207.8 + 2.08 100 -220.1 - 2.20 200 2.14 - 12.3 - 0.06 2 +3.1 +1.6 3 -7.6 -2.5 5 2.14 -4.5 -0.9 60 +145.3 + 2.42 45 -103.2 - 2.29 105 2.37 + 42.1 + 0.40 72 +248.3 + 3.45 43 - 85.7 „- 1.99 115 2.90 +162.6 + 1.41 66 +188.3 + 2.86 42 -125.3 - 2.98 108 2.90 + 63.0 + 0.68 300 +792.8 + 2.64 233 -541. 9 - 2.33 533 2.50 +250.9 + 0.47 SECTIONS WITH GRADE LESS THAN 10 METERS PER SECTION. Number of sections . . B-F, total, positive.. Mean discrepancy . . . Number of sections . . B-F, total, negative. Mean discrepancy . . . Number of sections Mean discrepancy Accumulated discrepancy Mean accumulation per section . 186 +356.8 + 1.92 222 -429.5 - 1.93 408 1.93 - 72.7 - 0.18 251 +460.1 + 1.83 254 -453.2 - 1.78 505 1.81 + 6.9 + 0.01 240 +520.1 + 2.17 242 -480.8 - 1.99 482 2.08 + 39.3 + 0.08 231 +501.4 + 2.17 217 -457.5 - 2.11 448 2.14 + 43.9 + 0.10 124 +374.2 + 3.02 145 -397.3 - 2.74 2.87 23.1 0.09 1032 +2212. 6 + 2.14 1080 -2218.3 - 2.05 2112 2.09 - 5.7 0.00 The large accumulations occurred on steep grades, though the evidence is not conclusive that this accumulation is of the same sign. Of the five fines, the one from Beowawe to Marmol should be ignored, for it has only five sections with steep grades. Of the other four lines, one has an accumulated value of —0.06 millimeter per section for B-F, while the other three have ac- cumulated values ranging from +0.40 to +1.41 millimeters. The mean of all steep sections for the five lines is +0.47 millimeter. This indicates a large systematic error on steep grades. The remainder of the sections which have low grades show no systematic error in the accumulated values of B-F. Two of the values are negative and three positive, while the largest one is —0.18 millimeter and the mean for the 2112 sections of all lines is 0.00 millimeter. The program followed by the observers seems to avoid troublesome accumulation of error on low grades, but not so on the steep grades. The difference between the two runnings of a line can not alone disclose any systematic errors due to the azimuth of the fine, for there would be no systematic effect from that cause on one running which should not be present on the other. There may possibly be a systematic error which is a function of the azimuth of the fine, but this would be shown only by tho errors of closure of the loops. CONCLUSIONS. The above discussion (pp. 32 to 43) seems to make justifiable the following conclusions: 1. The average size of the discrepancy between the difference in elevation determined twice under different conditions does not give a clear idea of the magnitude of the accidental errors which may be produced by certain conditions, as the custom is to make the length of sight as great as the conditions will permit. Therefore the extra length of sight may offset otherwise favorable conditions and give a large difference between two runnings of a section. 2. For sections run twice under different conditions the average accumulated value of the discrepancy is greater for the sections with steep grades than with low grades, the direction of the running being ignored and only the actual difference in elevation between the ends of a section being considered. 44 U. S. COAST AND GEODETIC SURVEY SPECIAL PUBLICATION NO. 22. 3. On all grades, but more especially the steep ones, the difference in elevation determined in the afternoon is on an average greater than that determined in the forenoon. 4. On an average, a running during wind gives a greater difference in elevation than one during calm. The amount of this difference is somewhat greater for the steep than for the low grades. 5. On an average a running when the sky is cloudy gives a larger difference in elevation between two points, on a steep grade, than a running while the sun is shining. For low grades there is practically no difference, on an average, between the runnings under the two conditions. 6. On steep grades the average accumulated value of the backward minus the forward (B-F) running is positive. There is no accumulation for the low sections considered as one group. 7. For steep grades (about 10 meters per kilometer) the probability is that the afternoon running gives, on an average, a result closer to the truth than the forenoon ru nnin g. The afternoon running should be ended sometime before sundown. The running in wind probably gives results on an average closer to the truth than a running in calm. While the data in the tables make the above conclusions justifiable, yet, owing to the fact that there are so many conditions to be considered, it is impracticable to obtain at present any reliable numerical values for the effect of any given atmospheric condition or set of conditions. It is believed that, other things being equal, the running in the afternoon (if not within about an hour of sunset) gives, on an average, more accurate results than the forenoon running; also that, other things being equal, a running in wind is more accurate, on an average, than one in calm • and, other things being equal, a running with a cloudy sky will be more accurate, on an aver*e, than one in sunshine. Hence, the ideal condition would be an afternoon with a moderate wind and a cloudy sky. It is believed that the mere fact of running backward or forward has no real effect on the result of a running, as the value of B-F may vary in sign for different lines and even for different parts of a single line. As data accumulate it may be possible to determine accurately the effect of certain weather conditions and a correction might then be applied to the leveling. With our present knowledge it seems safe to follow such a program as that now used in the United States Coast and Geodetic Survey. On level ground or ground with low grades the observer need not be so particular in regard to the relation between the weather conditions and the separate runnings provided the two runnings of a section are made on different days, to meet the requirements of the Inter- national Geodetic Association; but on a steep slope it is best not to make obseivations in the early morning or the late afternoon; the reading of a wire on the rod should never be less than about two decimeters; and whenever part of a day must be taken for setting bench marks or computing, the forenoon should be used for that work and the afternoon for leveling, rather than the reverse. As was stated on page 22 of Special Publication No. 18, it is not believed that the accu- mulated value of B-F (backward minus forward) gives any accurate indication of the systematic error which may be expected in a line of levels. Let it be assumed that on an average the afternoon running gives a greater difference in elevation than the forenoon running. Then, if the line is on a long steep grade, the accumulated value of B-F may be very small if each section has the two runnings in the forenoon or both in the afternoon, while the accumulated value of B-F will probably be large if all of one running is made in the forenoon and all of the other running is made in the afternoon. In each case the actual accumulated systematic error would be the same. PRECISE LEVELING, BBIGHAM TO SAN FRANCISCO. STANDARD ELEVATIONS. 45 The following list gives the standard elevation, in meters and feet above mean sea level, of each bench mark on the precise level line Brigham, Utah, to San Francisco, Cal. Elevations of permanent bench marks. Place. Brigham, Utah Do Do Honey ville, Utah Dewey, Utah Near Corinne, Utah... Corinne, Utah Near Corinne, Utah Near Balfour, Utah Balfour, Utah Near Hansen, Utah. . . Hansen, Utah Near Hansen, Utah . . . Blue Creek, Utah Near Blue Creek, Utah Kolmar, Utah Surbon, Utah Promontory, Utah Near Promontory, Utah Do Rozel, Utah Near Rozel, Utah. . . Near Lake, Utah Lake, Utah Near Lake, Utah Monument, Utah.... Near Monument, Utah. Do Near Kel ton, Utah.... Kelton Utah Near Kelton, Utah Near Peplin, Utah Ombey , Utah Near Romola, Utah . . . Do Near Terrace, Utah Terrace, Utah Near Terrace, Utah.... Bovine, Utah Near Bovine, Utah Near Umbria Junction, Utah. Lucin, Utah Near Umbria Junction, Utah. Do Do Gartney, Utah Near Tecoma, Nev Tecoma, Nev Near Tecoma, Nev Do Akbar, Nev Near Montello, Nev. . . Montello, Nev Do Banvard, Nev Noble, Nev UUin.Nev Wright.Nev Lo ray, Nev Omar, Nev Cobre, Nev Do Near Cobre, Nev Valley Pass, Nev Near Valley Pass, Nev. . Icarus, Nev Near Icarus, Nev.... Pequop, Nev Fenelon, Nev Near Holborn, Nev. Holborn,Nev Anthony, Nev Moor, Nev Cedar.Nev Kaw,Nev Near Wells, Nev. . . . Wells, Nev Do Near Wells, Nev Do Alazon, Nev Near Tulasco, Nev. . NearNardi, Nev Near Deeth , Nev Designation of bench mark. R... J,... K... L,... T... M„.. N,.. 0,... P„... Q»... R... S,... T„... U... V,... w... X,.. Y,.. z,... Aio. . B 10 .. Cio.. Die. Eio.. F l0 .. Gio.. Hio., Iio... Jio... Kio.. Lio.. M,... Nio.. Oi... Pi... Qi... Rio.. Sio. . T,... U,... V 10 .. 10- Y,.., Zio- . Au.. Ij... Jj... K,.. L,.. M... N,.. O,.. P... Qa„ R... S 3 ... T,.., U... V,.. w,.. X... Y... Z,.. A,.. B... C t ... D,.. E,_. F... Qt.. H... I,... J ( ... K,.. L... M... N... O... P,„ Q«~ R... S,... T,.., Standard elevation. Meters. 1309. 150 1313.399 1352.930 1301. 032 1317. 551 1287.547 1289.016 1290. 421 1293. 550 1294. 273 1289. 823 1290. 815 1295. 596 1301. 447 1323. 993 1333.590 1391. 661 1494. 255 1484. 824 1441.217 1400.062 1398.971 1325.579 1284. 236 1287. 202 1288.232 1292. 478 1287. 070 l_'sr,.oso 1286. 750 1326.236 1384. 143 1436.620 1404. 126 1400.376 1429.349 1387. 724 1357.271 1325.608 1339. 962 1350. 182 1362.878 1370. 114 1378.304 1387.348 1405.550 1457. 827 1467.322 1466.885 1469. 172 1471.488 1477. 112 1485. 769 1485. 765 1516. 712 1559. 786 1604.021 1649. 229 1705.966 1781.219 1805.230 1809.808 1831.050 1850. 212 1851. 795 1859. 244 1875. 226 1873. 173 1876. 107 1866. 993 1XCII.M7 1866. 4X5 1877. 788 1819. 671 1777. 134 1740. 174 1715. 462 1715.397 1711.902 1709. 278 1705. 310 1677. 398 1644. 437 1631.314 Feet. 4295. 103 4309.043 4438.738 4268. 469 4322. 605 4224. 227 4229. 047 4233.656 4243.922 4246.294 4231.694 4234. 949 4250.635 4269. 831 4343. 800 4375. 286 4565. 808 4902. 402 4871. 460 4728. 393 4593.370 4589. 791 4349.004 4213.364 4223.095 4226. 474 4240. 405 4222. 662 4219.414 4221.612 4351. 159 4541. 142 4713.311 4606.703 4594. 400 4689. 456 4552. 891 4452. 980 4349.394 4396. 192 4429.722 4471.376 4495. 116 4521.986 4551.658 46U.375 4782. 887 4814.039 4812. 605 4820. 108 4827. 707 4846. 158 4874. 560 4874.547 4976. 079 5117.398 6262. 526 5410. 845 5596.990 5843. 883 5922.659 5937. 678 6007. 370 6070. 237 6075. 431 6099.870 6152.304 6145. 568 6155. 194 6125. 293 6105. 030 6123. 626 6160. 709 5970. 037 5830. 480 5709. 221 5628. 145 5627. 932 5616. 465 5607.856 5594. 838 5503.263 5395. 124 5352. 069 Place. Deeth, Nev Natchez, Nev Halleck, Nev Elburz, Nev Near Elburz, Nev Ryndon, Nev Near Ryndon, Nev Osino, Nev Coin, Nev Near Elko, Nev Do Elkq.Nev Do Near Elko, Nev Near Avenel, Nev Avenel, Nev Near Avenel, Nev Near Moleen, Nev Moleen, Nev Near Moleen, Nev Near Tonka, Nev Tonka, Nev Near Tonka, Nev Near Vivian, Nev Vivian, Nev Carlin, Nev Near Carlin, Nev Tyrol,Nev Palisade, Nev Gerald, Nev Harney, Nev Cluro, Nev Beowawe, Nev Do... Do Ladoga, Nev Farrel, Nev Mosel, Nev Argenta, Nev Rosny, Nev Battle Mountain, Nev. Near Battle Mountain, Nev. Piute, Nev Mote, Nev Valmy, Nev Near Valmy Nev Stonehouse, Nev Herrin, Nev Iron Point, Nev Comus, Nev Near Preble, Nev Near Golconda, Nev Golconda, Nev Eglon, Nev Tule,Nev Winneraucca, Nev Benin, Nev Rose Creek, Nev Lamar, Nev Cosgrave, Nev Dodon.Nev MillCity.Nev Imlay , Nev Humboldt, Nev Valery, Nev Near Valery, Nev Near Rye Patch, Nev . Rye Patch, Nev Near Rye Patch, Nev. Near Zola, Nev Zola,Nev Oreana, Nev Woolsey, Nev Kodak, Nev Near Lovelocks, Nev.. Do Lovelocks, Nev Perth, Nev Granite Point, Nev Toulon, Nev Toy, Nev Miriam, Nev Near Huxley, Nev. . . . Parran, Nev Near Desert, Nev Designation of bench mark. U, V, Vm X, Y, Z At B. Cs D. E. F.(U.S.G.S.) G. H. I. J. K, L, M. N. O. P. Q. R. S. T. U. V. W, X, Y. Z. A, B C, o, H, I. J. K, u Mb N, O. P. Q. R. 8, T, U. v„ W,(S. P.).... x« Y, z 8 A, B, C, D, E, F 7 G, H, It h K,(S. P.) L 7 (S. P.) M*7 N,(S. P.) 0,(S. P.) Pi Qi R: S, T, U, V, w 7 X, Y, Z, A. Bs C, D,(S. P.) Standard elevation. Meters. 1626. 022 1614. 139 1594.771 1586.379 1580. 299 1572. 304 1570.662 1564. 760 1551. 898 1546. 867 1548. 173 1544. 382 1540. 855 1536. 418 1533. 332 1530. 494 1526. 957 1526. 558 1516. 769 1515. 674 1514. 198 1512. 654 1510. 640 1509. 118 1498. 672 1492. 558 1487. 450 1485. 169 1476. 289 1469. 163 1455. 204 1441.991 1432. 562 1432. 212 1430. 688 1420.740 1410.945 1397. 537 1388. 867 13S0. 447 1374. 690 1372.793 1373.358 1373. 594 1373. 821 1366. 276 1348. 853 1343. 121 1336. 901 1333.025 1333. 524 1327.004 1336. 950 1318. 108 1313. 059 1316.225 1310.059 1318. 017 1308. 160 1310. 824 1296.202 1287. 488 1278. 626 1290. 045 1304. 104 1294. 168 1295.933 1295. 850 1294. 190 1299.730 1289. 856 1267. 348 1249. 396 1220.988 1217. 142 1216. 350 1211. 967 1203. 666 1194. 333 1197.746 1197. 949 1194.025 1186. 403 1184. 441 1185. 857 Feet. 5334. 707 6295. 721 5232. 178 5204. 645 5184. 698 5158. 467 5153. 080 5133.717 5091.519 5075.013 5079.298 5066.860 5055.288 5040.731 5030. 607 5021.296 5009.691 5008. 382 4976. 266 4972. 