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1781, did much to give to geology the rank of a positive science. 

 In the mountain ranges of Siberia, Pallas discovered the general 

 law of the succession of the granitic, schistose, and calcareous 

 rocks a discovery which has given birth, as Cuvier affirms, to 

 all modern geology. In 1808 Berzelius, by the publication of his 

 admirable " System of Chemistry," greatly enlarged the bounda- 

 ries of chemical science. His vast analytical labors did much to 

 place the atomic theory upon a sure foundation. In Italy, near 

 the close of the last century, electrical science was measurably pro- 

 moted by the labors of Galvani and Yolta. The former, in 1791, 

 made known his curious researches upon the influence of electri- 

 city upon muscular motion ; while the latter, about the same time, 

 invented his well-known electric pile, by which he showed that a 

 disturbance of electrical equilibrium was produced by the mere 

 contact of different bodies, and that the electrical current circu- 

 lated in one constant direction through a circuit composed of dif- 

 ferent conductors. Between 1753 and 1812, anatomy, physiology, 

 and general natural history were cultivated with much success in 

 Europe by Linnaeus, Pallas, Spallanzani, Camper, Blumenbach, 

 Felix d'Azara, and others. In addition to his " System of Na- 

 ture," " Botanical Philosophy," and other valuable contributions 

 to the literature of botanical science, Linnieus, in 1753, published 

 the " Species Plantarum," in which, for the first time, was adopted 

 the happy idea of distinguishing species by adding a simple de- 

 scriptive word to the generic term. Camper and Blumenbach, in 

 addition to their other labors, cultivated ethnology with much 

 zeal. Blumenbach, especially, by the publication of his " Decades 

 Craniorum," laid the foundation of the science of human cranio- 

 graphy. It was during the great scientific epoch now under review 

 that the illustrious Humboldt entered upon his wonderful career 

 of extensive travel and varied scientific research. In the ten 

 years immediately preceding the founding of the Academy, he had 

 already published valuable works on the physical geography, geo- 

 logy, zoology, comparative anatomy, and ethnolog}*- of the northern 

 part of South America and Mexico, together with important memoirs 

 on the astronomical observations and barometric measurements 

 made by him in conjunction with his fellow-traveller, Bonpland, 

 during their five years' exploration of little-known regions of the 

 New World. These works, together with the " Aspects of Nature," 

 which first appeared in 1808, did more, perhaps, than the writings 



