SEQUEL TO SYSTEMATIC GEOLOGY. 527 



correction and confirmation of Smith's labors, but a valuable store- 

 house and standard of what had then been done in English geology. 

 Leopold von Buch had constructed a geological map of a large por- 

 tion of Germany, about the same period ; but, aware of the difficulty 

 of the task he had thus attempted, he still forbore to publish it. At 

 a later period, and as materials accumulated, more detailed maps of 

 parts of Germany were produced by Hoffmann and others. The 

 French government entrusted to a distinguished Professor of the 

 School of Mines (M. Brochant de Villiers), the task of constructing a 

 map of France on the model of Mr. Greenough's ; associating with 

 him two younger persons, selected for their energy and talents, MM. 

 Beaumont and Dufrenoy. We shall have occasion hereafter to speak 

 of the execution of this survey. By various persons, geological maps 

 of almost every country and province of Europe, and of many parts of 

 Asia and America, have been published. I need not enumerate these, 

 but I may refer to the account given of them by Mr. Conybeare, in 

 the Reports of the British Association for 1832, p. 384. These vari- 

 ous essays may be considered as contributions, though hitherto un- 

 doubtedly very imperfect ones, to that at which Descriptive Geology 

 ought to aim, and which is requisite as a foundation for sound the- 

 ory ; a complete geological survey of the whole earth. But we 

 must say a few words respecting the language in which such a survey 

 must be written. 



As we have already said, that condition which made such maps and 

 the accompanying descriptions possible, was that the strata and their 

 contents had previously undergone classification and arrangement at 

 the hands of the fathers of geology. Classification, in this as in other 

 cases, implied names which should give to the classes distinctness and 

 permanence ; and when the series of strata belonging to one country 

 were referred to in the description of another, in which they appeared, 

 as was usually the case, under an aspect at least somewhat different, 

 the supposed identification required a peculiar study of each case ; and 

 thus Geology had arrived at the point, which we have before had to 

 notice as one of the stages of the progress of Classificatory Botany, 

 at which a technical nomenclature and a well-understood synonymy 

 were essential parts of the science. 



Sect. 3. Geological Nomenclature. 

 Br Nomenclature we mean a system of names ; and hence we :an 



