252 



KEPORT OF THE SELECT COMMITTEE ON THE GEOLOGICAL SURVEY OF CANADA. [1855- 



greatly deteriorating the Talne of his property. The surrounding 

 country was clay overlying porous chalk. On examining into tlie 

 matter, I found that an extended system of drainage, by means of the 

 so-called *' dumb weU3,"had come into operation in the district during 

 the preceding three or four years, and had thus gradually affected the 

 water power of the stream. These dumb wells are pits dug through 

 the clay into the absorbent chalk, and afterwards filled up with rounded 

 stones or other matters admitting the free passage of water. Drains 

 being led into these, the greater part of the rain-fall is carried into 

 them, and so down into the underlying porous rock. Wlienevcr there- 

 fore a Geological investic/ation of a district points out the existence of per- 

 meable beds, lying at an accessible depth beneath stiff clay lands, and good 

 surface drainage is not readily obtainable, recourse may he had to the me- 

 thod just described. 



We cannot consider these " instances of scientific results ac- 

 quiring practical importance" vei-y flattering to our Geological 

 Survey, or likely to win for it a cheerful support and encour- 

 agement from the practical men of Canada. 



With reference, indeed, to the first illustration, it does not 

 seem to be very improbable that an hour's inspection of the water 

 marks on the banks and in the valley of the streamlet would 

 have furnished the information to be deduced from " a Geolo- 

 gical Survey of such a district before the erection of bridges ;" 

 such, we apprehend, is the modest plan which would have 

 been adopted in Canada ; and as to the existence of available 

 ' permeable beds,' the first well sunk in a district must lead to 

 their discovery. Hundreds of mill-streams in this country are 

 annually failing in their supply of water, and at the same time 

 freshets are becoming more sudden and destructive, yet 

 no one would venture to advocate the expediency of sustaining 

 a geological survey with a view to arrive at the explanation of 

 these frequent and easily interpreted occurrences. Mr. 

 Chapman, however, was asked to give instances from his " own 

 experience in such Surveys of the practical importance of re- 

 sults which at firet sight might appear to be exclusively of 

 scientific interest," and with commendable candour he limited 

 his instances to those which had come under his independent ob- 

 servation ; not that the illustrations advanced can be said to be 

 possessed of much scientific value to the geological world, how- 

 ever important they may have appeared to a Hertfordshire miller ; 

 yet, experience is always worth consulting, whether won in the 

 difiicult pursuit of truth at the bottom of " dumb wells," or 

 acquired by the patient study of the water shed of a refractoiy 

 streamlet. 



Ques. — " Have you had an opportunity of ascertaining the 

 progress that has been made in the Geological Survey of this 

 Province ; and what is your opinion of that progress ?" A71S. 

 ' ' I have devoted several days to a very careful examination of the 

 work already performed, and the materials collected under Mr. 

 Logan's direction, and I can only express my wonder that so 

 much should have been done ; considering more especially the 

 small means hitherto at Mr. Logan's disposal, the want of 

 Topographical Maps, and other difficulties incidental to a new 

 country." No one would suppose that a just appreciation of 

 the value of the results already obtained by the Survey, could 

 be derived from an inspection even during broad-day light of 

 the minerals collected, as. they may have been obtained from 

 localities commercially inaccessible ; but, when they " lie in a 

 gTeat measure, buried in packiqg-cases in the vaults and sheds 

 of the Survey Office,"* the difficulty is proportionately in- 

 creased. It is only by a study of the published reports of the 

 work already done, that correct impressions can be obtained of 

 the real value of the Survey. We confess, therefore, to some 

 degree of surprise at finding Mr. Chapman state in the conti- 



* See Eeport of Committee. 



nuation of his evidence, that " several of Mr. Logan's valuable 

 reports, moreover, are out of print, and 1 have been quite un- 

 able to obtain eopies of them." This explains at once the 

 error alluded to in the May number of this Journal respecting 

 the discovery of the tracks of a crustacean in the Potsdam 

 Sandstone, the inference being that Mr. C. was not familiar 

 with the contents of the Reports of which he had been unable 

 to procure copies. 



Mr. Chapman is asked by the Committee to state some 

 of the new Scientific Traths which have been derived from 

 the Survey, and he enumerated among others the following : — 

 " Another very interesting discovery is that of the crustacean 

 tracks on the Potsdam Sandstone. The celebrated discussion 

 to which this has given rise in England has attracted the 

 attention of scientific men all over Europe to the results of the 

 Survey." Had Mr. Chapman enjoyed the opportunity of 

 studying Mr. Logan's admirable Eeport for 1851 and '52 

 he would have known the name and designation of the real 

 discoverer ; or had Jie met with the fourth edition (1852) of 

 Sir Charles Lyell's Manual of Elementary Geology he would 

 have found the following circnmstantial notice of the " tracks," 

 with the date of the discovery, and thus avoided leading the 

 Committee into error on a subject familiar to every amateur 

 geologist in Canada : — 



" Tracks of a Lower Silurian Reptile -in Canada."- — In 

 the year 1847 Mr. Robert Abraham announced in the 3Ion- 

 treal Gazette, of which he was editor, that the track of a fresh 

 water tortoise had been observed on the surface of a stratum 

 of sandstone in a quarry opened on the banks of the St. Law- 

 rence at Beauharnois in Upper Canada. The inhabitants of 

 the parish being perfectly familiar with the track of the 

 amphibious mud-turtles or terrapins of their country, assured 

 Mr. Abraham that the fossil impressions closely resembled 

 those left by the recent species on sand or mud. Having satisfied 

 himself of the truth of their report, he was struck with the 

 novelty and geological interest of the phenomenon. Imagining 

 this rock to be the lowest member of the old red sandstone, he 

 was aware that no traces had as yet been found of a reptile in 

 strata of such high antiquity. He was soon informed by Mr. 

 Logan, at that time engaged in the Geological Survey of 

 Canada, that the white sandstone above Montreal was really 

 much older than the " Old Red" or Devonian. It had in fact 

 been ascertained many years before, by the State Surveyors of 

 New York (who called it the " Potsdam Sandstone"), to lie at 

 the base of the whole Silurian series." * * * Early in the 

 year 1851, Mr. Logan laid before the Geological Society of 

 London a slab of this sandstone from Beauharnois, containing 

 no less than twenty-eight foot prints of the fore and hind feet 

 of a quadruped, and six casts in plaster of Paris, exhibiting a 

 continuation of the same trail. * * * Numerous 

 other trails have since been observed (1850, '51), in various 

 localities in Canada, all in the same very ancient fossiliferous 

 rock ; and Mr. Logan, who has visited the spots, will shortly 

 publish a description of the phenomenon." We may here 

 remark that Professor Owen first inferred (1851) that the 

 tracks were those of a fresh water or estuary tortoise. Agassiz 

 supposed that they were crustacean, in which view Professor 

 Owen coincided in 1853. (See Journal of the Geological 

 Society August, 1853.) 



Mr. Chapman being requested to state to the Committee 

 some of the advantages derived from the Survey by the dis- 

 covei-y of materials of economic application, replied : — " With 

 regard to economic discoveries, I may state generally that the 

 survey has brought to light the existence of beds of workable 



