SIR WILLIAM EDMOND LOGAlJr. 361 



The previous attempts to establish a parallelism between the geoloo-i- 

 cal succession in eastern New York and western New England had 

 led most American geologists to suppose that the crystalline schists of 

 the latter region were the stratigraphical equivalents of the lower 

 members of the New York Paleozoic series in an altered condition ; 

 though there were not wanting those who, with Emmons, regarded 

 these crystalline strata as a part of the primary or so-called Azoic series. 

 Logan, who began, as was his custom, to work out the stratigraphy of 

 these rocks in minute detail, accepted the views of the majority on 

 this disputed question, and endeavored to establish a parallelism be- 

 tween the subdivisions of these crystalline strata of the Green Moun- 

 tains and their prolongation into Canada, and the uncrystalline fossili- 

 ferous strata which are found evei'ywhere along their north-western 

 base from the valley of Lake Champlain. These, the so-called Upper 

 Taconic of Emmons, he at first looked upon as newer than the Tren- 

 ton limestone, but, yielding to the evidence of organic remains, assigned 

 them at length to their true position immediately below the horizon of 

 this limestone, and named them the Quebec group. That these un- 

 crystalline strata were really newer rocks than the adjacent crystal- 

 lines (of which they include fragments), Logan was unwilling to admit, 

 and spent many years in an unsuccessful attempt to establish a corre- 

 spondence between the two series. That these latter rocks, called by 

 him the " altered Quebec group," belong to the same Huronian series 

 which he was the first to distinguish farther to the westward as of pre- 

 paleozoic age, will now be questioned by none who have compared the 

 two regions. 



The record of Logan's later life is little else than that of his patient 

 and unwearying devotion to the work of the geological survey of Canada, 

 of which he remained the director for twenty -five years. In 1863, he 

 prepared and published, with the aid of Professor James Hall, a 

 geological map of northeastern America, including the region north to 

 James's Bay, south to Virginia, and west to Nebraska. This map, on 

 a scale of twenty-five miles to the inch, remains the most complete 

 attempt to delineate the geology of the region. His other published 

 works are confined to the reports of the geological survey, and a few 

 papers to scientific -societies on kindred subjects. He had little aptitude 

 for literary labor, and found the work of composition difficult. He 

 rendered good service to science and to his native country at the inter- 

 national exhibitions of 1851 and 1855, being a juror at the first, and a 

 commissioner at the second. On the latter occasion he was knighted 

 by the Queen, and by the Emperor Napoleon made a chevalier of the 



