36 HISTOBY OF THE SCIENCE. 



WERNER, who succeeded to the professorship of miner- 

 alogy at Freyberg, in Saxony, in 1775, directed his views 

 from that science to geology, and the general structure 

 of the earth ; and, by his genius and eloquence, obtained 

 for a lengthened period universal favour and popularity. 

 As the summary of his system, it may be stated, that water 

 was considered the universal agent in the formation of 

 rocks, which from the granite up to the most recent beds, 

 were regarded as aqueous deposits ; while volcanoes, which 

 constitute so important a cause in their production, were 

 conceived to be merely of recent date, and to have been 

 quite unknown and inoperative in the ancient history of the 

 earth. From the universal agency thus ascribed to water, 

 his followers were termed Neptunists ; while their oppo- 

 nents, who advocated the igneous origin of many rocks, and 

 maintained the action of fire, were termed Vulcanists. 



The faults of Werner and his system, the dogmas of the 

 universal operation of water, and the utter exclusion of an 

 agent so obvious as fire, have long since been exploded. His 

 errors, both of theory and practice, are to be ascribed to the 

 position of the man, and the prejudices which that position 

 induced. As a mineralogist, he was led by his peculiar bias 

 for classification, to apply a strict and contracted method of 

 arangement to phenomena, too vast and varied for so narrow 

 a limitation ; and, in practice, he formed his conclusions as 

 to the structure of the whole earth, from the partial investi- 

 gation of a single district. Hence, his system has met with 

 the fate of all those which form extensive generalisations on 

 few and insufficient data, and which attempt to explain the 

 vast operations of nature from observations of local extent 

 and limited influence. He formed a world on the model 

 of the valleys of Saxony, rejected the possibility of igneous 

 rocks, when the inspection of the trap-dikes in the Hartz 

 mountains would have convinced him of their reality ; and 

 denied the existence of ancient volcanoes, when a journey 

 to Auvergne would have satisfied him of their existence. 

 He was, however, a man of a very high order of mind, gifted 

 with genius, energy, and eloquence ; while, as a mineralogist, 

 he was eminently acute and skilled in the power of classi- 

 fication and arrangement, as well as in determining the order 

 and succession of local deposits. His errors have served 



