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Un dee symboiea suivan^s apparaitra sur la demiire image de cheque microfiche, selon le caa: le symbole —«*• signifie "A SUIVRE ", le symboie V signifie "FIN". IVIapa. piataa. charts, etc.. may be filnrad at different reduction ratioa. Thoae too large to be entirely included in one axposure are filmed beginning in the upper left hand comer, left to right and top to bottom, as many framea aa required. The following diagrama illuatrate the method: Lea cartea. planches, tableeux. etc., pauvent atra filmte i dee taux de rMuction diffirents. Lorsque le document eat trop grand pour itra reproduit an un saul ctichi. il eat film* A psrtir dw I'angle supMeur gauche, de gauche ^ droite. et de haut en baa. 1% prenant le nombre d'images n^ceaaaira. Lea diagram mas suivants illuatrent la m^thoda. 1 2 3 1 2 3 4 5 6 Division of Palaeontolo(ry SHHfliPates Tte hnz and Potlioles at Rockwood, Ont > »•» < By Prof. J. Hoyes Panton, M. A., F. G S. The followinj; is the fall test of the Dftper read by Prof. Panton on the above ■nbjeot at the meef'ng of the Gaelph Boientiflo Sooiety on t. 13th iiiat : - Some time ago while on a trip to Rook- wood, with ataden'B of GeoloRy from the Agrionltnral Oollepe. for the purpose of ■howioK them some exarai)le8 of how water aota upon limestone I was forcibly impressbd by a moat interesting aeries of Potholes found in that distriot, not far from where the somewhat well known oavea are aeen. S3 impreaaive were these phenomena, that tor three oonaeoutive holidays, the Students made their way to Rookwooa.and on two of the ooc^aiona.were accompanied by myself. A thorough examination of the locality was made, and dat* ooUpoted, which I purpose plaoini! before vou this evening, and which should be interestina to a Society that has bi-en established for the parpoae of developing the history of our neighborhood whether it be written upon the rocka or pmes of a more perishable character. In treatint! the subject, the following divisions are naturally presented : — 1. The location of the Caves and Potholea ; 2. AdeBoriptiDHof them; 3. An explana-ion of thuir formation ; 4. Theories concerning the otiein of the phenomena, that caused their formation. 1 — LOCATION. Rookwnod is a sm'ill village on the line of the Grand Trunk Railway, eituntc-d about 8 miles eafl-: of Guolph, and 4 J west of Toronto. Leaving the station and pro- ceeding in the direotior; nt the village, yon verv iOO" obiervn that you iiro in a place Wdil uamdd— Riokwood, from tha amiunt of rock lu the vif.iiiit>. Ai^'ng ilv river, whioh pisses ihrongh the villayo are Btriking expnaur^a of rock, at some places esoarpmoiits 50 to 70 feet liig>i made up largely of masaivo Is.yers of Maguesian limestone, bnlon^iing to the Niagara forma- tion of the Silurian syBlem. Foesila are not numerous, (kinoii stems are by far the moat common ; a few sheila ocour.and some fragmenta of coral, eapeoia'.'.y the genns Faoosites. The fragmentary re- maina of the Orihocaraa are seen at some places, bat the fossils are neither common enough, or so well defined aa to work up the zeal of young geologiata. However, »fter you have passed over the bridge that laaila to aorae milla and the large q uarriea Mid lime kilns near by, you reach looahtiea well suited to arouse enthneiaam in the mind of young students in science. The presence of three large lime kilns "^pmon. etrate, that this atone produces e^xjellent lime, exceeding a' >ng and well adapted for building purposes. As yon pass westward, along by the quarries, yon obtain a fine view of the escarpment on both aidea of the so called river land grand monuments of denuda- tion are before you. In the distance about half a mile is the "Pinnacle"; a large isolated piece of high rock, standing midway in the upper patt of the mill pond. But at your side on the south side of the road along whioh you are travel- ling, your attention is arrested by a great hole at the baae of the rocka. Thia is the entrance to a cave, whioh on examination proves to be of more than passing interest. In a line almoat southeast of this *nd only a short distance awav, but on the top of the bluff, you reach a pothole which rivals some that for yeara have b»ea a groat source of attraction to tourists stopping at Lucerne, Switzerland. Woodcuts of these are snatterei in every direction, and no one can say that he has made a proper visit to Lucerne unleos he has visited the "Glacier Garden" and obaerved the aeven potholeti, that are ailent mouumenta of glacial phenomena long since ended— Yet here at Rockwood we can get a series of potholea larger in some reepeota and more unique than thoae at which so many thousands g»zs in wonder each paesing year. ihe formation and origin of these we will consider Ruhaeqnently. 