674 4967. 831 4962. 766 4956. 158 4951. 165 4916. 893 4896.834 4880.075 4872. 592 4843. 458 4820. 079 4774.282 4730. 932 4699. 997 4698. 849 4693. 849 4661. 211 4629.075 4585.086 4556.641 4529.016 4510. 129 4503.905 4505. 759 4506. 533 4507. 278 4482.524 4425.362 4406.556 4386. 150 4373. 433 4375.070 4353.679 4386.310 4324. 493 4307.928 4318.315 429S. 085 4324. 194 4291. 855 4300. 595 4252. 623 4224.033 4194. 959 4232. 423 4278. 548 4245. 949 4251. 740 4251. 468 4246. 022 4264. 198 4231.803 4157. 957 4099.060 4005.858 3993. 240 3990. 642 3976. 262 3949. 027 3918. 408 3929. 605 3930. 271 3917. 397 3892. 391 3885.953 3890.599 46 V. S. COAST AND GEODETIC SUBVEY SPECIAL PUBLICATION NO. 22. Elevations of permanent bench marks — Continued. Place. Near Desert, Nev Upsal, Nev Do Near Falais, Nev Massle, Nev Do Hazen, Nev Do Patna, Nev Near Patna, Nev Argo, Nev Do Luva, Nev Fernley, Nev Do Gilpin, Nev Derby, Nev Near Derby, Nev Do Thisbe, Nev Do Clark.Nev Near Ditho, Nev Hafed, Nev Near Vista, Nev Do Do Vista, Nev Sparks, Nev Reno, Nev Do Lawton, Nev , Near Verdi, Nev Verdi, Nev , Murine >1 Nev Do Near Marcnol, Nev Calvada, Cal Mystic, Cal Iceland, Cal Near Prosser Creek, Cal Truckee,CaI Tunnel, Cal Near Eder, Cal Summit, Cal Near Spruce, Cal Cisco, Cal Emigrant Oap.Cal Blue Canyon, Cal Orel. Cal Towle,Cal , Gold Run, Cal Near Wirt, Cal Colfax, Cal Lander, Cal Near Clippergap, Cal. . . Do East Auburn, Cal ... Near New Castle, Cal Near Rocklin, Cal... Near Roseville, Cal. . Roseville, Cal Near Antelope, Cal. . Antelope, Cal Near Benali, Cal Elvas.Cal Brighton, Cal Near Florin, Cal Do Elk Grove, Cal McConrell, Cal Need, Cal Gait, Cal Jahant,Cal Designation of bench mark. Eg.... F 8 (S. P.) G s H 8 (S. P.) Is J. K 8 (S. P.) La Ma Ne(S. P.) Oa(S. P.) P« Q« R« Sa(U. S. G. S.). T, U 8 (S.P.) V,(S. P.) W 8 (S. P.) X 8 (S.P.) Y 8 (S.P.) Z.(8. P.) A,(S. P.) B, C(8. P.) D,(S. P.) E,(S. P.) F, G, H, U (U. S. G. S.). J« K, L,(S. P.) F 8 E D, Yio Xio W, V,o U I0 T 10 Sio... Rio Qio Pio On N» Mio Lio Kio. Jio I» H,o Gio Fio Eio Di» Cio Bio- Aio Z, (U.S. G.S.) . Yj X, W„ V, U,(U. 8. G. S.) T, (V. 8. G.S.) S»(U. S. G. S.). R» (U. S. G. S.) Q. P»(U. 8. G. 8.) 0» (U. S. G. S.) Standard elevation. Meters. 1189.696 1189. 186 1190. 412 1199. 499 1211. 720 1216. 708 1220.908 1220.222 1237.988 1242. 878 1241. 610 1241. 706 1258. 071 1265. 124 1265.834 1268.580 1268. 354 1267. 957 1269. 869 1286.231 1287. 423 1294. 236 1309. 489 1334. 058 1338. 144 1338.292 1339. 658 1339. 532 1347. 906 1370. 224 1389. 031 1415. 966 1459.919 1478. 104 1511. 948 1512,388 1514. 731 1533. 870 1573. 053 1648. 909 1709. 909 1773. 860 1928.122 2005. 54S 2122. 855 1984. 753 1805.200 1588. 645 1429.947 1346. 788 1135. 040 967. 038 732.022 736.123 699.753 669.220 535. 154 414.232 297. 432 76.756 82.652 48.814 44.638 47. 759 15.928 12.179 15.222 11.063 11.365 15. 194 14.313 13. 307 14.061 14.888 Feet. 3902. 866 3901. 521 3905. 543 3935. 356 3975. 451 3991. 816 4005. 596 4003. 345 4061. 632 4077.676 4073.515 4073. 830 4127. 521 4150. 661 4152.990 4162.000 4161. 258 4159. 956 4166.229 4219. 909 4223.820 4246. 173 4296. 215 4376. 822 4390. 227 4390. 713 4395. 195 4394. 781 4422. 255 4495. 477 4557. 179 4645. 549 4789. 751 4849. 413 4960. 449 4961. 893 4969. 580 6032. 372 6160. 925 6409. 796 5609. 926 6819. 739 6325. 847 6579. 869 6964. 733 6511.644 6922. 560 6212. 079 4691. 418 4418.587 3723. 877 3172. 684 2401. 642 2415. 097 2295.773 1867. 516 1755. 751 1359. 026 975.825 251.824 172.742 160. 151 146. 450 156.689 52.257 39. 957 49.941 36.296 37.287 49. 849 46. 959 43.658 46. 132 48. 845 Place. Near Acampo, Cal Do Lodi.Cal Near Lodi, Cal Pearson, Cal Near Hammer, Cal Do Near El Pinal, Cal Near Stockton, Cal Stockton, Cal Do Near Stockton, Cal Near French Camp, Cal. Do Do Near Lathrop, Cal Lathrop, Cal Do Near Lathrop, Cal Near I!an ta, Cal Ban ta, Cal Tracy, Cal Do'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'. Near Tracy, Cal Midway, Cal Near Midway, Cal Near Cayley, Cal Near Altamont, Cal Do . Altamont, Cal Near Altamont, Cal ... . Near Livermore, Cal . . . Do Livermore, Cal Near Livermore, Cal . . . Radum, Cal Pleasanton, Cal Verona, Cal Ilrightside, Cal Farwell,Cal Near Niles, Cal Niles.Cal Do Irvington, Cal Near Warmsprings, Cal. Warmsprings, Cal Near Warmsprings, Cal. Near Miipitas, Cal Near Wayne, Cal San Jose, Cal Do Santa Clara, Cal Lawrence, Cal Sunnyvale, Cal Mountain View, Cal MavfleId,Cal PaloAlto.Cal Near Palo Alto, Cal Menlo Park, Cal Redwood City. Cal San Carlos, Cal Belmont, Cal Beresford, Cal San Mateo, Cal Do Burlingame, Cal Millbrae,Cal San Bruno, Cal Holy Cross, Cal San Francisco, Cal Do Do Do Designation of bench mark. N, M, (U.S. G.S.).. L».. KjfU.S. G. S.). Js(U. 8. G. 8.)... h. H, (U.S. G.S.).. Gs t F 9 (U. S. G. S.).. E, D, C, B, (U. S. G. S.). A« Z». Y, X, W 8 (U. S. G. S.). V 8 T 8 (U. S. G. S.).. S 8 (U. S. G. 8.).. Ra Q. P 8 (U. 8. G. S.).. Oa(U. S. G. S.).. Na M 8 L 8 Ka Ja(U. S. G. S.)... Is Ha Ca F 8 (U. S. G. 8.).. Ea D„ Cs B 8 A 8 Z 7 (U. 8. G. 8.). Y; X, w, V, u, T, 8t R» Qt P 7 (U. 8. G. 8.). O, N: M, L, K, J. Ir H, F,. Kr. I);. (',.. B>. A; Z s Y c X„ W. Citv 418. City 386. City 640. City 635. Standard elevation. Meters. 15.468 16. 219 15. 838 13. 972 11.582 10. 184 8.738 8.558 6.269 7.081 5.994 5.312 4.278 5.402 6.952 5.900 6.870 6.194 8.295 6.246 6.851 16.606 18.342 18.028 31.383 107. 125 128.917 150. 397 180.025 219. 224 225.513 218.270 195. 282 163.717 148.655 140.422 112.049 102. 518 92.234 68.746 51.053 37. 912 26.426 25.686 21.345 9.796 12.821 4.797 5.223 20.630 29.900 27. 470 22.997 20.419 29.800 23.652 10.009 18.922 22.410 21.529 3.875 7.846 10. 610 6.987 8.3(9 7.875 9.308 5.618 8.142 26.885 94. 789 58.661 59. 391 4& 559 Feet. 50. 748 53.212 51.962 45. 840 37.999 33.412 28.668 28.077 20.568 23.232 19.665 17.428 14.035 17.723 22.808 19. 357 22.539 20. 321 27.215 20.492 22.477 54. 150 60.177 59.147 102.962 351. 459 422. 955 493. 427 590. 632 719. 237 739. 871 716. 107 Ma 888 537.128 487. 712 460. 701 367.614 336. 344 302. 604 225. 544 167. 496 124. 383 86.699 84. 271 70.029 32. 139 42.064 15.738 17. 136 67.684 98.097 90.124 75. 449 66.991 97. 769 77. 598 32. BS8 62.080 73.523 70.633 12.713 25.741 34. 810 22.923 27. 392 25. 837 3a 538 18.432 26.713 88.205 310. 987 192. 457 194. 852 159.314 PEECISE LEVELING, BEIGHAM TO SAN FBANCISCO. Elevations of top of rail in front of railroad stations. Place. Brigham.Utah.... Corinne, Utah Promontory, Utah. Kelton,Utah Peplin.Utah Ombey.Utah Romola, Utah Lucin,Utah Tecoma.Nev Ullin, Nev Wright, Nev Loray, Nev Omar, Nev Cobre,Nev Valley Pass, Nev.. Icarus, Nev Pequop, Nev Moor, Nev Cedar,Nev Kaw.Nev Wells, Nev Alazon,Nev Tulasco.Nev 8tarr, Nev Nardi.Nev Deeth, Nev.. Natchez, Nev Rasld.Nev Halleck.Nev Elburs, Nev Ryndon, Nev Osino,Nev ,ke Standard elevation. Meters. Feet. 1312. 83 1289. 51 1491.61 1287. £0 1349.91 1437. 28 1410. 32 1363.26 1465.25 1601.98 1647.75 1712.54 1779.95 1304. 05 1850. 39 1861.01 1872.41 1878. 50 1819.49 1777.38 1715.26 1703.91 1680.11 1675.92 1648. 91 1627.46 1613. 59 1603. 16 1593.04 1585.55 1571.64 1563.91 1553.27 1541.86 1530.54 1518.85 1511.19 1498.88 1493. 98 1486.11 1476.35 Place. Coin. Elko, Nev.. Avenel,Nev Moleen.Nev Tonka, Nev. Vivian, Nev Carlin.Nev. Tvrol,Nev. Palisade, Nev 1 468° 55 Gerald, Nov J«|;^ 1441.86 1430.53 1109.94 1397.05 1386.59 1374. 65 1373.77 1355.65 1343.43 1333. 05 1334.31 1337.42 Harney, Nev Cluro.Nev Beowawe, Nev Farrel,Nev Mosel,Nev Argenta.Nev ......... Battle Mountain, Nev Valmv.Nev Stonohouse, Nev Horrin,Nev Iron Point, Nev Comus.Nev Golconda, Nev \ Z.!f 46 Tale, Nev...... 132o'.27 Winnemucca, Nev Ji,. 2 g Costive, Nov iW 98 Hill City, Nev , \vsm Imlay, Nov ■ — .™ n go Humboldt, Nev i ™«' 23 Rye Patch, Nev [^ g4 Oreana, Nev JX.o' o, Woolsey, Nev \"*r ~ Granite Point, Nev | »™;J| Toulon, Nev. Toy.Nev Ocala, Nev Huxley, Nev Parrari.Nev Desert, Nev Upsal, Nev Falais.Nev Massle, Nev Hazen, Nev Argo.Nev Fernley, Nev Derby, Nev Thisbe,Nev Clark, Nev Dltho, Nev Hafed,Nev Vista, Nev Sparks, Nev Reno, Nev Mosul, Nev Cafvada,Cal Floriston, Cal Wickes,CaL Boca, Cal Winsted.Cal Truckee, Cal Tunnel, Cal Eder.Cal Lake View, Cal.... Summit, Cal Soda Springs, Cal.. Spruce, Cal 1197.59 1186.93 1190.32 1184.25 1186.98 1100. 89 1204. 92 1212. 17 1222.16 1243.23 1266.09 1268. 39 1275. 75 1296. 46 1311.74 1333. 73 1339. 58 1347. 80 1369. 70 1443.64 1536. 47 1620.65 1632.37 1685.73 1743.90 1772.76 1950.36 2011.74 2068.15 2121.73 2058. 93 1991.76 4307. 37 4230.67 4903. 57 4224.07 4423. 83 4715.48 4627. 02 4472.63 4807.24 5255. 83 5405.99 5618. 56 5839.72 5913. 79 6070. 82 6105. 66 6143.07 6163. 05 5969.44 5831.29 6627. 48 5590.24 5512.16 5498.41 5409.80 5339. 42 5293.92 5259. 70 5226. 50 6201.93 5156. 29 5130. 93 5096.02 5058.59 5021.45 4983. 09 4957.96 4917.58 4901. E0 4875. 68 4843. 66 4818.07 4775.02 4730.50 4693. 33 4625. 78 4583.49 4.549.17 4510. 00 4507.11 4447. 66 4407. 57 4389. 92 4377.65 4387. 85 4322. 37 4331. C9 4298. 84 4225. 65 4193.00 4234.31 4252. 71 4156.29 4096.55 3921.19 3930.27 3929. 09 3894. 12 3905.24 3885.33 3894.28 3907.11 3953. 14 3976. 93 4009. 70 4078.83 4153.83 4161.38 4185.52 4253. 47 4303.60 4375. 75 4394.94 4421.91 4493. 76 4736. 34 5040.90 5317. 08 5355. 53 5530. 60 5721.45 5816. 13 6398. 81 6600.18 6785.26 6961.04 6748.44 6534.63 47 Standard elevation. Meters. Feet. Troy, Cal Tamarack, Cal Cisco, Cal Crystal Lake, Cal Yuba Pass, Cal Smart, Cal Emigrant Gap, Cal Fulda, Cal Blue Canyon, Cal Orel, Cal Midas, Cal Gorge, Cal Towle, Cal Alta, Cal Dutch Flat, Cal Gold Run. Cal Magra, Cat Capom. Cal Wirt, Cal Colfax, Cal Lander, Cal New England Mills, Cal Applegate, Cal Clippergap, Cal Bowman, Cal Nestor, Cal Auburn, Cal Flint, Cal Zcta, Cal Newcastle, Cal Penryn, Cal Loomis, Cal Ftocklin, Cal Roseville, Cal Antelope, Cal Walerga, CaL Benali,Cal Brighton, Cal Polk.Cnl Davis, Cal Florin, Cal Graham, CaL Sibeck, Cal Elk Grove, Cal McConnell, Cal Arno, Cal Need, Cal Gait, Cal Forest Lake, CaL Acampo, Cal Lodi.Cal Mettler, Cal Armstrong, Cal Pearson, Cal Racimo, Cal Castle, Cal Jam, Cal El Pinal, Cal Stockton. Cal Hislop, Cal. French Camp, Cal Lathrop, Cal. Banta, Cal Tracy, Cal Ellis, Cal ;; 108 ; 61 Midway, Cal. ■ 225 os Altamont.Cal | lfw 74 147. 39 113.93 112.84 109.90 106.99 92.18 79.55 63.65 58.98 49.81 40.62 25.81 10.02 13.30 6.04 27.77 23.01 29.89 24.32 17.96 19.11 20.56 16.07 7.56 7.18 7.66 8.89 8.49 7.89 1940.73 1838.51 1806.99 1754.89 1711.02 1630.99 1588.29 1531.61 1428. 88 1343. 78 1262. 63 1190.00 1125.20 1097.87 1033. 32 982 47 883.62 809.61 744. 30 735.22 695. 70 694.23 614.13 535.52 492.89 426. 78 413.45 397.09 356.84 291. 14 189.68 120.36 74.75 48.51 49.04 32.59 15.40 15.29 13.07 12.66 12.36 12.32 12.91 15.26 14.33 11.77 12.82 14.41 15.12 17.21 15.71 13.93 12.87 12.22 11.62 10.40 8.98 7.52 5.93 6.81 6.26 6.76 8.29 17.81 22.12 XTlraar, Cal... I.ivermore, CaL Eliot, Cal Remillard, Cal Radum, Cal... Ploasanton, Cal Verona, Cal Sunol.Cal Brlghtside.Cal Mayborg, Cal Farwell.Cal Alston.Cal Niles, Cal Irvington, Cal....... Warmsprings.Cal... Milpitas, Cal San Jose, Cal.... Santa Clara, Cal Sunnyvale, Cal...-. . Mountain View, Cal. Castro, Cal Palo Alto, Cal.. Menlo Park, Cal Fair Oaks, Cal San Carlos, CaL Beresford, Cal. San Mateo, CaL. Burlingame, Cal Milbrae, Cal San Bruno, Col 6367.21 6195.89 5928.43 6757.50 5613.57 5351.01 5210.91 5024.96 4687.92 4408.72 4142.48 3904.19 3691.59 3601.93 3390.15 3223.32 2899.01 2656.20 2441.92 2412.13 2282.48 2277.65 2014.86 1756.95 1617.09 1400.19 1356. 46 1302. 79 1170.73 955. 18 622.31 394.88 245.24 159. 15 160. 89 106.92 60.52 50.16 12.88 41.64 40.55 40.42 42.36 50.07 47.01 38.62 42.06 47.28 49.61 56.46 51.54 45.70 42.22 40.09 38.12 34.12 29.46 24.67 19.46 22.34 20.54 22.18 27.20 68.43 72.57 356.33 738. 45 556.89 483. 56 373.79 370.21 360. 56 351.02 302.43 260.99 208.83 193.50 163. 42 133.27 84.68 32.87 43.64 19.82 91.11 75.49 98.06 79.79 58.92 62.70 67.45 52.72 24.80 23.58 25.13 29.17 11.45 26.79 48 U. S. COAST AND GEODETIC SURVEY SPECIAL PUBLICATION NO. 22. DESCRIPTIONS OF BENCH MARKS. 1 GENERAL NOTES DESCRIBING DIFFERENT FORMS AND MARKINGS OF BENCH MARKS. Note 1. — This type of bench mark is the red metal disk designed by the Coast and Geodetic Survey, lettered "U. S. Coast and Geodetic Survey, B. M. $250 fine or imprisonment for disturbing this mark." The disk is 3 inches in diameter, with a 3-inch tenon upon the back for setting it, and is set in cement flush with a horizontal or vertical surface. In the latter case a horizontal mark cut on it, or the horizontal mark of a cross, is the bench mark. Note 2. — This type of bench mark has the same lettering as that referred to in note 1, and is a 3-inch red metal cap, somewhat curved, screwed upon a 4-foot or 4J-foot iron pipe set in the ground and usually cemented at the base, from 4 to 6 inches being exposed above the ground. The base of the pipe is split and spread to a diameter of about a foot. For placing the foot of the level rod accurately a square or a small circle was cut in outline in the center of the cap. Note 11. — The bottom of hole about 25 millimeters square and about 4 to 5 millimeters deep, cut in the top of a stone or cement post about 4 feet long and with rectangular top from 4 to 8 inches on a side, projecting about 6 inches from the ground. The top of the post is lettered " U. S. B. M." Limestone posts are used between Holland and New Braunfels, Tex., and black lava posts between Pocatello and Owyhee, Idaho. Note 11a.