MODERN SCIENCE. 161 



.Hutton, his master, that he is chiefly to be remembered, for 

 being an excellent expositor he had much influence in 

 advancing the study of the earth. 



1748 1 8 . Keferstein, in his Geognostic Remarks upon 

 the basalt formations of Western Germany, demonstrated the 

 volcanic FORMATION OF BASALT against the Neptunian 

 .school of Werner. 



1750 1817. Werner, by observing, like Hutton, the crust 

 of the earth instead of guessing natural processes, power- 

 fully helped to make geology an experimental study, and 

 ground that science on firm foundations. He originated the 

 NEPTUNIAN THEORY, which consisted in believing water to 

 .have been the almost exclusive cause of new formations, and in 

 .leaving aside other concurrent causes. His sweeping theory 

 Is now recognised to be correct only as regards sedimentary 

 rocks, but his fine lectures promoted the advance of the 

 science, for Hutton himself received much profit from Werner's 

 teaching and theories. 



1760 1832. Hall (Sir James) founded EXPERIMENTAL 

 GEOLOGY by devising experiments in illustration of the 

 structure and origin of rocks ; and this constitutes another 

 service done by Hutton's school to the progress of science. For 

 owing to the influence of the Wernerian school, and Hutton's 

 want of style, Huttonian theories were little known. His 

 friend Hall showed their soundness ; he demonstrated basalt 

 to have been once in a molten condition, by fusing some, and 

 pointing that it exhibits a stony texture by slow cooling. 

 He carried out similar experiments upon limestone convert- 

 ing it into marble under great pressure, and showing it to 

 act on other rocks. Hutton's theories began from that time 

 to command the attention they deserved ; but it was only 

 after Playfair's exposition of them that Hutton was at last 

 recognised as a great authority, and appreciated as an earnest 

 and unerring investigator. 



17691832. Cuvie'r threw great light on geology by his 

 almost exhaustive study of FOSSILS, but wrongly ascribed 

 changes in the stratification to sudden cataclysms. Lyell, 

 since then, has demonstrated the transformation to be due to 

 .slowly-acting laws. 