2— DESCRIPTION OF THE CAVES. The entrance to the main cave is 1.5fe6t high and obatructftd by great maaaea of rock, which have fallen from the roof. From thf top of thfj oave to the anmmit of th-t overhanging rook ia 40 feet o( solid dolomitin lime atone. Prnofieding into the cavern yon observe that the roof ia very irregular, linking at timea to 5 feet, theu riaiug to 7 and sinking again. At the mouth it la 29 feet wide and narrowa to a width of 16J at a diatance of 36 feet from the entrance. Here it ia only 5 feet high hut on paaaing thia point yoa reach anoth- er chamber, whioh widena and haa at the left aide a small chamber eight by aix feet, but soon narrowing and dipping down till the cave seema to terminate at a point 30 feet farther than the narrow part and 86 feet from the entrance. This is as muoh of the cave as most visitors see, but beinjj accompanied by studenta of more than or- dinary pluck, endurance and zeal I was eucoessful in securing data whioh -ill en- able yon to form •ome interesting oon- olosioDS about tbia oomparatively unknown ■pot. LigUt enda bere. A lantern was ob- tained and entering one by one « pLtaaage ■oaroely lar^e enontth for a houiaii being to f;otbrookh, for 8 feet, MeeBre. Craig, Rayoor, Patterson, Sharman, Ztvitz, Bisbop and Fee, wormed tbemeelvea through into another aave, ahroaded in Egyptian darkoeas and Kloora. Tbia ex- tenda 10 feet to the lefl and 15 to the ri^bt i.e., had a diameter one way of 25 feot and 13^ the other. To the left and right tbev found a pillar not far from where they entered , these supports seem to have been formed by the rest of ihe rook wbiob once made up the solid rook bemg carried away. At th? ex- tremity on the right hand side the floor was very muddy, and two cm-ill caves ex- tending still farther, one near the passage by which thsy entered, the other at the opposite Bide ; the farmer three feet by four, the latter three feuc at the opening and tapering to a point and dipping down- ward. Prowling about in this .;loomv chamber, not high eooagh to proceed com- fortably, for It was only about live feet in the centre, they shiw etalautit'-B nnd stalag- mites, some of tbem a foot in length and four to five inches indiamaterat tbe thick CBt place. The flour of this chamber albo dips slightly down. Directly aorotis they came upon another pillar-like structure, with a paseage on each side, opening into another apartment, where the roof waa not over three to four feet hibh.und gradu- ally narrowed so as tn render farther pro- gress difiionlt. This extended ten fpet across and about tbe same in width. Ou the oppoaiiti side from tbe entrat'-p, there is ar opeuiog leading, still fan her, bat the paseage graduiilly narrows until ftrther advanoe- ment is strpped. Through this opening Mr. Riynor panged, an' thr>-Hded his way 13 feet, and reached a point llOJ feet from the entfnoe to the main cavt 1 he fl jor of the laet chamber inuiiues B'i; it waH h illuw hi neath.and from the faijt that the prolougttion of the former chamber, near where thiM waa en- tered liipa downward, it id HUppot>ed a p^S' sage frim it oontiLUes i^tid likely paesea onder this lawt fl rar. All thnu^h these darkened caverns a good deal of rnul was enooutitereJ. Water tri'klint! down the side:! and dropping from tiH roof added to the gloom of these darkened rec saea, where daylight hai nevrr vet penetrated, and whose walla dimly liiihttd by the flickering light (^f the lantern, presented a BOmewh'iti weird, unattractive appearance. When the explorers emerMed from these inner reoeasee of darkne>-8, their clothes preeeiitei quite a ch-ing d appearance and indicated that mnnh of their travelling muBt have been done in a somewhat menial position, and that they hud been much associated with mud and wa'er within. A little to the'left ot the • ntranoe to the main cave there is an opening, which leads to another series of obambera, extending to a distanoe of 69 feet. At a point in tbe vicinity of the flrst narrow place in the main cave there is a narrow passage leading into this series, in which the apartments are not so oompli. oated, and being dry are much more easily examined. Tbe first ia some 25 feet long and 12 wide, narrowing to a passage