— A red metal disk, like that described in note 1, set in the top of a stone or cement post about 4 feet long and with a rectangular top from 4 to 8 inches on a side, projecting about 6 inches from the ground. Note 17.— A 3-inch aluminum or bronze disk ' lettered "U. S. Geological Survey B. M. $250 fine or imprison- ment for disturbing this mark. Elevation above sea — feet. Datum — ." Each disk is stamped with the approximate elevation in feet and a letter or letters to indicate the datum plane. This elevation and the datum letter or letters usually form the name by which the bench mark is designated in this publication. Note 18. — This type of bench mark has the same lettering as that referred to in note 17, and is a 8-inch aluminum or bronze cap riveted upon a 3-inch iron pipe, set in the ground, 5 to 6 inches being exposed above the ground. A cross cut in the center of the top is the bench mark. DESCRIPTIONS OF PERMANENT BENCH MARKS BETWEEN BRIGHAM, UTAH, AND BEOWAWE, NEV., 191 1. R. — At Brigham, Boxelder County, Utah, 15 meters south of the second road crossing north of the station, in a field west of the tracks, inside and 0.6 meter from the fence, about halfway between mile poles 21 and 22 and about 1.5 meters above the level of the tracks. Note 11.* J,.— At Brigham, Boxelder County, Utah, about 100 meters south of the Oregon Short Line Railroad station, in the top surface of the northwest stone pillar of the railroad water tank. Note 1.* Kj.— At Brigham, Boxelder County, Utah, in the eastern vertical face of the south side of the stone steps leading to the west entrance of the Boxelder County Courthouse, about 1.5 meters above the ground. Note 1.* L,.— At Eoneyville, Boxelder County, Utah, in the west face of the concrete foundation of the Oregon Short Line Railroad station, directly beneath the telegraph operator's window and just behind the semaphore tower, about 0.2 meter above the platform. Note 1.* T.— At Dewey, Boxelder County, Utah, 180 meters south of the depot, on the right of way of the Oregon Short Line Railroad, 15 meters east of the main tracks. Note 11.* Mj— Near Corinne, Boxelder County, Utah, about 4 telegraph poles west of mile pole 3 on the right of way of the Brigham-Corinne cut-off, 14 meters south of the tracks, 1.2 meters north of the south line fence, about 1.5 meters below the track. Note 11.* N 9 . — At Corinne, Boxelder County, Utah, directly south of the middle of the freight station, 42.4 meters west of the west end of the old passenger station, 18.7 meters south of the Southern Pacific Railway main track, one-half meter north of the south line fence, and about 0.6 meter below the track. Note 11.* 9 .— Near Corinne, Boxelder County, Utah, between the tenth telegraph pole east of Southern Pacific mile pole 806 and the south line fence 1 meter north of the latter, 150 meters east of the small bridge that crosses the irrigation ditch at the point where the right of way narrows, 14.3 meters south of the tracks. Note 2.* p 9 —Between Corinne and Balfour, Boxelder County, Utah, about 1J telegraph poles east of mile pole 804, 50 meters east of the whistle post, at the road crossing, on the Southern Pacific right of way one-half meter north of the south line fence and 14.8 meters south of the track. Note 2.* Q 9 .— At Balfour, Boxelder County, Utah, about 7 telegraph poles west of mile pole 801, 98 meters east of the west- ernmost of the two switch stands at the west end of the siding, on the right of way of the Southern Pacific Railway, one-half meter north of the south line fence, 14.8 meters south of the main track and about 1 meter above it. Note 2.* R,.— Near Hansen, Boxelder County, Utah, about 2 telegraph poles east of mile pole 798 on the right of way of the Southern Pacific Railway, 0.9 meter south of the north line fence, 14.3 meters north of the track, and about 1.2 meters above it. Note 11.* S,.— At Hansen, Boxelder County, Utah, about midway between the ends of the siding, one-half telegraph pole west of the pole that carries the station sign (795.7 miles), in the line of the telegraph poles, 13 meters south of the Southern Pacific main track. Note 11.* i Any person who finds that one of the bench marks here described is disturbed, or that the description is not in accordance with thefacts.ls requested to notify the Superintendent of the United States Coast and Geodetic Survey, Washington, D. C. * See above. PRECISE LEVELING, BRIGHAM TO SAN FRANCISCO. 49 T 9 . — Near Hansen, Boxelder County, Utah, about 2 telegraph polea west of mile pole 793 on the right of way of the Southern Pacific Railway, 8.9 meters north of the south line fence, and 5.8 meters south of the railway track. Note 2.* U 9 . — At Blue Creek, Boxelder County, Utah, situated on the right of way of the Southern Pacific Railway, opposite the water tank, 14.8 meters west of the west end of the pumping station, 10 meters north of the south line fence, 12.2 meters south of the southernmost siding, 24.5 meters south of the main track. Note 11.* V,.— Near Blue Creek, and Kolmar, Boxelder County, Utah, about 4 telegraph poles east of mile pole 790, on the Southern Pacific Railway right of way, 0.8 meter north of the south line fence, 14.4 meters south of the railway track. Note 2* W 9 . — At Kolmar, Boxelder County, Utah, about 0.2 telegraph pole south of the pole that carries the station Bign (789.1 miles), on the right of way of the Southern Pacific Railway, 6.7 meters east of the west line fence, 32.2 meters west of the main track of the Southern Pacific Railway. Note 11.* X 9 . — At Surbon, Boxelder County, Utah, about 2 telegraph poles north of the pole that carries the station sign (786.1 miles), 6.2 meters west of the east line fence, on the right of way of the Southern Pacific Railway, 4 meters east of the main track. Note 11.* Y 9 . — At Promontory, Boxelder County, Utah, on the Southern Pacific right of way, on a line joining the west end of the railway station with the east edge of the door to the United States post office, 45.1 meters north of the main track, 4.2 meters south of the north line fence, 48.7 meters from the northwest corner of the station house. Note 11.* Z 9 . — Near Promontory, Boxelder County, Utah, at mile pole 778 on the right of way of the Southern Pacific Rail- way, 0.7 meter north of the south line fence, 15 meters south of the track, and about 1.2 meters below it. Note 2.* A 10 . — Near Promontory, Boxelder County, Utah, between Promontory and Rozel, on the right of way of the Southern Pacific Railway, 3 telegraph poles east of mile pole 775, 8.1 meters north of the south line fence, and about 1.8 meters above the track. Note 2.* B 10 . — At Rozel, Boxelder County, Utah, on the Southern Pacific Railway, right of way, 46 meters east of the east end of the water tank, 14.6 meters Bouth of the main track, 0.8 meter north of the south line fence. Note 11.* C, . — Near Rozel, Boxelder County, Utah, one-half meter south of mile pole 770, on the right of way of the Southern Pacific Railway, 15.4 meters south of the main track. Note 2.* D 10 . — Near Lake, Boxelder County, Utah, 1.42 meters north of mile pole 766, on the right of way of the Southern Pacific Railway, 10.8 meters south of the track, and about 1.5 meters below it. Note 2.* E, . — At Lake, Boxelder County, Utah, 1.8 meters north of mile pole 763, on the right of way of the Southern Pacific Railway, 15.4 meters south of the main track, and about 0.6 meter below it. Note 11.* F 10 . — Near Lake, Boxelder County, Utah, 1.5 meters north of the fourth telegraph pole east of mile pole 759, on the right of way of the Southern Pacific Railway, 13.2 meters south of the track. Note 2.* G 10 . — At Monument, Boxelder County, Utah, at the west end of the siding on the right of way of the Southern Pacific Railway, 0.8 meter south of the seventh telegraph pole west of the pole that carries the station sign, 10.8 meters north of the track. Note 11.* H 10 . — Near Monument, Boxelder County, Utah, on the Southern Pacific Railway right of way, 1.1 meters south of mile pole 752, 19.5 meters south of the track, and about 1.5 meters below it. Note 2.* I I0 . — Near Monument, Boxelder County, Utah, 1.2 meters north of mile pole 748, on the right of way of the Southern Pacific Railway, 14.3 meters south of the track, and about 1 meter below it. Note 11.* J 10 . — Near Kelton, Boxelder County, Utah, 1 meter north of the seventh telegraph pole west of mile pole 744 on the Southern Pacific Railway right of way, 14.5 meters south of the track, and about 1 meter above it. Note 2.* K 10 . — At Kelton, Boxelder County, Utah, 36 meters east of the east end of the Southern Pacific freight station, 29.6 meters north of the main track. Note 1.* L 10 . — Near Kelton, Boxelder County, Utah, 1 meter east of a telegraph pole on the right of way of the Southern Pacific Railway and directly across the track from mile pole 736, 22.8 meters west of the track. Note 11.* M 10 . — Near Peplin, Boxelder County, Utah, in the vertical side of the deep cut 2 telegraph poles east of mile pole 733, 25 meters west of the east end of the cut, 1.5 meters above the track, and 2 meters south of it. Note 1.* N 10 . — At Ombey, Boxelder County, Utah, 1 meter northwest of mile pole 730, 14.8 meters southeast of the Southern Pacific Railway main track, 30 meters northeast of the switch stand at the northeast end of the wye, 48.4 meters north- east of the semaphore. Note 2.* Oio- — Near Romola, Boxelder County, Utah, about one-half mile west of the station sign, 6 telegraph poles east of mile pole 724, 16.1 meters south of the Southern Pacific Railway track, 1 meter north of a telegraph post, 40 meters east of a whistle post. Note 2.* P 10 . — Near Romola, Boxelder County, Utah, on the right of way of the Southern Pacific Railway, south of the track, about 1 meter north of mile pole 719. Note 2.* Q 10 . — Near Terrace, Boxelder County, Utah, 1.3 meters north of mile pole 712 on the right of way of the Southern Pacific Railway, 13.7 meters south of the track, and about 1.2 meters above it. Note 2.* R 10 . — At Terrace, Boxelder County, Utah, in the northeast corner of the brick structure of the machine shop, about 1.5 meters above the ground. Note 1.* 8 10 — Near Terrace, Boxelder County, Utah, 1 meter north of mile pole 705 on the Southern Pacific Railway right of way, 14.7 meters south of the track. Note 2.* * See p. 48. 53167°— 14 4 50 U. S. COAST AND GEODETIC SURVEY SPECIAL PUBLICATION NO. 22. T 10 . — At Bovine, Boxelder County, Utah, on the Southern Pacific Railway right of way about 1.4 telegraph poles east of mile pole 699 and on the opposite side of the track, 36.8 meters west along the track of the section car house, 14.1 meters north of the main track. Note 2.* U 10 . — Near Bovine, Boxelder County, Utah, on the right of way of the Southern Pacific Railway, 1.2 meters north of mile pole 695, 14.6 meters south of the track. Note 2.* V 10 .— Near Umbria Junction, Boxelder County, Utah, 0.9 meter north of mile pole 690, 14.5 meters south of the Southern Pacific Railway track. Note 2.* W 10 . — At Lucin, Boxelder County, Utah, in the top of the southern one of the two westernmost stone pillars under the water tank. Note 1.* X 10 . — About one-half mile east of Umbria Junction, Boxelder County, Utah, between the old Terrace line of the Southern Pacific Railway and the Lucin Cut-off, 1.4 meters east of the old-line telegraph pole that stands about 75 meters northeast of the whistle post at the crossing on the main line, 53.2 meters north of the eastbound main track, about 45 meters north of the westbound main track and 20.6 meters south of the old Terrace line. Note 11.* Y, . — Near Umbria Junction, Boxelder County, Utah, 0.6 meter north of the sixth telegraph pole east of mile pole 679, about one-fourth mile west of the junction; at the west end of the cut that runs west from the junction point; 15.7 meters north of the eastbound track of the Southern Pacific Railway and about 0.6 meter above it. Note 11.* Z I0 . — Near Umbria Junction, Boxelder County, Utah, 0.9 meter north of mile pole 677, 14.3 meters north of the east- bound track of the Southern Pacific Railway. Note 2.* A u . — At Garlney, Boxelder County, Utah, directly opposite the station sign, 59.7 meters south of the eastbound track of the Southern Pacific Railway, 0.9 meter north of the south line fence. Note 11.* I 3 . — Near Tecoma, Elko County, Nev., in the north side of the granite post which marks the boundary between the States of Utah and Nevada, 19.2 meters south of the Southern Pacific Railway eastbound track. Note 1.* J,. — At Tecoma, Elko County, Nev., about two-fifths of a mile east of the Southern Pacific Railway station; 6 tele- graph poles east of mile pole 670, opposite the east post of a rail-rack; 15.3 meters south of the eastbound track, 0.8 meter north of a telegraph pole. Note 11.* K 3 . — Near Tecoma, Elko County, Nev., 73.2 meters south of mile pole 668, 59.8 meters south of the eastbound main track of the Southern Pacific Railway, 1.3 meters north of the south line fence. Note 11.