258 RECORD OF SCIENCE FOR 1887 AND 1888. 



It has been a constant surprise to American glacialists that parallel 

 phenomena were not recorded by the geologists of Europe ; and it was 

 a source of something more than surprise to European geologists that 

 the Americans should find so remarkable phenomena in one of two re- 

 gions of practically identical Pleistocene history, while none such were 

 found in the other. So one of the most interestiug events of the last 

 year to American and European glacialists is the discovery of several 

 well-developed terminal moraines in north Germany by the American 

 geologist Salisbury during a visit to that country,* These moraines 

 agree in all leading characteristics with those of this country ; and the 

 discovery will unquestionably open a new field of research, and a new 

 vista opening iuto the past history of the world in Europe, as the ear- 

 lier discovery did a decade past for this country. 



Among the results of the detailed work of American glacialists dur- 

 ing the last decade is the discovery that the great mer de glace of the 

 Pleistocene was not a homogeneous and uniform ice field moving in the 

 same direction in all its parts, but rather a series of great tongue-like 

 lobes extending in dilferent directions and to various lengths upon the 

 interior plains of North America j and some of the most interesting 

 lines of investigation of glacial phenomena pursued byChamberlin and 

 his contemporaries relate to the forms, positions, and inter-relatious of 

 these lobes, and to their connection with the system of terminal mo- 

 raines extending from Long Island to Montana, to the drift sheet bor- 

 dered by these moraines, and to the aqueoglacial deposits into which 

 both moraines and drift sheets merge. Thus, during the last decade, 

 glacial geology has passed far beyond that initial stage of segregation 

 in which o' jective phenomena are simply assembled and described to 

 form a basis of study, and well into that stage of differentiation which 

 accompanies a wider growth of knowledge. 



One of the students of the American ice-lobes was Lewis, and when 

 he visited Great Britain, two years ago, his practiced eye and trained 

 judgment at once perceived evidences of similar lobation of the ice sheet 

 which plowed over the British Isles during the Pleistocene. So in 

 another way the seed of American thought has borne fruit in Europe 

 and Eastern science has been stimulated by the introduction of West- 

 ern methods, and another tittle of the intellectual debt of the new con- 

 tinent to the old abated. 



r:6sume. 



Several important conceptions in geologic science have sprung iuto 

 being in America during the past two years ; many old conceptions 

 have been modified and extended ; and some conceptions hitherto di- 

 verse have been brought iuto harmony ; and so, in a third way, knowl- 



* Am. Jour. Sci. 1888, vol. xxxv, pp. 401-7. 



