6 THE ROYAL SOCIETY OF CANADA 



three decades 1840-1870 may well be regarded as the "Loganian 

 Period" of Canadian geology. 



Logan, as he himself says, was a stratigraphie geologist, but he 

 was also a wise man, and knowing the source of funds for the prosecu- 

 tion of the work, he never lost sight of the economic aspect of the 

 subject. He entered on his duties under the influence of his distin- 

 guished sponsors at the time the Cambrian-Silurian controversy was 

 beginning, a controversy which became more complicated by the 

 introduction of the Taconic Question and which had scarcely died 

 away when his term of office expired. Murchison's Siliiria appeared 

 in 1854 and was followed by Sedgwick's rejoinder in 1855. After 

 this date "Cambrian" was ofificially ruled out, but Sedgwick continued 

 to support his convictions until his death in 1873. 



Logan seems to have adopted Murchison's view, for the word 

 "Cambrian" does not appear in his reports and "Taconic" is likewise 

 conspicuous by its absence. With Hall and Dana he remained 

 obstinate as to the identity of the Taconic rocks Vv'ith the Champlain 

 or lowest division of the New York system. 



De Verneuil in 1846 made the first serious attempt to correlate 

 the rocks of America with those of Europe and established for America 

 the boundaries of the Silurian and Devonian systems. Logan con- 

 tinued to use the New York nomenclature until 1852 when he intro- 

 duced the European terms. The report of 1863, which does not differ 

 from Logan's latest reports, gives the following as the major divisions 

 of geological time as revealed in Eastern Canada — ^Car boni ferons, 

 Devonian, Upper Silurian, Middle Silurian, Lower Silurian, iVzoic. 



Logan was the father of Canadian geology. Tireless, self-sacri- 

 ficing, enthusiastic, he gathered around himself a small body of loj^al 

 and efficient assistants; forceful, prudent, yet pliable, he was able to 

 guide the infant Survey through many shoals of governmental non- 

 support. His first assistant was Alexander Murray, a trained geo- 

 logist appointed in 1842. The following year he worked in co-opera- 

 tion with Dr. William Dawson, then only 23 years of age, but who 

 afterwards played so important a part in Canadian geology. Logan's 

 other field assistants were not numerous; James Richardson, a farmer, 

 was appointed in 1856, Robert Bell a civil engineer in 1857, and later 

 G. Vennor, Charles Robb, and Edward Hartley. 



It is not the purpose of the present paper to speak of the work 

 accomplished by Logan and his assistants in the field of stratigraphie 

 geology. That work is monumental and familiar to you all. It will 

 suffice to state that practically all the stratified rocks from Mam- 