* L 3 . — Near Tecoma, Elko County, Nev., situated 47 meters north from mile pole 666, 56.3 meters north from the westbound track of the Southern Pacific Railway, 0.9 meter south of the north line fence. Note 2.* M 3 . — At Akbar, Elko County, Nev., about 9 telegraph poles east of mile pole 665 with two semaphore towers in range, 60.2 meters south of the Southern Pacific Railway main track, 1 meter north of the south line fence. Note 11.* N 3 . — About one mile east of Montello, Elko County, Nev., 47 meters north of mile pole 664, 56.5 meters north of eastbound line of the Southern Pacific Railway, 100 meters east of cattle guard, 1 meter south of the north line fence. Note 2* 3 . — At Montello, Elko County, Nev., in the top surface of the western one of the two northernmost stone pillars under the water tank. Note 1.* P 3 . — At Montello, Elko County, Nev., in the southeast corner of the grass plat in front of the Southern Pacific Hotel, about 1 meter from the corner. Note 11.* Q 3 . — At Banvard, Elko County, Nev., in line with the west side of the section house, 60 meters north of the east- bound track of the Southern Pacific Railway, 1.3 meters south of the north line fence. Note 11.* R 3 . — At Noble, Elko County, Nev., directly opposite the station sign on the northwest side of the Southern Pacific Railway track at the rear of the signal tender' s dwelling; about 1 meter southeast of the northwest line fence. Note 11*. S 3 . — At Ullin, Elko County, Nev., directly opposite the station sign in a fence corner 59.2 meters northwest of the eastbound line of the Southern Pacific Railway, 7 telegraph poles northeast of mile pole 656. Note 11.* T 3 . — At Wright, Elko County, Nev., 43 meters northwest of mile pole 654, 57.7 meters northwest of the Southern Pacific Railway track, 1.2 meters southeast of the northwest line fence. Note 11.* U 3 . — At Loray, Elko County, Nev., opposite the yellow dwelling house of the section foreman, 1 telegraph pole west of section car house 46, 6 telegraph poles east of mile pole 652, 60.3 meters north of the Southern Pacific Railway main track, 0.9 meter south of the north line fence. Note 11.* V 3 . — At Omar, Elko County, Nev., 0.6 meter north of the eleventh telegraph pole east of mile pole 647, 5.6 meters north of the station sign, 15.0 meters north of the main track of the Southern Pacific Railway. Note 11.* W 3 . — At Cobre, Elko County, Nev., 0.9 meter northeast of the fourth telegraph pole northwest of the railway station, 14.2 meters northeast of the main track of the Southern Pacific Railway, about 100 meters northwest of the freight station. Note 11.* X 3 . — At Cobre, Elko County, Nev., 0.9 meter northeast of mile pole 645, 14.4 meters northeast of the Southern ' Pacific Railway and about 1 meter below the track. Note 2.* Y 3 . — Near Cobre, Elko County, Nev., 7 telegraph poles east of mile pole 643, the top of an iron spike in the top of the north headwall of culvert No. 643A. Z 3 . — At Valley Pass, Elko County, Nev., situated 1 meter south of the firet telegraph pole east of the Southern Pacific Railway station, about 15 meters south of the track and within the turning wye. Note 11.* A v — Near Valley Pass, Elko County, Nev., about 3.7 telegraph poles east of the mile pole 640, 75 meters west of the crossing, 29.3 meters north of the Southern Pacific Railway track, 1.4 meters south of the north line fence. Note 2.* ♦See p. 48. PRECISE LEVELING, BRIG-HAM TO SAN FRANCISCO. 51 B 4 . — At Icarus, Elko County, Nev., 44 meters north of mile pole 638, 60 meters north of the main line of the Southern Pacific Railway, 1.2 meters ^outh of the north line fence. Note 11.* C 4 . — Near Icarus, Elko County, Nev., 50 meters west of the mile pole 635, on the east slope of a hill at the east end of a deep cut, 28.9 meters north of the Southern Pacific Railway track, and about on the level with the track near the set-off stand, 0.9 meter south of the north line fence. Note 2.* D 4 . — At Pequop, Elko County, Nev., in front of the section hands' quarters, 1 meter north of mile pole 633, 10 meters west of section car house No. 44. Note 11.* E 4 . — At Fenelon, Elko County, Nev., about 30 meters east of the Southern Pacific Railway station (628.4), 59.5 meters north of the main track. Note 11.* F 4 . — Near Holborn, Elko County, Nev., 2 telegraph poles east of mile pole 627, 28 meters north of the Southern Pacific Railway track, 0.9 meter south of the north line fence. Note 2.* G 4 . — At Holborn, Elko County, Nev., 40 meters east of section car house No. 43, 17.1 meters north of the main track of the Southern Pacific Railway, 0.8 meter north of a white telegraph pole which is 2 telegraph poles east of the station sign. Note 11.* H 4 . — At Anthony, Elko County, Nev., directly opposite the station sign, 6 telegraph poles west of the water tank, 29.9 meters south of the Southern Pacific Railway main track, 1.2 meters north of the south line fence. Note 11.* I 4 . — At Moor, Elko County, Nev., about 10 meters west of the Southern Pacific Railway station, 1 meter north of a white telegraph pole, 15 meters north of the main track, and about 1.5 meters below it. Note 11.* J 4 . — At Cedar, Elko County, Nev., 35 meters east of the station sign, about 2 telegraph poles east and 0.7 meter north of mile pole 614, 16.8 meters north of the Southern Pacific Railway track. Note 11.* K 4 . — At Kaw, Elko County, Nev., 1 meter north of mile pole 612, 10.5 meters north of the Southern Pacific Railway main track. Note 11.* L 4 . — Two miles east of Wells, Elko County, Nev., 0.9 meter north of mile pole 610, 10 meters north of the Southern Pacific Railway track. Note 11.* M 4 . — At Wells, Elko County, Nev., 1 meter north of the telegraph pole opposite the east end of the Southern Pacific Railway station, 12 meters north of main track. Note 11.* N 4 . — At Wells, Elko County, Nev., in the western one of the two northernmost concrete pillars under the South- ern Pacific Railway water tank. Note 1.* 4 . — Near Wells, Elko County, Nev., on the east slope of a hill at the east end of a deep cut, 3 telegraph poles west of mile pole 607, 65.5 meters north of the Southern Pacific Railway track, 1.3 meters south of the north line fence. Note 2.* P 4 . — Near Wells, Elko County, Nev., at mile pole 606, 1 meter south of the north line fence, 27.7 meters north of the Southern Pacific Railway track, and about 1.5 meters below it. Note 2.* Q 4 . — At Alazon, Elko County, Nev., 4.4 telegraph poles east of Southern Pacific Railway mile pole 604, one-quarter mile west of the station sign, 28 meters north of the track, 32.4 meters north of Western Pacific Railway track; and 0.9 meter south of the north line fence. Note 11.* R 4 . — Near Tulasco, Elko County, Nev., on the Southern Pacific Railway and near Starr, on the Western Pacific Railway at Southern Pacific mile pole 600, 4J telegraph poles west of Western Pacific mile pole 709, 29.1 meters south of the Western Pacific track, 33.5 meters south of the Southern Pacific Railway track, 1.3 meters north of the south line fence. Note 11.* S 4 . — Near Nardi, Elko County, Nev., one-half mile west of the west end of the siding, 12 telegraph poles west of Southern Pacific mile pole 595, 18 telegraph poles west of Western Pacific mile pole 704, 75 meters west of signal tower 5948, and 27.9 meters north of the Southern Pacific track, 32.3 meters north of the Western Pacific track, and 0.9 meter south of north line fence. Note 11.* T 4 . — About 1 mile east of Deeth, Elko County, Nev., about 200 meters west of the point where the Southern Pacific Railway begins to separate from the Western Pacific Railway, 3 telegraph poles west of Southern Pacific mile pole 592, 7 telegraph poles west of Western Pacific mile pole 701, 4.3 meters south of Southern Pacific track, 5.6 meters north of the Western Pacific track. Note 2.* U 4 . — At Deeth, Elko County, Nev., about one-half mile west of the Southern Pacific Railway station, 35 meters east of the west end of the siding, 0.7 meter south of the first telegraph pole east of signal tower 590.5, 15.5 meters south of the main track. Note 2.* V 4 . — At Natchez, Elko County, Nev., 4 telegraph poles east of mile pole 587 in range with signal towers 5871 and 5872, 17.4 meters south of the Southern Pacific Railway track; 1.7 meters south of the south line fence, outside the right of way. Note 2.* W 4 . — At Ilalleck, Elko County, Nev., 106 meters north of the Southern Pacific main track, 1.6 meters south of the north line fence, in range with the east gable of the railway station and about 1.5 meters above the track. Note 11.* X 4 . — At Elburz, Elko County, Nev., 2.8 meters north of mile pole 575, 18.9 meters north of the Southern Pacific Railway track, 20 meters west of section car house No. 38. Note 11.* Y 4 . — Near Elburz, Elko County, Nev., in the face of the rock at the east end of tunnel No. 5, north of the Southern Pacific Railway track, and about 0.6 meter above it. Note 1.* Z 4 . — At Ryndon, Elko County, Nev., 100 meters east of the station, 12 meters south of the Southern Pacific Railway track, 10 meters north of the Western Pacific Railway track, 1 meter west of a telegraph pole. Note 11.* * See p. 48. 52 U. S. COAST AND GEODETIC SUEVEY SPECIAL PUBLICATION NO. 22. A 6 . — Near Ryndon, Elko County, Nev., in the top surface of the west abutment of Southern Pacific Railway bridge No. 25 over Humboldt River, 300 meters east of tunnel No. 3, south of the track. Note 1.* B 5 . — At Osino, Elko County, Nev., 50.7 meters east of section car house No. 36, 0.9 meter east of a telegraph pole, 30.3 meters north of the Southern Pacific main track. Note 11.* C 6 . — At Coin, Elko County, Nev., 6.8 meters north of Southern Pacific Railway mile pole 562, 21 meters north of the Southern Pacific main track, about one-quarter mile northeast of Western Pacific mile pole 670. Note 11.* D 6 . — About 2 miles east of Elko, Elko County, Nev., 11.8 meters north of mile pole 560, 23.5 meters north of Southern Pacific Railway track, 1.5 meters south of the fence. Note 2.* E 5 . — About three-fourths of a mile east of Elko, Elko County, Nev., 8 telegraph poles east of mile pole 558, 58.8 meters north of the Southern Pacific Railway track, 1.1 meters south of the north line fence, and about 100 meters east of the cattle guard. Note 11.* F 5 (U. S. G. S.). — At Elko, Elko County, Nev., in the top surface, at the west end of the lower step leading to the south entrance of the Elko County courthouse; a cross marks the exact point. Note 17.* G 6 . — At Elko, Elko County, Nev., 50 meters east of signal tower 567.3 at the west end of the Southern Pacific siding, about one-half mile west of the railway station, 12.7 meters north of the track, and 1.3 meters north of a telegraph pole. Note 11.* H s . — About 3 miles west of Elko, Elko County, Nev., 1.2 meters north of Southern Pacific Railway mile pole 555, 15.5 meters north of the track. Note 2.* I s . — Near Avenel, Elko County, Nev., 1.2 meters north of mile pole 553, and 15.6 meters north of the Southern Pacific Railway track. Note 2.* J 6 .— At Avenel, Elko County, Nev., 75 meters east of the station sign, 30 meters west of the crossing, 58.7 meters south of the Southern Pacific Railway main track, and 2.6 meters north of the fence. Note 11.* K 6 . — Near Avenel, Elko County, Nev., 49 meters north of mile pole 550, 64 meters north of Southern Pacific Railway tracks, and 1.9 meters south of the north line fence. Note 2.* L 6 . — Near Moleen, Elko County, Nev., 34 meters north of mile pole 548, 48.3 meters north of the Southern Pacific Railway track, 1.3 meters south of the north line fence. Note 2* M 6 .— At Moleen, Elko County, Nev., 3 telegraph poles west of mile pole 546, opposite the station sign, 1 meter north of the south line fence, 61.3 meters south of the Southern Pacific Railway main track. Note 11.* N 6 . — Near Moleen, Elko County, Nev., in the top surface of the west abutment of Southern Pacific Railway bridge No. 24 over Humboldt River, north of the track. Note 1* 6 . — Near Tonka, Elko County, Nev., at mileage distance 542.6, in the top surface of the west abutment of bridge No 21 over Humboldt River, south of the track. It is the top of an iron pin. P 6 . — At Tonka, Elko County, Nev., 3.1 meters north of mile pole 542, 22.4 meters north of the Southern Pacific Railway main track, 39.2 meters south of the north line fence. Note 11* Q 6 — Near Tonka, Elko County, Nev., in the top surface of the west abutment of Southern Pacific Railway bridge No. 20 over Humboldt River, south of the track. It is the top of an iron bolt. R 6 .. — Near Vivian, Elko County, Nev., in the top surface of the east abutment of bridge No. 19 over Humboldt River, south of the track. It is the top of an iron bolt. S 6 .— At Vivian, Elko County, Nev., 65.9 meters south of the station sign, on the right of way of the Southern Pacific Railway, 59.6 meters south of the main track, 1.4 meters north of the line fence between the Southern Pacific Rail- way and the Western Pacific Railway, 16.3 meters north of the Western Pacific track, 9.3 telegraph poles east of Western Pacific mile pole 647, 2.8 telegraph poles west of Southern Pacific mile pole 539. Note 11* T 6 .