LECTUEE Y 



The rise of stratigraphical geology The work of Giraud-Soulavie, 

 Cuvier, Brongniart and Omalms d'Halloy in France ; the 

 labours of Michell and William Smith in England. 



THAT the rocks around and beneath us contain the record 

 of terrestrial revolutions before the establishment of the 

 present dry land, was an idea clearly present to the minds 

 of the early Italian geologists, and was generally admitted, 

 before the end of last century, by all who interested them- 

 selves in minerals and rocks. The Neptunists and Vulcan- 

 ists might dispute vigorously over their respective creeds, 

 but they all agreed in maintaining the doctrine of a 

 geelogical succession. Werner made this doctrine a 

 cardinal part of his system, and brought it into greater 

 prominence than it had ever held before his time. His 

 sequence of formations from granite, at the base, to the 

 youngest river-gravel or sea-formed silt betokened, in his 

 view, a gradual development of deposits, which began with 

 the chemical precipitates of a universal ocean, and ended 

 with the modern mechanical and other accumulations of 

 terrestrial surfaces, as well as of the sea-floor. But, as we 

 have seen, the lithological characters on which he based 

 the discrimination of his various formations proved to be 

 unreliable. Granite was soon found not always to lie at 