into the second, 10 feet aoroaa, and opening into the main cave. The general direction of the main cave ia E. by 8. E. to the narrow portion, then S. E. by 8.; thia course ia maintained till the end ia reached. The roof through the whole seriea ia ex- ceedingly irregular, and tbe floor in many parts covered with fragments ot the lock, which have fallen from tbe roof. 8talao- titoa and atalagmites are found only in the inner chambers, and the latter seeni more common than the former. Some mayiiave formed in the outer, but have likely been carried away by visitors. The diagrams before you will give a clear idea of tbe arrangement of tbeaeBub. terranean passagea and chambera, and their relative position to each other. The whole aeriea may be termed one cave, con- sisting of six well defined caverns, and as a sort of expansion on tbe sides of these four small onea. POTHOLSS. Leaving the oaves :.,nd olamberinp up the sides of one of the quarries near by, you reach the summit of an apparent peninsula of solid rock, along each side of which a stream flows at tbe present time, bordered by precipitous clifis 50 to 75 feet high. The general direction ot this rooky ridge ia north a-cd south. The streams are united about a mile farther to the north, and after passing along the sides of this marked rork eleva- tion, they join in the vicinity ot Farribh'a mill, and thus forming in reality an island, which terminates at its southern extremity in a limestone oliff. About 5C0 yards from the caves, and near the end of tbe bluff, you suddenly come upon an immense boie in tbe solid rook ; it has an oval form, its longer diameter being 20 feet and the shorter 15 ; one side is 10 feet higher than tbe other ; it' lies in a slight depressiin in the rock, which terminates at the side of tbe hole, with an abrupt fall of 22 feet. At the bot- tom of the hole you perceive an opening 4 feet hith and 2 feet wide, but of an irregu- lar outliue, thia opens into a aort of valley, buli it must be remembered thia is 40 — 50 feet above tbe level where the streama are fl )wing, Thia valley has rock on bjth sideo and forma a baantifal glen, at the present time a popular haunt for boys delighting to revel in the pastimea ot youth. Following in a southwest direction for BomeGOyarda the rock risea, and a little farther on ends abruptly with a fill of about 50 feet into the valley, through which a very insignificant stream at pre* sent passes. On the opposite sidi? of the valley about 100 yards wide at this place, the esoarpment is fully 75 yards high. About the middle of this valley a slight elevation of Bolid rook some 15 feet h'lKb oooars. It ooonpies a peoatiar poaiiioa and form, ap- pearing ae if BtroDg onrrenta bad worn away rook material.and left this irregular oatlier, as a raonaicent of oonditiona no longer Been iu tbia pUoe, where a mere oreek meandera throngb a well defined ravine. In tbis isolated area of rook on examin- ation you find a a.oat intereatiog and in- Btrojtive aeriea of Potholeci, 6 in namber, to some extent in a line with the lurge one already referred to, aa located about ' 150 yards to the N. E. A more unique aeries oonld aoaraely be imagined. Galling that already d^-aoribed aa No. 1, then here we have : — No. 2, 6 feet by 6 and 7 fnet deep ; No 3, 1 foot by by 1 and 3 f«et deep ; No 4, 6 feet by 6 and 12 feet deep ; No. 5 8 feut by 4} and 8 feet deep ; No. 6, 6 feet by 6 an < 10 feet deeo j No. 7, 12 feet by 6 and 3 feet deep ; No 1, 20 feet by 15 and 30^ feet deep, from the hitibest aide to the bottom and 21 from the loweat. Tbeee Lolea in the rock have nanally a greater ditimeter about half way down. The following raeaanrementB of No. 1 will show thia :— Four feet from the bottom, 21} by 18 feet ; midway, 23 5-6 tba by 19^ feet ; six feet from the top, 25 by lOj^ feet. Generally speaking the outline of a vercioil n<«otton is oval. Holes 2 and 6 are on the edge of the rook, an.i oonstqaently are somewhat im- perfect ; from 5, which oomt-s near the edge, there is a small hole, which opens into the valley ; tbia enabled us to empty it and learn the nature of its oontenta. At first we were deairoua to investigate the oontenta of No. 1, and with that vie'v dug for the flrdt day, and returned to continue the work. Mnub soil, fragmeota of rock, etc., were dug up and wheeled away, but we found no trace of rounded etonea. After several hjura of hard work, it was resolved to proceed to the series in the valley and explorn some there. The facilitio!