— At Carlin, Elko County, Nev., in the grass plot halfway between the Southern Pacific Hotel and the Southern Pacific Railway station, 1 meter south of the front fence. Note 11* Uj.— About 2 miles west of Carlin, Elko County, Nev., 100 meters west of crossing 534A, 41 meters north of mile pole 534, 56 meters north of the Southern Pacific Railway track, 1.7 meters south of the north line fence. Note 11* V 6 .— At Tyrol, Eureka County, Nev., approximately at mile pole 532.6, 7.5 meters east of the station sign, 13.7 meters east of the Southern Pacific Railway main track, 1.4 meters west of the east line fence. W 6 . — At Palisade, Eureka County, Nev., 75 meters west of the west end of Southern Pacific Railway bridge No. 16 over Humboldt River, 30 meters east of tunnel No. 1, 13.7 meters north of the track, 14.5 meters south of the north line fence, 1 meter east of a telegraph pole. Note 11.* X s .— At Gerald, Eureka County, Nev., near the fence corner at the west end of the siding, 8 telegraph poles west of the station sign, 29.2 meters south of the Southern Pacific Railway track, 1 meter from the south line fence. Note 11.* Y 5 .— At Harney, Eureka County, Nev., 2.4 telegraph poles east of mile pole 518, 6.6 poles west of the station sign, 30 meters north of the Southern Pacific Railway track, 0.6 meter south of the fence. Note 11.* Z 6 .— At Cluro, Eureka County, Nev., 3.3 telegraph poles east of the station sign and of Southern Pacific Railway mile pole 514, 5.3 meters south of the second telegraph pole west of the Western Pacific Railway mile pole 623, 26.8 meters north of the Southern Pacific track, 34.5 meters south of the north line fence, and 19.1 meters south of the Western Pacific track. Note 11.* A,.— At Beowawe, Eureka County, Nev., in the top surface of the concrete base of signal tower 510.1 at the east end of the siding. Note 1.* ♦Seep. 48. PRECISE LEVELING, BEIGHAM TO SAN FRANCISCO. 53 B 8 . — At Beowawe, Eureka County, Nev., in the top surface of the concrete foundation (center pier) of the Western Pacific Railway water tank. Note 1* C 8 . — At Beowawe, Eureka County, Nev., 25 meters west of the west end of the Southern Pacific Railway station, 26 meters south of the Western Pacific Railway track, 19.8 meters north of the Southern Pacific track. Note 11.* DESCRIPTIONS OF PERMANENT BENCH MARKS BETWEEN BEOWAWE, AND MARMOL, NEV., 1912. G 6 . — At Ladoga, Eureka County, Nev., 0.3 mile east of the station sign, 75 meters east of mile pole 504, and 19 meters south of the Southern Pacific Railway track. Note 11.* H 6 .- — At Farrel, Eureka County, Nev., 120 meters east of the station sign, 10 meters east of section tool house No. 29, and 24 meters north of the Southern Pacific Railway track. Note 11.* I 6 . — At Mosel, Lander County, Nev., 100 meters east of the station sign, 90 meters west of mile pole 493, 0.8 meter north of the south line fence, and 60 meters south of the Southern Pacific Railway track. Note 11* J 6 . — At Argenta, Lander County, Nev., 100 meters east of the west point of the Southern Pacific Railway siding, 1.5 meters north of the south line fence and opposite a white-painted frame ranch dwelling house. Note 11* K 6 . — At Rosny, Lander County, Nev., 30 meters east of the station sign, 1.5 meters south of Southern Pacific Rail- way mile pole 482. Note 11 .* L 6 .' — At Battle Mountain, Lander County, Nev., on the southwestern one of the four central concrete pillars under the Southern Pacific Railway water tank, 50 meters west of the station. Note 1* M 6 .' — About 1.5 miles northwest of Battle Mountain, Lander County, Nev., at Southern Pacific Railway mile pole 474, 51.5 meters north of the track, 9.1 meters south of the north line fence. Note 11.* N 6 . — At Piute, Humboldt County, Nev., at the station sign, at Southern Pacific Railway mileage 470.8, 36.6 meters south of the track, 25.2 meters north of the south line fence. Note 11A.* 6 . — At Mote, Humboldt County, Nev., at the station sign, at Southern Pacific Railway mileage 466.3, 56.2 meters north of the track, 4.9 meters south of the north line fence. Note 11A.* P 6 . — At Valmy, Humboldt County, Nev., on top of the concrete subbase of the southeastern one of the four central pillars under the Southern Pacific Railway water tank. Note 1* Q 6 .- — 1.3 miles west of Valmy, Humboldt County, Nev., 9 meters north of mile pole 460, 28 meters north of the South- ern Pacific Railway track, 33 meters south of the north line fence. Note 11A* R 6 . — 0.3 mile west of Stonehouse, Humboldt County, Nev., on top of the south headwall of concrete culvert No. 456C over Humboldt River, 3.2 meters south of the Southern Pacific Railway track, and about 1.5 meters below it. Note 1* S,.— At Herrin, Humboldt County, Nev., 60 meters west of the east end of the siding, 28 meters west of a yellow building, 1.4 meters north of a red building, 27.4 meters south of the Southern Pacific Railway track. Note 11A* T 9 .- — At Iron Point, Humboldt County, Nev., 100 meters east of mile pole 448, 18 meters west and 36 meters north of the Southern Pacific Railway station, 60 meters north of the track, 0.7 meter south of the north line fence. Note 11A.* U„. — At Comus, Humboldt County, Nev., 11.2 meters west of the section tool house, 17.6 meters north of the South- ern Pacific Railway track, 0.5 meter south of the north line fence. Note 11A.* V 6 . — Near Preble, Humboldt County, Nev., on the top surface of the east abutment of Southern Pacific Railway bridge No. 441 C, which is bridge No. 3 over Humboldt River, 2 meters north of the track. Note 1* W„ (S. P.). — Near Golconda, Humboldt County, Nev., in the top surface of the west abutment of Southern Pacific Railway bridge No. 2 over Humboldt River, north of the track. The bench mark is the top of a round-headed iron bolt. The stone is marked on top with the railroad's value of the elevation, 4348.238 feet. X 6 . — At Golconda, Humboldt County, Nev., on the northwestern one of the concrete pillars under the Southern Pacific Railway water tank, 100 meters west of the station, 50 meters south of the track. Note 1.* Y 6 .— At Eglon, Humboldt County, Nev., 41.7 meters north of the Southern Pacific Railway track, 29.2 meters north of mile pole 429, 1 meter south of the north line fence. Note 11A.* Z 6 . — At Tule, Humboldt County, Nev., 250 meters west of mile pole 423, 100 meters east of the west point of the siding, 29 meters south of the Southern Pacific Railway track, 27 meters north of the south line fence, opposite the derailing switch to the spur, and in line with the telegraph poles. Note 11A.* A r . — At Winnemucca, Humboldt County, Nev., in the foundation of the Humboldt County courthouse, to the left of the entrance on Bridge Street. Note 1.* B 7 .— At Benin, Humboldt County, Nev., opposite the station sign, at Southern Pacific Railway mileage 412.2, 60.4 meters south of the track, 1.1 meters north of the south fence. Note 11A.* C 7 .— At Rose Creek, Humboldt County, Nev., 36.4 meters south of the south side in line with the west side of the station, 45 meters south of the Southern Pacific Railway track, 0.9 meter north of the fence. Note 11A.* D 7 — At Lamar, Humboldt County, Nev., 0.2 mile east of the station sign, 40 meters north of mile pole 402, 59.2 meters north of the Southern Pacific Railway track, 1 .3 meters north of the fence. Note 11A.* E 7 .— At Cosgrave, Humboldt County, Nev., south of the Southern Pacific Railway water tank, 30 meters south of the track, 0.7 meter north of the south line fence. Note 11A.* BUCtoft Library F 7 — At Dodon, Humboldt County, Nev., 4 telegraph poles west of mile pole 393, opposite the station sign, 59.8 meters south of the Southern Pacific Railway track, 1.6 meters north of the south fence. Note 11A.* * See p. 48. 54 U. S. COAST AND GEODETIC SUBVEY SPECIAL PUBLICATION NO. 22. G 7 . — At Mill City, Humboldt County, Nev., 175 meters west of the Southern Pacific Railway station, in the second line of telegraph poles, 0.6 meter east of the east fence around a yellow frame building, 37.6 meters south of the track. Note 11A.* H 7 . — At Imlay, Humboldt County, Nev., on the top of the northeastern concrete pillar under the Southern Pacific Railway water tank. Note 1.* I 7 . — At Humboldt, Humboldt County, Nev., on the south side of the concrete foundation under the yellow-painted building of the Southern Pacific Railway, opposite the water tank, about 75 meters west of the station, 25 meters north of the track. Note 1.* J 7 . — At Valery, Humboldt County, Nev., 300 meters east of the station sign, 200 meters west of mile pole 373, 60 meters north of the track, 1.0 meter south of the north line fence, 4.0 meters east of a gate in the fence. Note 11A.* K 7 (S. P.). — 3 miles west of Valery, Humboldt County, Nev., at railroad mileage 369.9, in the top surface of the south headwall of the culvert under the eastbound line of the Southern Pacific Railway . It is the top of a round-headed iron bolt and constitutes a bench mark of the Southern Pacific Railway. L 7 (S. P.). — 1.7 miles east of Rye Patch, Humboldt County, Nev., at railroad mileage 367.7, south of the track, on the top surface of the east concrete abutment of the small bridge under the eastbound line of the Southern Pacific Railway. It is the top of a round-headed iron bolt and constitutes a bench mark of the Southern Pacific Railway. M 7 . — At Rye Patch, Humboldt County, Nev., 30 meters north of mile pole 366, 49 meters north of the Southern Pacific Railway track, 35 meters south of the line fence, 20 meters east of the freight house. Note 11A.* N 7 (S. P.). — 0.6 mile west of Rye Patch, Humboldt County, Nev., at railroad mileage 365.4, in the top surface of the south headwall of concrete culvert No. 365C. It is the top of a round-headed iron bolt and constitutes a Southern Pacific Railway bench mark. 7 (S. P.). — 2 miles east of Zola, Humboldt County, Nev., in the top surface of the south headwall of culvert No. 363C. It is the top of a round-headed iron bolt and constitutes a Southern Pacific Railway bench mark. P 7 . — 0.3 mile east of Zola, Humboldt County, Nev., at railroad mileage 361.7, 46 meters south of the Southern Pacific Railway track, 1 meter north of the south line fence. Note 11A.* Q 7 . — At Oreana, Humboldt County, Nev., at railroad mileage 357.9, on the top surface of the southeastern one of the four central pillars under the Southern Pacific Railway water tank. Note 1.* R,. — At Woolsey, Humboldt County, Nev., at railroad mileage 353.6, 150 meters west of the east end of the siding, on the top surface of the south headwall of stone culvert 353D, 10 meters south of the Southern Pacific Railway track, and about 1 meter below it. Note 1.* S 7 . — At Kodak, Humboldt County, Nev., opposite the station sign, on the south side of the Southern Pacific Railway track, 100 meters west of mile pole 349, 1 meter north of the south line fence. Note 11A.* T 7 . — 2.5 miles east of Lovelocks, Humboldt County, Nev., 0.5 meter north of mile pole 347, 16.5 meters north of the Southern Pacific Railway track. Note 11A.* U 7 . — 2 miles east of Lovelocks, Humboldt County, Nev., at railroad mileage 346.4, on the south end of the east abut- ment of Southern Pacific Railway bridge 346B over the irrigation canal. Note 1.* V 7 . — At Lovelocks, Humboldt County, Nev., 50 meters east of the station, on the north side of the northwestern one of the concrete pillars under the Southern Pacific Railway water tank, 60 meters south of the track. Note 1.* W 7 . — At Perth, Humboldt County, Nev., opposite the station sign at railroad mileage 340.5 in the second line of telegraph poles, 30 meters south of the Southern Pacific Railway track. Note 11A.* X 7 . — At Granite Point, Humboldt County, Nev., 20 meters west of mile pole 336, at the edge of a hummock, 100 meters west of the section foreman's house, 60 meters north of the Southern Pacific Railway track, 2.5 meters south of the line fence. Note 11A.* Y 7 . — At Toulon, Humboldt County, Nev., at railroad mileage 331.8, 11.4 meters north of the station sign, 18.5 meters north of the Southern Pacific Railway track, in the first line of telegraph poles. Note 11A.* Z 7 . — At Toy, Humboldt County, Nev., 30 meters west of the station, 28.5 meters north of the Southern Pacific Railway track, 0.9 meter outside of the west fence inclosing the section foreman's house, 9.6 meters north of the south- west angle of the inclosure. Note 11A.* A 8 . — At Miriam, Churchill County, Nev., 6.6 meters east of the station, at railroad mileage 324.2, 29 meters south of the Southern Pacific Railway track, 0.8 meter west of a telegraph pole in the second line of poles. Note 11A.* B 8 . — 1 mile east of Huxley, Churchill County, Nev., at mileage 317.6 of the Southern Pacific Railway, on the east abutment of bridge 317A. Note 1.* C g . — At Parran, Churchill County, Nev., on the south side of the southwest concrete pillar under the Southern Pacific Railway water tank. Note 1.