

WILLIAMS] LOGAN. 235 



nized by Logan in Canada West. Acknowledgments were made of the 

 services of James Hall in tracing out in 185G with Mr. Murray the 

 boundary of the Upper Devonian rocks in a part of the western peninsula. 



In the report 1 Logan recognized the Oriskany, Corniferous, Hamilton, 

 Portage, and Chemung formations of the New York system, lleference 

 is also made to the correlation of the higher Carboniferous rocks in 

 Michigan and their relation to these Devonian rocks. 



The Oriskany sandstone is reported from Waterloo, on the Niagara 

 River, and extending westward at Oneida and North Cayuga, but is 

 not recognized beyond the township of Windham. It is from 6 inches 

 to 25 feet thick, but is frequently missing between the Waterlime and 

 Corniferous formations. 



The Corniferous formation is estimated at ICO feet. It presents vari- 

 ous characters, cherty limestone, calcareous shales, light or dark, bi- 

 tuminous and hydraulic beds being reported at different localities. 



A series of shales and shaly limestones is reported as "Hamilton 

 formation." At Bosanquet the following section is seen : 



Feet 



Gray Encrinal limestone '. 2 



Soft shales 80 



Solid Encrinal limestone 2 



Gray calcareous shales (Spirifer mucronatus) 4 



Gray calcareous beds 25 



At Austin Mill, 50 or 60 feet below the Encrinal limestone, occurs a 

 solid arenaceous limestone, 7 inches thick, under which are black shales 

 doubtfully referred to the Marcellus shales. The soft marly beds, with 

 thin beds of limestone intercalated, containing Spirifer mucronatus, are 

 also referred to the Hamilton formation. The thickness of the forma- 

 tion is estimated at 300 feet. In several localities (Cape Ipperwash, 

 Kettlepoint, Bosanquet) a black, fissile, bituminous shale, 12 to 14 feet 

 thick, weathering gray and holding spheroidal concretions, is correlated 

 with the Genesee shale. The author expresses the opinion that the 

 363 feet of rocks in Michigan called "Chemung" and "Portage" by 

 Winchell lie above the "Black shale." 



In a paper 2 describing his studies of the Coal Measures on the coast 

 of Cape Breton, J. P. Lesley 3 called in question the reported thickness 

 of the Coal Measures. He said : " The geologists, Sir William Logan, 

 Sir Charles Lyell, Professor Dawson 4 and other geologists who have 

 described the Coal Measures of Nova Scotia and New Brunswick agree 

 in assigning to them an almost incredible thickness." 



1 Geological Survey of Canada: Report of progress from its commencement to 1863; illustrated by 

 498 wood cuts in the text. Montreal, 1863, 8vo., xxvii and 983 pp., by W. E. Logan. 



" This discussion is referred to at the opening of the present chapter. The original papers were 

 published in the American Philosophical Society Proceedings. 



3 Lesley, J. P.: Section of Coal Measures on the Cape Breton coast. Am. Phil. Soc. Proc, vol. 9, 

 1863, pp. 93-109, 167-170 ; Am. Jour. Sci., 2d ser., vol. 36, pp. 179-196 (Revised). 



4 Dawson, J. W. : Note on Lesley's paper on the Coal Measures of Cape Breton. Am. Phil. Soc. 

 Proc, vol. 9, 1863, pp. 163-167, 208, 209. 



