190 COSiMOS. 



of the breaking forth of originally closed seas ; of the general 

 level of the sea, which was already recognized by Archimedes ; 

 of oceanic currents ; of the eruption of submarine volcanoes , 

 of the petrifactions of shells and the impressions of fishes ; and, 

 lastly, of the periodic oscillations of the earth's crust, a subject 

 that most especially attracts our attention, since it constitutes 

 the germ of modern geognosy . Strabo expressly remarks that 

 the altered limits of the sea and land are to be ascribed less 

 to small inundations than to the upheaval and depression of 

 the bottom, for " not only separate masses of rock and islands 

 of different dimensions, but entire continents, may be upheav- 

 ed." Strabo, like Herodotus, was an attentive observer of the 

 descent of nations, and of the diversities of the different races 

 of men, whom he singularly enough calls " land and air ani- 

 mals, which require much light.'.'* We find the ethnological 

 distinction of races most sharply defined in the Commenta- 

 ries of Julius Csesar, and in the noble eulogy on Agricola by 

 Tacitus. 



Unfortunately, Strabo's great work, which was so rich in 

 facts, and whose cosmical views we have already alluded to, 

 remained almost wholly unknown in Roman antiquity until 

 the fifth century, and was not even then made use of by that 

 universal collector, Pliny. It was not until the close of the 

 Middle Ages that Strabo exercised any essential influence on 

 the direction of ideas, and even then in a less marked degree 

 than that of the more mathematical aniJ more tabularly con- 

 cise geography of Claudius Ptolemaeus, which was almost 

 wholly wanting in views of a truly physical character. This 

 latter work served as a guide to travelers as late as the six- 

 teenth century, while every new discovery of places was al- 

 ways supposed to be recognized in it under some other appel- 

 lation. 



In the same manner as natural historians long continued 

 to include all recently-discovered plants and animals under 

 the classifying definitions of Linnseus, the earliest maps of the 

 New Continent appeared in the Atlas of Ptolemy, which 

 AgathodsBmon prepared at the same time that, in the remot- 

 est part of Asia among the highly-civilized Chinese, the west- 

 ern provinces of the empire were already marked in forty-four 

 divisions. t The Universal Geography of Ptolemy has indeed 

 the advantage of presenting us with a picture of the whole 

 world represented graphicaUy in outlines, and numerically in 

 determinations of places, according to their parallels of longi- 



* Strabo, lib. xvii., p. 810. t Carl Ritter, Asien, th. v., s. 560. 