* D 8 (S. P.). — 1.5 miles east of Desert, Churchill County, Nev., at railroad mileage 308.4, in the top surface of the concrete abutment of the small Southern Pacific Railway bridge. It is the top of a round-headed bolt and constitutes a Southern Pacific Railway bench mark. E 8 . — 0.9 mile west of Desert, Churchill County, Nev., 1 meter north of mile pole 306, 18.8 meters north of the South- em Pacific Railway track, 50 meters east of the "distant" signal. Note 11 A.* F,(S. P.). — At Upsal, Churchill County, Nev., at Southern Pacific Railway mileage 303.6, 200 meters east of the 1 mile sign at the east side of Upsal, in concrete culvert No. 303A. It is the top of a round-headed iron bolt and con- stitutes a Southern Pacific Railway bench mark. * See p. 48. PRECISE LEVELING, BKIGHAM TO SAN FRANCISCO. 55 G 8 . — At Upsal, Churchill County, Nev., 150 meters west of the station, on the top surface of the east abutment of the small Southern Pacific Railway bridge No. 301A, 2 meters south of the track and about 0.6 meter below it. Note 1.* H 8 (S. P.). — 1.2 miles east of Falais, Churchill County, Nev., in the top surface of the west concrete abutment of the small Southern Pacific Railway bridge 299A. It is the top of a round-headed iron bolt and constitutes a Southern Pacific Railway bench mark. I 8 . — At Massie, Churchill County, Nev., at Southern Pacific Railway mileage 293.2, 0.3 mile east of the east end of the siding, on the top surface of the east abutment to bridge 293A. Note 1.* J„. — At Massie, Churchill County, Nev., at Southern Pacific Railway mileage 291.7, 0.3 mile west of the west end of the siding, on the top surface of the east abutment to Southern Pacific Railway bridge 291A. Note 1.* K 8 (S. P.). — At Hazen, Churchill County, Nev., 100 meters east of the cast end of the siding, on the top surface of the east abutment of Southern Pacific Railway bridge 289A. It is the top of a round-headed iron bolt and constitutes a Southern Pacific Railway bench mark. Lg. — At Hazen, Churchill County, Nev., 0.3 mile east of the station, in the southeast concrete pillar under the Southern Pacific Railway water tank, 50 meters north of the track. Note 1.* M 8 . — At Patna, Churchill County, Nev., at railroad mileage 284.7, 0.1 mile west of the section foreman's house, on the top of the west concrete abutment of the small Southern Pacific Railway bridge 284B. Note 1.* N 8 (S. P.). — In Lyon County, 1.1 miles west of Patna, Churchill County, Nev., at railroad mileage 282.8, in the top surface of the west abutment of small Southern Pacific Railway bridge 282C. It is the top of a round-headed iron bolt and constitutes a Southern Pacific Railway bench mark. O s (S. P.). — 0.5 mile east of Argo, Lyon County, Nev., at railroad mileage 281.4, in the east concrete abutment to bridge 281B. It is the top of a round-headed iron bolt and constitutes a Southern Pacific Railway bench mark. P 8 . — At Argo, Lyon County, Nev., 0.1 mile east of the station sign, at railroad mileage 280.5, 11.3 meters east of the derailing switch, 30.7 meters north of the Southern Pacific Railway track, and 0.4 meter south of the north line fence. Note HA.* Qg. — At Luva, Lyon County, Nev., at railroad mileage 277.8, 4 meters east of the station sign, 29.5 meters north of the Southern Pacific Railway track, 1 meter south of the north line fence, and 16 meters west of the point of the branch line. Note 11A.* Rg. — At Fernley, Lyon County, Nev., at railroad mileage 276.1, 16 meters west of the Southern Pacific Railway station, 59 meters north of the track, 0.8 meter south of the north line fence. The station is soon to be moved about 0.3 mile to the westward. Note 11A.* Sg. (U. S. G. S.). — At Fernley, Lyon County, Nev., 200 meters west of the Southern Pacific Railway station, 60 meters west of mile pole 276, 3 meters south of the track, on the south headwall of a concrete culvert. The station is soon to be moved about 0.3 mile to the westward. Note 17* not stamped. T 8 . — At Gilpin, Washoe County, Nev., 150 meters west of the Southern Pacific Railway water tank, 200 meters east of the station sign, and 15.7 meters south of the track. Note 11A.* U 8 (S. P.). — At Derby, Washoe County, Nev., at railroad mileage 269.5, in the top surface of the west abutment of Southern Pacific Railway bridge No. 13 over the Truckee River. It is the top of a round-headed iron bolt and constitutes a Southern Pacific Railway bench mark. V 8 (S. P.). — 0.6 mile west of Derby, Washoe County, Nev., at railroad mileage 268.7, in the top surface of the east abutment of Southern Pacific Railway bridge No. 12 over the Truckee River. It is the top of a round-headed iron bolt and constitutes a Southern Pacific Railway bench mark. W 8 (S. P.). — 1 mile west of Derby, Washoe County, Nev., at railroad mileage 268.2, in the top surface of the east abutment of Southern Pacific Railway bridge No. 11 over the Truckee River. It is the top of a round-headed iron bolt and constitutes a Southern Pacific Railway bench mark. X 8 (S. P.). — AtThisbe, Washoe County, Nev., atrailroad mileage 264. 7,0. 2milewestof the Derby Dam of the United States Reclamation Service, in the top surface of the east concrete abutment of Southern Pacific Railway bridge No. 10 over the Truckee River which goes under the bridge from north to south. It is the top of a round-headed iron bolt and constitutes a Southern Pacific Railway bench mark. Y 8 (S. P.). — At Thisbe, Washoe County, Nev., 0.5 mile west of the Derby Dam of the United States Reclamation Service at railroad mileage 264.5, in the top surface of the east abutment of Southern Pacific Railway bridge No. 9 over the Truckee River. The river goes under the bridge from south to north. It is the top of a round-headed iron bolt and constitutes a bench mark of the Southern Pacific Railway. Z 8 (S. P.). — At Clark, Storey County, Nev., 100 meters east of the east end of the siding, in the top surface of the west concrete abutment of Southern Pacific Railway bridge No. 8 over the Truckee River. It is the top of a round- headed iron bolt and constitutes a railroad bench mark. A 9 (S. P.). — One-half mile east of Ditho, Washoe County, Nev., at railroad mileage 258.1, in the top surface of the east abutment of Southern Pacific Railway bridge No. 7 over the Truckee River. It is the top of a round-headed iron bolt and constitutes a railroad bench mark. B, —At Hqfed, Washoe County, Nev., at railroad mileage 253.1, 40 meters east of the station sign, 29.4 meters south of the Southern Pacific Railway track, on top of a large black bowlder 3 meters high. Note 1.* C 9 (S. P.).— Near Vista, Washoe County, Nev., at railroad mileage 251, on the top surface of the east abutment of Southern Pacific Railway bridge No. 6 over the Truckee River. It is the top of a round-headed iron bolt and consti- tutes a railroad bench mark. * Seo p. 48. 56 U. S. COAST AND GEODETIC SURVEY SPECIAL PUBLICATION NO. 22. D„ (S. P.).— InStorey County, 1.4 miles east of Vista, Washoe County, Nev., on the west abutment of the small South- em Pacific Railway bridge 250B. It is the top of a round-headed iron bolt and constitutes a railroad bench mark. E 9 (S. P.).— InStorey County, 0.6 mile east of Vista, Washoe County, Nev., at railroad mileage 249.8, on the top sur- face of the east abutment of Southern Pacific Railway bridge No. 5 over the Truckee River. It is the top of a round- headed iron bolt and constitutes a railroad bench mark. F„. — At Vista, Washoe County, Nev., 10.6 meters south of mile pole 249, 25.2 meters south of the Southern Pacific Railway track, 0.2 mile west of the station sign, in the angle formed by the fence at the grade crossing with the south line fence, northwest of the highway. Note 11A.* G„. — At Sparks, Washoe County, Nev., at railroad mileage 246.3, 250 meters west of the Southern Pacific Railway station, in the angle formed by the high board fence at the grade crossing, 1 meter from fence corner, 14.9 meters north of the track. Note 11A.* H 9 . — At Reno, Washoe County, Nev., a brass plate 2 by 4 inches in the granite top of the north balustrade of the east entrance to the city hall. The elevation marked on top is 96.72 feet above the zero of the city system of levels. I„ (U. S. G. S.). — At Reno, Washoe County, Nev., on the main building of the Nevada State University in the side of the northeast corner stone. Note 17* stamped 4554.817. J 9 . — At Lawton, Washoe County, Nev., 0.3 mile east of the Southern Pacific Railway station, 120 meters east of mile pole 238, on top of a large brown bowlder 1.5 meters high, 15 meters north of the westbound track. Note 1.* K,. — 2 miles east of Verdi, Washoe County, Nev., at mileage 234.1 on the old line of the Southern Pacific Railway, on the east abutment of Southern Pacific Railway bridge No. 4 on the Truckee River. Note 1*. L 9 (S. P.). — At Verdi, Washoe County, Nev., the top of the western inside base bolt of signal tower 2329, which is the "distant" signal for the east end of Verdi siding. It constitutes a Southern Pacific Railway bench mark. DESCRIPTIONS OF PERMANENT BENCH MARKS BETWEEN MARMOL, NEV., AND SAN FRANCISCO, CAL., 1912. F e . — At Marmot, Washoe County, Nev., at Southern Pacific Railway mileage 230.5, in the cow pasture opposite a large red building, 75 meters south of the track, 20 meters west of the east pasture fence, 7 meters north of the south pasture fence, 100 meters east of bench mark E 6 , in the top of a black bowlder. The bench mark is the top of a round- headed iron bolt. E 6 . — At Marmot, Washoe County, Nev., at Southern Pacific Railway mileage 230.5, in the cow pasture opposite a large red building, 65 meters south of the track, 60 meters east of the west pasture fence, 10 meters north of the south pasture fence, on the top of a large bowlder. Note 1.* D 6 . — About 0.6 mile southwest of Marmol, Washoe County, Nev., on the top of the east abutment of the Southern Pacific Railway bridge over the Truckee River. Note 1.* Y 10 . — At Calvada, Surra County, Cat., 5 meters west of the California-Nevada State line, on the top of the north headwall of the stone culvert under the Southern Pacific Railway tracks, and about 1.2 meters below them. Note 1.* X I0 . — At Mystic, Nevada County, Cat., 65 meters east of the Southern Pacific Railway station, at railroad mileage 225.8, on the top of the concrete culvert under the track. Note 1.* W, . — At Iceland, Nevada County, Cal., on the top of the east stone abutment of Southern Pacific Railway bridge No. 220G over the Truckee River. Note 1.* V 10 . — Near Prosser Creek, Nevada County, Cat., 0.5 mile west along the Southern Pacific Railway track from the bridge over Prosser Creek, on top of a large volcanic bowlder. Note 1.* U 10 . — At Truckee, Nevada County, Cal., 30 meters west of the Southern Railway passenger station, on the top surface of the northwestern one of the four central pillars under the water tank, about 1.2 meters above the rail. Note 1.* T I0 .— At Tunnel, Placer County, Cal., 0.4 mile east of the Southern Pacific Railway station (tunnel 13), 150 meters east of the east end of thesnowshed, on the top of the south headwall of stone culvert No. 201F, under the track. Note 1.* S 10 . — About i mile east of Eder, Placer County, Cal., 15 meters west of Southern Pacific Railway mile pole 198, 100 meters west of the east end of the siding, in the snowshed on the inside of the stone retaining wall, about 1 meter above the track. Note 1.* R, . — At Summit {Donner post office), Placer County, Cal., on the front wall of the concrete Southern Pacific Rail- way station, between two front windows, about 1.2 meters above the track. Note 1.* Q 10 . — 0.5 mile west of Spruce, Nevada County, Cal. , on the top of the granite abutment of the Southern Pacific bridge, south of the track, and about 0.6 meter below it. Note 1.* P 10 .— At Cisco, Placer County, Cal., on top of a large bowlder 50 meters west of the Southern Pacific Railway Station, 10 meters north of the snowshed, about 1.5 meters below the track. Note 1.* O 10 .— At Emigrant Gap, Placer County, Cal., on top of a large flat bowlder 3 meters east of the Southern Pacific Railway station, 2 meters outside of the snowshed on the south side of the track, and about 0.6 meter above the track. Note 1* N 10 . — At Blue Canyon, Placer County, Cal., on the face of the concrete drinking fountain, at the Southern Pacific Railway station, about 1.2 meters above the track. Note 1.* M 10 . — At Orel, Placer County, Cal., 200 meters east of the Southern Pacific Railway station, on the top surface of the central concrete pillar under the water tank, about 0.3 meter above the track. Note 1.* * See p. 48. PRECISE LEVELING, BRIGHAM TO SAN FRANCISCO. 57 L, . — At Towle, Placer County, Cal. , 0.3 mile east of the Southern Pacific Railway station, 90 meters east of mile pole 158, on the top of a bowlder 1 meter high, 20 meters north of the track, and about 1.5 meters above it. Note 1.* K 10 . — At Gold Run, Placer County, Cal., 0.6 mile west of the Southern Pacific Railway passenger station, on the top surface of the south headwall of concrete culvert No. 152D, under the Southern Pacific track, 3.2 meters south of the track, and about 0.6 meter below it. Note 1.* J I0 . — 0.3 mile southwest of Wirt, Placer County, Cal., on the top of the east concrete abutment to Southern Pacific Railway bridge, about 0.6 meter below the track. Note 1.