168 ALEXANDER AGASSIZ 



of his work. The goal for which he was constantly headed 

 is revealed in his own words : — 



" The field of work opened to naturalists by thalasso- 

 graphic 1 surveys is of the greatest importance. The 

 materials collected throw a flood of light on our know- 

 ledge of the conditions of animal life in deep water, and 

 promise the most important general conclusions on ter- 

 restrial physics and on geology. Fascinating as has al- 

 ways been the study of marine life, this interest has 

 greatly increased since we have found the means of 

 reaching the abyssal fauna. Light has suddenly been 

 shed on many vexed problems concerning the geograph- 

 ical distribution of animals and plants and their suc- 

 cession in time from former geological periods to the 

 present day. New notions of geological horizons and 

 periods loom up before us, and the problems concern- 

 ing the formation of continents and oceanic basins now 

 present themselves from a very different standpoint. 

 Our ideas regarding the formation of many marine de- 

 posits have been greatly modified, and we are now 

 able to look back into the past history of the world 

 with more confidence than heretofore." 



As an example of the broad results of such work, it 

 may be mentioned, for instance, that ocean ographers 

 have discovered that the ocean depths are covered with 

 certain deposits ; such as the abyssal red clays, formed 

 from the decomposition of matter thrown out by vol- 



1 Agassiz coined and always used the word " thalassography " to de- 

 note the study of the ocean. But it never came into general use, partly, 

 perhaps, because of a mistaken impression that d&Xao-o-a referred only to 

 the Mediterranean, and partly because, for once, scientific men seem to 

 have preferred the simpler word " oceanography." 



