Memoir on the Geographical Extent of the 

 Formation of the Environs of Paris. — By 

 J.J. D'Omalius D'Halloy. 



Bead at the Institute, August 16, 1813. 

 (Annales des Mines, 1816.) 



THE learned researches of Messrs. Cuvier and Brongniart, 

 have drawn general attention to the formations in the en- 

 virons of Paris, and this is not remarkable ; for if the lofty 

 Alps, where nature presents herself under such magnificent 

 forms, have inspired the great de Saussure, the true creator 

 of geology as a science of observation ; if Saxony, a country 

 excavated to vast depths, in consequence of its mineral 

 riches, has offered to the genius of Werner, an opportunity 

 of establishing the first good system of geology ; the environs 

 of Paris, containing such abundant remains of living crea- 

 tures, have given birth to true philosophical geology, that 

 •which drawing its conclusions from the knowledge of the 

 organised bodies entombed in the bosom of the earth, can 

 alone afford the certain means of comparison between distant 

 formations, and will one day perhaps throw some light on 

 the various catastrophes that have changed the surface of the 

 globe, as it has already indicated the nature of the liquids in 

 which some of these phenomena have occurred. 



The geographical extent of the formations in the environs 

 of Paris, and the details into which Messrs. Cuvier and 

 Brongniart have entered in their geological map, have not 

 allowed them to represent the entire limits of this formation. 



