previously acquainted with the simple fos- 

 sils, which compose the mass of mountains, 

 and of which the names and character are 

 the object of oryctognostical knowledge. 

 It is the same with that part of the natural 

 history of the globe, that treats of the rela- 

 tions the plants have to each other, with the 

 soil whence they spring, or the air which 

 they inhale and modify. The progress of 

 the geography of plants depends in a great 

 measure on that of descriptive botany ; and 

 it would be injurious to the advancement 

 of the sciences to attempt rising to general 

 ideas, in neglecting the knowledge of par- 

 ticular facts. 



I have been guided by these considera- 

 tions in the course of my inquiries ; they 

 were always present to my mind at the 

 period of my preparatory studies. When 

 I began to read the numerous relations of 

 voyages, which compose so interesting a 

 part of modern literature, I regretted that 

 travellers, the most enlightened in the in- 

 sulated branches of natural history, were 

 seldom possessed of a sufficient variety of 

 knowledge, to avail themselves of every ad- 

 vantage arising from their position. It ap-* 