* I 10 . — At Colfax, Placer County, Cal., on the top surface of the concrete slab in front of the drinking fountain at the Nevada County exhibit. Note L* H 10 . — At Lander, Placer County, Cal., on top of the central concrete pillar under the Southern Pacific Railway water tank, 4J meters abovo the track. Note 1.* G, . — One mile northeast of Clippergap, Placer County, Cal., about 1.2 meters from the east end of tunnel O of the westbound line of the Southern Pacific Railway, on the south stone wall, 0.6 meter above the top of the rail. Note 1.* F 10 . — 0.2 mile east of the Southern Pacific Railway station at Clippergap, Placer County, Cal., on top of the old foun- dation of the water tank (now removed), about 0.5 meter below the top of the rail. Note 1.* E 10 . — At East Auburn, Placer County, Cal., opposite the Southern Pacific Railway passenger and freight station, on the old line (now the westbound line) of the Southern Pacific Railway, on the eastern one of the two northwestern concrete pillars under the water tank, about 1 meter above the top of the rail. Note 1.* D 19 . — About 0.2 mile east of Newcastle, Placer County, Cal. , at the west end of the Southern Pacific Railway tunnel, north of the track, on the top surface of the bottom stone of the tunnel, 0.3 meter above the track. Note 1.* C, .- — About 0.5 mile east of Rochlin, Placer County, Cal., on the west side of the concrete bridge of the Southern Pacific Railway, which carries the eastbound track over the westbound track; north of the westbound track and about 1 meter above it, about 0.46 meter from the north edge of the pier, and 1.5 meters above the ground. Note 1.* B 10 . — Near Roseville, Placer County, Cal., about 0.8 mile east of the Southern Pacific Railway station, on the top surface of the granite abutment at the east end of Southern Pacific Railway bridge 107D, on the south side of track, and about 0.5 meter below it. Note 1.* A, . — At Roseville, Placer County, Cal., on the top surface of the concrete base of signal tower 1067, 70 meters west of the Southern Pacific Railway station; 10 meters north of the track, and about 0.6 meter above it. Note 1.* Z 9 (U.S.G.S.). — About 2 miles northeast of Antelope, Sacramento County, Cal., at a highway crossing, north of the Southern Pacific Railway track, 7 meters south of the north line fence, 1.6 meters from a fence located 18 meters north of the track, and about 3 meters above the track. Note 18,* stamped 146. Y . — At Antelope, Sacramento County, Cal., 90 meters west of the Southern Pacific Railway station, on the top sur- face of the north headwall of the stone culvert under the Southern Pacific tracks, about 1.2 meters below the track. Note 1.* X„. — 1.2 miles northeast of Benali, Sacramento County, Cal., on the top surface of the stone abutment at the east end of the Southern Pacific Railway steel bridge No. 96C, about 0.6 meter below the track. Note 1.* W„. — At Elvas, Sacramento County, Cal., at mile pole 92, 0.4 mile north of Elvas tower, on the top of the south concrete abutment of the Southern Pacific Railway steel bridge over the American River, east of the track, and 2.5 meters below the top of the rail. Note 1.* V„. — At Brighton, Sacramento County, Cal., 100 meters east of the station, on the top surface of the southwestern one of the four pillars under the Southern Pacific Railway water tank, about 3.4 meters above the ground. Note 1.* TJ 9 (TJ. S. G. S.). — About 0.8 mile north of Florin, Sacramento County, Cal., at mile pole 130, on the right of way of the Southern Pacific Railway, east of the track; 0.5 meter west of the east fence line. Note 18* stamped "36 B." T, (U. S. G. S.). — About 3 miles south of Florin, Sacramento County, Cal., at Southern Pacific Railway mile pole 126, north of the highway crossing, east of the track, 10 meters south of the angle of the fence. Note 18* stamped "37 B." S, (U. S. G. S.). — At Elk Grove, Sacramento County, Cal., at the southwest corner formed by the Southern Pacific right of way with the main street of Elk Grove, west of the track, opposite the north end of the Southern Pacific Rail- way station between two poles set about 2.5 meters apart. Note 18* stamped "49 B." R 8 (U. S. G. S.). — At McConnell, Sacramento County, Cal., 0.2 meter northeast of the northeast corner of the small house, between the Southern Pacific Railway track and the county road. Note 18* stamped "46 B." Q,. — At Need, Sacramento County, Cal., 375 meters south of the station sign, 30 meters south of mile pole 115, on the top of the north concrete abutment to the Southern Pacific Railway bridge, about 0.3 meter below the track. Note 1* P„. (U. S. G. S.).— At Gait, Sacramento County, Cal., on the right of way of the Southern Pacific Railway, in line with the north end of the railway station; 13.1 meters west of the main line, 0.6 meter from the northwest corner of the grass park. Note 18* stamped "46 B." 0„ (U. S. G. S.).— At Jahant, San Joaquin County, Cal., 8 meters south of mile pole 108, on the Southern Pacific Railway right of way, at crossing 107F; 0.9 meter north of the north highway fence, 11.3 meters east of the track. Note 18* stamped "48 B." N,. — 1 mile north of Acampo, San Joaquin County, Cal., on the top surface of the north concrete abutment of Southern Pacific Railway bridge No. 107D, about 0.6 meter below the top of the rail. Note 1.* * See p. 48. 58 U. S. COAST AND GEODETIC SURVEY SPECIAL PUBLICATION NO. 22. M 9 (U. S. G. S.). — 1 mile south of Acampo, San Joaquin County, Cal., at crossing 105A, in the north margin of the road, 16 meters east of the Southern Pacific Railway track, 6.4 meters south of the north crossing fence. Note 18* stamped "53 B." L 9 . — At Lodi, San Joaquin County, Cal., 200 meters north of the Southern Pacific Railway station in the east face of the northeast pillar under the water tank. Note 1.* K 9 (U. S. G. S.). — li miles south of Lodi, San Joaquin County, Cal., 75 meters south along the track from mile pole 102, in the edge of a cultivated field, 16.3 meters east of the Southern Pacific Railway track, 0.9 meter east of the fence corner at the crossing north of the road, about 1.2 meters below the track. Note 18* stamped "45 B." J 9 (U. S. G. S.). — At Pearson, San Joaquin County, Cal., 7.7 meters north along the track from mile pole 99 on the right of way of the Southern Pacific Railway, 0.3 meter west of the east line fence, 4.8 meters east of the track, and about 1 meter below it. Note 18* stamped "37 B." I 9 . — 1.2 miles north of Hammer, San Joaquin County, Cal., at railroad mileage 96.8, in the west headwall of con- crete culvert 96B, under the Southern Pacific Railway track. Note 1.* H 9 (U. S. G. S.). — One-half mile north of Hammer, San Joaquin County, Cal., 11.8 meters north along the track from mile pole 96, on the right of way of the Southern Pacific Railway, 0.8 meter west of the east line fence, 15 meters east of track, and about 1 meter below it. Note 18* stamped "28 B." G 9 . — 0.8 mile north of El Pinal, San Joaquin County, Cal., in the north abutment of bridge 93A, west of the Southern Pacific Railway track, about 0.6 meter below the top of the rail. Note 1.* F 9 (U. S. G. S.). — About 2 miles north of Stockton, San Joaquin County, Cal., 10 meters north along the track from mile pole 93, 0.5 meter west of the east line fence on the right of way of the Southern Pacific Railway, 15.7 meters east of the track, and about 1 meter below it. Note 18* stamped "20 B." E 9 . — At Stockton, San Joaquin County, Cal., in the Western Pacific Railway station, in the west side of the south- west pillar of the portico at the south end. Note 1.* D 9 . — At Stockton, San Joaquin County, Cal., in the top of the concrete curbing around a palm tree, in the passage- way between the Southern Pacific Railway waiting room and baggage room. Note 1.* C 9 .— About 2 miles south of Stockton, San Joaquin County, Cal., in the east headwall of concrete culvert No. 87B under the Southern Pacific Railway track, 140 meters north of the Western Pacific Railway crossing, about 0.6 meter below the track. Note 1.* B 9 (U. S. G. S.). — About 1 mile north of French Camp, San Joaquin County, Cal., 0.6 meter east of Southern "Pacific Railway mile pole 87, 1 meter below the track. Note 18* stamped "15 B." This bench mark of the United States Geological Survey, the position of which was originally published as 8 feet south of mile post 88, was found washed out and relocated as described above. A 9 . — About 0.7 mile north of French Camp, San Joaquin County Cal., at railroad mileage 86.7, on the east head- wall of concrete culvert No. 86C of the Southern Pacific Railway, about 0.6 meter below the track. Note 1.* Z 8 . — Near French Camp, San Joaquin County, Cal., in the east headwall of concrete culvert 84A under the South- ern Pacific Railway track. Note 1.* Y 8 (U. S. G. S.). — Near Lathrop, San Joaquin County, Cal., 40 meters south along the track from Southern Pacific Railway mile pole 84, 0.6 meter south of the north highway fence at the crossing, 11.5 meters east of the Southern Pacific northbound track. Note 18* stamped "19 B." X 8 . — At Lathrop, San Joaquin County, Cal., 100 meters north of the Southern Pacific Railway station in the south- east pillar of the water tank. Note 1.* W 8 (U. S. G. S.). — At Lathrop, San Joaquin County, Cal., about 75 meters north of the Southern Pacific Railway station, west of the tracks, at the fence line, 15 meters Bouth of the water tank. Note 18* stamped "20 B." V 8 . — Near Lathrop, San Joaquin County, Cal., at railroad mileage 78.1, at the west end of the viaduct leading to the west end of the Southern Pacific Railway bridge 78B over the San Joaquin River, on the top surface of the bearing stone of the northwest pier, about 1.8 meters below the top of the rail. Note 1.* U 8 . — 1 mile northeast of Banta, San Joaquin County, Cal., in the top surface of the east abutment to Southern Pacific Railway bridge 74C, south of the track. Note 1.* T 8 (U. S. G. S.). — At Banta, San Joaquin County, Cal., opposite mile pole 74 on the Southern Pacific Railway right of way, 250 meters east of the Southern Pacific station. Note 18* stamped "22.121. " S 8 . (U. S. G. S.). — At Tracy, San Joaquin County, Cal., about 0.3 mile east of the Southern Pacific Railway station 2 meters north of mile pole 71, 0.3 meter south of the line fence on the right of way of the Southern Pacific Railway. Note 18* stamped " 53.927. " Rg. — At Tracy, San Joaquin County, Cal., 150 meters east of the Southern Pacific Railway station, in the top sur- face of the southwest concrete pillar under the water tank. Note 1.* Q 8 . — At Tracy, San Joaquin County, Cal., 75 meters west of the Southern Pacific Railway station, in the north face of the northwest concrete pillar under the water tank. Note 1.* P 8 (U. S. G. S.). — Near Tracy, San Joaquin County, Cal., 10 meters along the track east of mile pole 68, on the Southern Pacific Railway right of way, 1 meter from the south line fence, about 1 meter below the track. Note 18* stamped "102.656". 8 (U. S. G. S.). — At Midway, Alameda County, Cal., about 1.5 meters east of mile pole 63, about 150 meters east of the station on the south side of the track on the Southern Pacific Railway right of way. Note 18* stamped ' '351.341. " *See p. 48. PRECISE LEVELING, BRIGHAM TO SAN FRANCISCO. 59 N 8 . — Near Midway, Alameda County, Cal., in the concrete base of Southern Pacific Railway signal tower 625. Note 1.* M 8 . — Near Cayley, Alameda County, Cal., 100 meters west of Southern Pacific Railway mile pole 60, 125 meters of the east end of Cayley siding, in the face of a rocky cut, about 1.2 meters above the track. Note 1.* L 8 . — Near Altamont, Alameda County, Cal., at Southern Pacific railway mileage 57.9, on the north side at the east entrance to Southern Pacific tunnel No. 1, about 0.2 meter from the end of tunnel and 1 meter above the track. Note 1.* K 8 . — One-half mile east of Altamont, Alameda County, Cal., on the south abutment to the Western Pacific Rail- way crossing over the Southern Pacific track, about 1 meter above the Southern Pacific track. Note 1.* J 8 (U. S. G. S.). — At Altamont, Alameda County, Cal., about 60 meters east of the Southern Pacific Railway sta- tion, between the Southern Pacific main track and the county pike, abreast of the derailing switch to the siding. Note 18* stamped ' '739.899. " I 8 . — Near Altamont, Alameda County, Cal., at Southern Pacific Railway mileage 53.7, on the south headwall of Southern Pacific culvert 53G, about 0.6 meter below the track. Note 1*. H 3 . — Near Livermore, Alameda County, Cal., at Southern Pacific Railway mileage 52.2, on the north abutment of the overhead crossing of the Western Pacific Railway over the Southern Pacific Railway, about 1.2 meters above the Southern Pacific track. Note 1.* G 8 . — About 2 miles east of Livermore, Ulameda County, Cal., at Southern Pacific mileage 49.1 on the south abut- ment of the overhead crossing of the Western Pacific Railway over the Southern Pacific Railway, about 1 meter above the Southern Pacific track. Note 1.