258 ROCHESTER ACADEMY OF SCIENCE 



in biologic geology or paleontology ; and almost nothing in stratig- 

 raphy and petrology. 



His geologic interest in his home region was mainly in glacial 

 problems, especially the glacial lake Iroquois and the deformation 

 of the Ontario basin. He was the first geologist to appreciate the 

 complexity of the Pleistocene history of the valley. As early as 

 1885 he recognized the three controlling factors: (a) the damming 

 effect of the waning glacier and the glacial nature of the earlier 

 waters; (b) the succession of water levels due to opening of dif- 

 ferent outlets or places of escape for the impounded waters, by 

 the recession of the glacier front; and (c) the dislocation and cant- 

 ing of the water planes by the tilting uplift of the land. His 

 accurate conclusions regarding the complex history are embodied 

 in a number of short papers, and especially in a chapter in the 

 "Sixth Annual Report of the Commissioners of the State Reserva- 

 tion at Niagara for the year 1890." The title of this important 

 but little-known paper is "The History of Niagara." 



Dr. Gilbert's mind was of the reflective, philosophic type. He 

 sought for the explanation and relationship of phenomena. His 

 calm judgment and clear discrimination joined to a spirit of fair- 

 ness and with gentle manners caused him to be much sought as a 

 critic and helper. He was a sort of father-adviser to the members 

 of the Survey. Doubtless much of his thought has found expres- 

 sion in the writings of the younger men who revered and loved 

 him. The writer of this appreciation never heard him say a harsh 

 word of anyone. He was reserved in personal matters, but it is 

 known that the death of a young daughter affected and saddened 

 his life. His wife, who was Fannie L. Porter, died over twenty 

 years ago. Two sons are living. The eldest, Archibald Marvin 

 Gilbert, is a successful civil engineer, in reclamation and irriga- 

 tion work in the west ; and had charge of the construction of the 

 great Salmon River dam. 



Dr. Gilbert received many honors. The University of Rochester 

 gave him the master's degree in 1872, and the LL.D. degree in 

 1898. The latter degree was also conferred by the University of 

 Wisconsin in 1894, and by the University of Pennsylvania in 1897. 

 He gave special courses of lectures at Cornell, Columbia and Johns 

 Hopkins universities. He was the fourth president of the Geolog- 