< far working »t the large hole are good, iniiHtnaoh aa the material OouM be lo'ided into the wheelbarrow at the bottom and wheeled aw»y a short dis- tance and emptied into the ravine a few feet below. It is hoped on some future oooiiaion mombrrs of the Society will follow up the work undertiken here, and finally olea.n out the bottom of thia atrange place. We proseeded to No 5 and entered npon the work of cleaniui> it out ; only a few spadefuls of earth were t^ken out when some stones were found, whose rounHed shape had a wonderful inspiring effeoli npon the workers. They wern very round, and were ct an entirely d'ffdrenii compoaiiion from the solid rook iu which the hole had been ex- cavated. After some two hours digging the bottom waa reached and a fine collection, about two p-iilfula, of rounded atones was obtained, varying from 6 inchea io diameter to half an inch. Many of the email stones were at round as marbles. These sixteen before yoa represent some typioal forma, and will enable yon to form an idea of the interesting nature of these stones, whose very appearance suggest qaestiona aa to how they came to be so ronod, and bow they g^t where they were found ? We bad hoped to have found similar in the large Pothole, whether euoh will be, remaina to be seen. It might poB^ibly be, that tbey have rolled ont throniih the passage at the bottom of the hole and mnat besought elsewhere. No. 3 being small waa emptied and some of the flaeat speoimena of small rounded stones were got from it. Noa. 2, 4, 6, 7 have not been eximined,and it ia probable that an examination of them will meet with even more gratifying reaults than those emptied. Having had thu pleaanre of seeit^g the Potholes at Lucerne in Bwitz^rland, "j does aeem to me that at Bookwood there ia as interesting a series. Along the river near the quarries 18 mure or less defined holea appear, and in this locality under conaideration 12 in all are found, and of these the seven more par- ticularly described are exjeediogly unique in form, position aud structure, and were they near a large city would be a source of great attraction to visitors in- terested in the worka of nature. 3 — fjrmation of thk oavks and potholbb. In all distriota, where limestone exists, it is not oncommon to find caves, especially if water U near. Water con- taining carbonic acid (a gns generated in the deoompoaition of vegetable material and largely present in the atmosphere, from them the respiration of animals ; for the air expelled from their luogs ia charged with it,) has a powerful di»integ- raticg effect upon the carbonates of lime and maiinesia, forming from them bi-oar- bonates, which are soluble in water and as such are carried away ; consequently it is only a matter of time before limestone (a carbonate of iiorje) when acted npon by water containing this gas ia completely dissolved. A m-^re dripping in a crevice will in time effect qai'.e a change and form considerable of a cavity. If the quantity of water ia considerable, the change is accomplished in a shorter ppriod Very f'iroible examples of this disinte(/ratint> effect of water on limostoae were observed by mo in DTbyshire thia anmmer. There are ravines there which are supposed to hive been formed out of the SLlid rock in ages long receded into the past. These ravinea were once overoapped by liranstone, the cave or ptssaue itself dis- solved and ctrried away by water, finally the top fell in and the debris carr ed bp-v- ward, until now all that marks the great oaves are the walls, which form esiarp- ments along the ravine, through which a rivuUt passes at the rreS'^nt time. Near by a great cavern (Poole's) explains the prooesi; the entrance ia narrow and low ye^, 12 feet in, and you reach a much wider passage, and as yen proceed immense apartments are entered, ao that you pa'js along a tortnona pathway for several hundred yards. Borne of the apart* manta are 30 by 30 feat high mad 40 wida. Mo raanioK dtteain ie aevn to indicate the oaaae. bat the w*ter trioklinK down the ■idea uzplaica thia ^reat diaintagration of (ifae limestone ; so here, oominK nearer home, at Rookwood, yon find oavei not ■O extensive, bat aa ohkraoteriatic of the Mtion of wacera aa those I have been re- ferring to. The preaenoe of mad in the back part of the iaoer cavttruti at BookwooJ seuma to indicate a ooaneotion between them And the sarfaoe throagb fiaaareb in the' rook. Thia mud beara a cloae rcaemblanoe to the aoil whioh oovera the rook above, and baa likely been broa^ht down by rain