74 The Founders of Geology LECT. 



spersed comment and criticism in his notices are specially 

 valuable. 



The other three volumes were devoted to descriptions of 

 places, districts, and countries, and to articles or subjects 

 in Physical Geography a branch of knowledge which 

 Desmarest regarded as embracing two equally important 

 and closely related subjects the interior structure of the 

 globe and its external form. Geology was not yet admitted 

 to a formal place among the sciences, but geological 

 questions occupy a prominent place in the massive quartos 

 of the Encydopddie Mtthodigue}- 



The delays that attended the publication of Desmarest's 

 important and original observations and deductions respect- 

 ing the volcanic geology of Auvergne reached their climax 

 in the case of his detailed map of that region. We have 

 seen that at his instigation a topographical survey of 

 Auvergne on a large scale was begun as far back as 1764, 

 and that reductions of this map accompanied his Memoirs 

 presented to the Academy of Sciences. The map itself, 

 however, with all its elaborate detail, bearing on the 

 history of the volcanoes of Central France, still remained 

 in his hands. Year after year he sought to bring it nearer 

 to his ideal of perfection. Every part of the region had 

 been scrupulously examined by him, every puy was set 

 down, every crater was carefully drawn, every current of 

 lava was traced out from its source to its termination, 



1 Vol. i. of the Geographic Physique appeared in An III (1794) ; vol. ii. 

 in 1803 ; vol. iii. in 1809, and vol. iv. in 1811. Among the geological 

 articles of interest in these volumes reference may be made to those on 

 Antrim, Auvergne, Basalte, Chaussee des Geans, and Courans. Vol. v., left 

 unfinished by Desmarest, was continued by Bory de St. Vincent, Doin, 

 Ferry, and Huot, and was not published until 1828. 