* F 8 (U. S. G. S.). — At Livermore, Alameda County, Cal., on the Farmers' Union Building, which is the large build- ing just east of the Southern Pacific Railway station, north of the track, in the south side wall at the southeast corner of the building. Note 17* stamped "488." E 8 . — About 1 mile west of Livermore, Alameda County, Cal., south of Southern Pacific Railway bridge No. 45A, north of the highway, about 30 meters east of the water tank, on top of the wall to the west abutment of the highway bridge. Note 1.* D 8 .- — At Radum, Alameda County, Cal., about 1 mile east of Pleasanton, 0.1 mile east of the signal tower, on the east abutment of the Southern Pacific Railway concrete bridge No. 42A, south of the track, and about 3 meters east of the derailing switch. Note 1.* C 8 .- — At Pleasanton, Alameda County, Cal., \ mile west of the Southern Pacific Railway station, on the south head- wall of highway culvert at Southern Pacific Railway bridge 40C, about 3 meters north of the track and 0.18 meter above the top of the rail. Note 1.* B 8 . — At Verona, Alameda County, Cal., 90 meters west of the Southern Pacific Railway station, 23 meters east of the highway crossing, in the west abutment of the Western Pacific Railway overhead crossing, about 6 meters from the east edge of the abutment and 0.6 meter above the Southern Pacific track. Note 1.* A 8 . — At Brightside, Alameda County, Cal., about 200 meters east of the station at mileage 34.9 on the Southern Pacific Railway, north of the track on the east abutment of the Western Pacific Railway bridge over Alameda Creek. Note 1.* Z 7 (U. S. G. S.). — At Farwell, Alameda County, Cal., about 60 meters east of the Southern Pacific Railway station, 12 meters north of the track. Note 18* stamped ' '167.099. " Y 7 . — About 1 mile east of Niles, Alameda County, Cal., east of the track, on the north end of Southern Pacific Railway bridge No. 30D over Alameda Creek. Note 1.* X 7 . — At Niles, Alameda County, Cal., about 60 meters west of the railway station, on the southern one of the two easternmost pillars under the wooden water tank. Note 1.* W 7 . — At Niles, Alameda County, Cal., one-half mile south of the railway station, about 9 meters north of the cross- ing of the Southern Pacific and Western Pacific Railways, east of the track, on top of rock abutment of Southern Pacific Railway bridge over the river. Note 1.* V 7 . — At Irvington, Alameda County, Cal., about 90 meters north of the Southern Pacific Railway station, on the west headwall of culvert under the tracks. Note 1.* U 7 . — Near Warmsprings, Alameda County, Cal., on the west headwall of culvert 34E under the Southern Pacific Railway track. Note 1.* T 7 . — At Warmsprings, Alameda County, Cal., about 90 meters north of the Southern Pacific Railway station, on the west headwall of culvert 36B under the crossing of the track and the highway. Note 1.* Sj. — Near Warmsprings, Alameda County, Cal., in the west headwall of culvert 38A under the Southern Pacific Railway track, and about 0.6 meter below it. This benchmark has probably been destroyed or moved. Note 1.* R 7 . — Near Milpitas, Santa Clara County, Cal., at Southern Pacific Railway mileage 39.9, in the top surface of the west headwall of the culvert under the county road, about 24 meters east of the track and about 1 meter above the county road. Note 1.* Q 7 .— Near Wayne, Santa Clara County, Cal., at mileage 43.9 of the Southern Pacific Railway, in the top of the south abutment to bridge 43G, east of the track and about 0.5 meter below it. Note 1.* P 7 (U. S. G. S.).— At San Jose, Santa Clara County, Cal., on the north balustrade of the east entrance to the Hall of Records, about 1.5 meters above the ground. Note 17* stamped "98 S. F." * See p. 48. 60 U. S. COAST AND GEODETIC SUEVEY SPECIAL PUBLICATION NO. 22. 7 . — At San Jose, Santa Clara County, Cal., just west of the Southern Pacific Railway station, south of the tracks, in the northwestern one of the four central pillars under the Southern Pacific water tank. Note 1.* N 7 . — At Santa Clara, Santa Clara County, Cal., north of Southern Pacific Railway station, in the south end of the large grass park. Note 11A.* M 7 . — At Lawrence, Santa Clara County, Cal., opposite the Southern Pacific Railway station, on the right of way, 40.9 meters north of the track, 1.9 meters from the line fence, 8.9 meters west of the road fence. Note 11A.* L 7 . — At Sunnyvale, Santa Clara County, Cal., in the east end of the grass park which lies northwest of the Southern Pacific Railway station. Note 11A.* K 7 . — At Mountain View, Santa Clara County, Cal., north of the Southern Pacific Railway station, in the south side of the northern one of the two circular grass parks. Note 11A.* J 7 . — At Mayfield, Santa Clara County, Cal., in the south end of the small grass park, north of the Southern Pacific Railway station, and west of the track. Note 11A.* I 7 . — At Palo Alto, Santa Clara County, Cal., in the north end of the small grass park east of the Southern Pacific Railway, and south of University Avenue. Note 11A.* H 7 . — In San Mateo County near Palo Alto, Santa Clara County, Cal., west of the track, on the top surface of the stone abutment at the north end of the Southern Pacific Railway bridge over San Francisquito Creek, which forms the boundary between San Mateo and Santa Clara Counties. Note 1.* G 7 . — At Menlo Park, San Mateo County, Cal., on the opposite side of the alley from the Oak Grove Villa Hotel, in the top of a concrete sphere on a corner post, about 1.2 meters above the ground. Note 1.* F 7 . — At Redwood City, San Mateo County, Cal., north of the Southern Pacific Railway station, in the north corner of the triangular grass park. Note 11A.* E 7 .— At San Carlos, San Mateo County, Cal., On the Southern Pacific Railway station, in the east side of the eastern stone post that supports the roof over the passage way, about 0.23 meter above the pavement. Note 1.* D 7 . — At Belmont, San Mateo County, Cal., north of the Southern Pacific Railway station, in the south end of the grass park, midway between the rail and the fence. Note 11A.* C 7 . — At Beresford, San Mateo County, Cal., about 300 meters north of the Southern Pacific Railway station, in the concrete foundation of signal tower 202, west of the track. Note 1.* B 7 . — At San Mateo, San Mateo County, Cal., in the top of the concrete wall at the east entrance to the small park at the Southern Pacific Railway passenger station, about 0.3 meter north of the north pillar. Note 1.* A 7 . — At San Mateo, San Mateo County, Cal., on Ellsworth Avenue about one-half mile north of the Southern Pacific Railway station, in the south side of the F. A. M. building, about 3 meters from the southeast corner and about 1 meter above the ground. Note 1.* Z 6 . — At Burlingame, San Mateo County, Cal., in the foundation on the east side of the Southern Pacific Railway station, in front of the ticket window, about 0.15 meter above the pavement. Note 1.* Y„. — At Millbrae, San Mateo County, Cal., in the east wall of the power substation, about 1 meter from the northeast corner and about 1.5 meters above the brick pavement. Note 1.* X 6 . — At San Bruno, San Mateo County, Cal., about 15 meters northeast of the Southern Pacific Railway station, the top of the southern inside base bolt of signal tower 108. W„. — At Holy Cross, San Mateo County, Cal., north of the stone building at the entrance to Holy Cross Cemetery, between the Southern Pacific Railway track and the street, on the eastern side of a large conical rock, on the east side of the fountain. Note 1.* City 418. — At San Francisco, San Francisco County, Cal., on the north side of Sickles Avenue about 35 meters west of Huron Avenue and just to the left of the entrance to No. 110 Sickles Avenue. The bench mark is a cross on the cement surface at the west end of an iron gateway. City 386. — At San Francisco, San Francisco County, Cal. , on the south side of Ocean Avenue about 12 meters east of San Jose Avenue. The bench mark is a cross at the west end of the bottom step to the side entrance to a saloon. City 640. — At San Francisco, San Francisco County, Cal., at the intersection of San Jose, Circular, and Joost Avenues. The bench mark is a cross at the southeast corner rail guard around the Southern Pacific Railway gate post, about 1 meter above the ground. City 635. — At San Francisco, San Francisco County, Cal., on the north side of Bosworth Street opposite Lyell Street. The bench mark is a cross on the head of an iron spike embedded in the top of the dome at the east end of the east concrete retaining wall at the entrance to the culvert under the Southern Pacific Railway viaduct. * See p. 48. PRECISE LEVELING, BRIGHAM TO SAN FRANCISCO. 61 - "V •4 -"•* t "5 5 ^ £ ^f f v ^-A ^/^S^ ^N + ^, h S ;7o vTK £ ■f r & '*-■+ o~~ o ° r <~— £T^ H / X < s-Hj)'bi- \ V Y* ^^ Ui z r \ W ^^^) < \ 1 * < 4. ^» * -. +JT o s\v / *K W v. ^ ^ Y^ •J . * v ~ i «¥ ts O 1 S ? /^ s *~ O j ' 4- o o Z j i - / UJ N + + o 1 _ i **- t * ° / i * / i + i J ^J* ^ \*— i i 1 ^* tj^y 1 r^\- 1 N 9/ ^r~J } 1 C o c £ CD Z UJ > UJ fi iE < o < a o z o X LO Q. < 2 62 U. S. COAST AND GEODETIC SURVEY SPECIAL PUBLICATION NO. 22. PRECISE LEVELING, BKIGHAM TO SAN FRANCISCO. 63 64 U. S. COAST AND GEODETIC SURVEY SPECIAL PUBLICATION NO. 22. PBECISE LEVELING, BEIGHAM TO SAN FRANCISCO. 65 o 55 -S + < 1 t. JL 2 1 0) ■ E o + + I < < I (T m Q 2 < > Ld Z z" O _J ui z Ld Ld LU m < o m u. o z o H < c_> o + V* 53167°— 14- INDEX TO ELEVATIONS AND DESCRIPTIONS OF BENCH MARKS. [Alphabetical under each State.) CALIFORNIA. Acampo Alston Alta Altamont Antelope Applegate Armstrong Arno Auburn Banta Belmont Benali Beresford Blue Canyon... Boca Bowman Brighton Brightside Burlingame Calvada Caporn Castle Castro Cayley Cisco Clippergap Colfax Crystal Lake. . . Davis Dutch Flat East Auburn... Eder Eliot Elk Grove Ellis El Pinal Elvas Emigrant Gap. Fair Oaks Farwell Flint Florin Floriston Forest Lake French Camp.. Fulda Gait Gold Run Gorge Graham Hammer Hislop Holy Cross Iceland Irvington Jahant Jam Lake View Lander Lathrop Lawrence Llvermore Lodi Loomis Mayborg Mayfield McDonnell Menlo Park Mettler Midas Midway Millbrae Milpitas Mountain View Mystic Need Nestor Newcastle New England Mills. Niles Orel Palo Alto Pearson Penryn Pleasanton Polk Eleva- tion. Descrip- tion. Paget. 46,47 47 47 46,47 46,47 47 47 47 47 46,47 46 46,47 46,47 46,47 47 47 46,47 46,47 46,47 46,47 47 47 47 46 46,47 46,47 46,47 47 47 47 46 46,47 47 46,47 47 46,47 46 46,47 47 46,47 47 46,47 47 47 46,47 47 46,47 46,47 47 47 46 47 46 46 46,47 46 47 47 46,47 46,47 46 46,47 46,47 47 47 47 46 46,47 46,47 47 47 46,47 46,47 46,47 46,47 46 46,47 47 46,47 47 46,47 46,47 46,47 46,47 47 46,47 47 Pages. 57,58 ;>s n Place. .57 California— continued. Prosser Creek... Racimo Radum Redwood City. . RemiUard Rocklin Roseville San Bruno San Carlos San Francisco . . San Jose San Mateo Santa Clara Sibeck Smart Soda Springs... Spruce Stockton Summit Sunnyvale Sunof. Tamarack Towle Tracy Troy Truckee Tunnell TJlmar Verona Walerga Warmsprings. . Wayne Wickes Winsted Wirt Yuba Pass Zeta NF.VADA. Akbar Alazon Anthony Argenta Argo Avenel Banvard Battle Mountain . Benin Beowawe Carta Cedar Clark Cluro Cobre Coin Comus Cosgrave... Deeth Derby .' Desert Ditho Doden Eglon Elburz Elko Falais Farrel Fenelon Fernley Gerald Gilpin Golconda Granite Point Hated Halleck Harney Hazen Herrin Holborn Humboldt Huxley Icarus Imlay. Iron Point Kaw Kodak Eleva- tion. Pages. 46 4," 46,47 46 47 46,47 46,47 46,47 46,47 46 46,47 46,47 46,47 47 47 47 46,47 46,47 46,47 46,47 47 47 46,47 46,47 47 46,47 46,47 47 46,47 47 46,47 46 47 47 46,47 47 47 45 45, 47 45 45,47 46,47 45,47 45 45,47 45 45,47 45,47 45,47 46,47 45,47 45,47 45,47 45,47 45,47 45,47 46,47 45,46,47 46,47 45 45 45,47 45,47 46,47 45,47 45 46,47 45,47 46 45,47 45,47 46,47 45,47 45,47 46,47 45,47 45 45,47 45,47 45,47 45,47 45,47 45,47 45 Descrip- tion. Pages. 66 57 57 60 60 60 59,60 60 60 59 57 50 51 51 53 55 52 50 53 53 52,53 52 51 55 52 50 52 53 53 51 55 54 55 53 53 51 52 55 53 51 55 52 55 53 54 55 51 52 55 53 51 54 54 51 54 53 51 54 Place. Nevada— continued. Ladoga Lamar Lawton Loray Lovelocks Luva Mannol Massie Mill City Miriam Mogul Moleen Montello Moor Mosel Mote Nardi Natchez Noble Ocala Omar Oreana , Osino Palisade Parran Patna Perth Pequop Piute Preble Rasid Reno Rose Creek Rosny Rye Patch Ryndon Sparks Starr Stonehouse. . . Tecoma Thisbe Tonka Toulon Toy Tulasco Tule Tyrol Ullin Upsal Valery Valley Pass.. Valmy Verdi Vista Vivian Wells Winnemucca. Woolsey Wright Zola UTAH. Balfour Blue Creek Bovine Brigham Corinne Dewey Gartney Hansen Honey ville Kelton Kolmar Lake Lucin i Monument Ombey Peplin Promontory Romola Rozel Surbon Terrace Umbria Junction . Eleva- tion. Descrip- tion. Pages. 45 45 46 45,47 45 46 46 46,47 45,47 45 47 45,47 45 45,47 45,47 45 45,47 45,47 45 47 45,47 45,47 45,47 45,47 45,47 46 45 45.47 45 45 47 46,47 45 45 45,47 45,47 46,47 47 45,47 45,47 46,47 45,47 45,47 45,47 45,47 45,47 45,47 45,47 46,47 45 45,47 45,47 46 46,47 45,47 45,47 45,47 45,47 45,47 45 45 46 45 45,47 45,47 45 45 45 45 45,47 45 45 45,47 45 45,47 45,47 45,47 45,47 45 45 45 45 67 Pages. 53 53 56 50 54 55 56 55 54 54 52 50 51 53 53 51 51 50 "50 54 52 52 54 55 54 51 53 53 "56 53 53 54 51,52 56 "53 50 55 52 64 54 51 53 62 50 54,55 54 50 53 56 55,56 52 51 53 54 50 54 48 49 50 48 48 48 50 48,49 48 49 49 49 50 49 49 49 49 49 49 49 49 50 o