throneb theae orevioea. Thia rain charged with oarbonio aoid in time ooald easily diasolve oat the rook and leave the oaverna M we find them no«. Frost would assiit in breaking off fr«gmenti3. aa we find them now Boattered along the floor o( the oave, ^hile the aidea preeent a very irregular •ppearanoe. The prewnoe of atalaotitea on the roof and atalagmitea on the floor, also ahow mooh disEoIving of rook by water, for these atraotnrea are merely the pieoipi- toted lime from the water, whioh haa car- ried it down. The w«ter on reaching the roof evaporatea, and the lime ia left, tbia ffoea on adding partiolea of lime, until a etraotnre is formed not unlike an ioiole in form, but oompoaed of oarbonale uf lime. Sometimes the drops fail upon the floor and form something of the same in form. The atalacti'^^ea areaometimea boUcw but the stala^^mites are folid ; this is owing to the one being formed on the roof and the other on the floor. In some oasea, those from the roof fall and beoome ic- bedded in the material on the floor. At Bockwood the stalagmites are more oom mon than the sOaUctites, seeming to iudi oate that the water ooucainiog lime in aolution falls before evttporttticn takes plaoe, and oonseqnently a tentlenoy for an aooumnlation of lime on the floor. POTHOLES. The Potholes, too, aie no doubt tho re- anlt of the antion of tbn water, but in this case the aotion ia more meohanical than ohemioal. Water moat have pa^ieed over aa a atrccg current, tho place, where the potholes aro now but in their flfat atai^es only a slii^ht depret>aion w-xa in the rock. In theae some Hard atonea collected and according to the atrentith of th? current, the raovfiment o( the etoneiJ would depend ; the motion produced would aeon lea(T to a wearing away of the rook. Holes would form a,nd deepen, tia time roiled on, nntil a cavity would b^ produced not unlike a pot in outline. In uU the holes examined, the diameter midway down was greater than at any other point. The atonea grinding thia ont bein>< harder than the rook, for you uaaallv find they are pretty maoh the aame aa our bonldera in the field withatand the wear and tear well, but in the ooarae of time they beoome ronnded and finally auooeeded in making a pothole, whioh will vary in size accord- ing to the length of time the grinding haa oontiuaed, the foroe of the oarrent and tiie hardnesa of the rock acted upon. To-day we aee no water near soma of theae holes, but we find that when the loone aoil in the bottom of the holes ia dug up ■ii oontaina innumerable rounded stones of all sizea from a marble to that of a common ball, have already aaid the maohanical aotion of stonea and water upon the lime- atone, in whioh wh find theae holes, have affected the condition of thint^a we at pre- aent observe. Thpre are two waya in which theau currents of water may have acted. 4 -THEORIES or FHENOMENA. 1. That of a great river, which filled the whole space betwe^Ji) the highest banks at Kockwood, a atreaabearing a'ong a great body of water, with a strong out rent A.a time rolled on it gradually leaaened in volume and formed two atreams, running along the valleya in which, we find the streama of to day, but muoh larger than they. At some period in this great river'a exiatenoe it flowed across the depression, where yon see the largest Pothole, and flowing over the precipice pursued its coarse along the line in which we find the other Potholes. 2. The water may have been a oarrent under a glacier as we m^e in some cased at the present tim^ in Alpine diatricta. A orevaaae (crack) may occur milea from the end of a glacier, into thia water formed on the surface, aa it pushes its way into warmer loaaliti>'a, falls and finally makes its way ont nnder tho threat stream of ice. Such an under current setting! into a de- preaaion in the rook, aided by atonea from the glacier would bi aaroto produid Pot- holes. This U the ori»^in of thospi at Lao- erne. In Buoh casea yon are likely to fiad, that th(4 stones derived from the glacier that did the work are lar^^e, and that the surface of the rnnk ia much abraded illas- trating glacinl atrial vt ry impressively. At Rookivood Potholes we so far have not been beon ablo to discover glacial markings, and among the ronnded stones none exceeding six inches in diameter.and thus are inclinei to think these holes have been worked ont by the water of a river rather than that found beneath a glacier. However aa further information iaaecared we may be led to modify the conolusiona presented to-night,