384 REPORT OF NATIONAL MUSEUM, 1904. 



He further wrote: 



One of the most interesting changes in the products on going westward is the great 

 increase of carhonate of lime, and the diminution of shaly and sandy matter, indi- 

 cating a deeper ocean or greater distance from land. The source of the calcareous 

 deposits is thus shown to have been in that direction, or in the southwest, while the 

 sands and clays had their origin in the east, southeast, and northeast, producing a 

 turbid condition in the waters of these parts during long intervals, and the formation 

 of chemical deposits. In New York we are evidently upon the margin of this primeval 

 ocean, as indicated in the character of the deposits as well as organic remains; the 

 southwest unfolds to us that portion where greater depth and more quiet condition 

 prevailed. 



This is apparently the first clear enunciation by an American geolo- 

 gist of what are now generally recognized as well established geologi- 

 cal principles. 



It was but natural that Hall, while geologist of the fourth district of 

 New York, should write concerning Niagara and its gorges. The 

 views of Bakewell, Rogers, and Hayes have been already noted in 

 these pages. Hall in his State report (1841), but more 

 Concerning Niagara, in detail in the Boston Journal of Natural History for 

 1842, covered the ground in a manner much more 

 thorough and scientific than an}' of his predecessors. 



Hall announced at the outset his disagreement with Doctor Dau- 

 beny," who considered that the terrace or escarpment at Lewiston was 

 produced by a fault, as he found no evidence whatever of even the 

 smallest disturbance. 



He noted the abrupt change in the direction of the stream at the 

 Whirlpool, and also the gravel-filled channel extending from this point 

 to St. Davids, but, singularly enough, failed to realize that this may 

 have been the one-time channel of the Niagara. He felt, rather, 

 that this ravine was excavated by the power of the waves of the sea, 

 aided probably by a stream which may have been of very insignificant 

 proportions. 



The fact was, however, recognized that the river was at that time 

 carving out its own channel, and the existing gorge from the falls to 

 Lewiston was due to the same cause. 



In 1841, after several years of agitation, there was established a 



geological survey of Canada, of which W. E. Logan was put in charge 



in the spring of 1842, the sum of £1,500 being appropriated for the 



purpose of carrying out the work. During the season 



Establishment of a , , . 



Geological Survey of 1842 Logan spent several weeks in examining por- 



of Canada, 1842. . „ , , ,. -, , ,, ,., ,-, , -.r -r, 



tions of the coal fields of Nova Scotia and New Bruns- 

 wick, and made his famous section of the Coal Measures at the South 

 Joggins, which gave the details of nearly the whole thickness of the 

 coal formation, some 14,500 feet, including 76 beds of coal and 90 

 distinct Stigmaria under-clays. Logan remained at the head of this 



« Daubeny was professor at Oxford, England. 



