TRAVELS IN BRAZIL 



dead to conelusions respecting their original coun- 

 trjji and their gradual diffusion qver the surface of 

 the globe. He proposed connecting these re- 

 searches >vith climatic and geogri^stici observations ; 

 and to this end to extend them to the itiosl: insig- 

 aiificant members of the Vegetable Icingdom, such 

 ) las mosses, lichens, and fungi, He was likewise to 

 observe the changes which both the native and 

 -exotic plants undergo, when exposed to certain ex- 

 '£erhal influences ; and to investigate the history of 

 vjhe soil, and the method of cultivation there in use. 

 iAn examination of the internal structure, and of 

 ,the development of tropical plants, promised in- 

 teresting solutions of the laws of vegetable life in 

 igeneral, as the observation of any traces that should 

 ibe discovered of an earlier vegetation, now extinct, 

 .miffht afford materials for the foundation of a 



CD . ' ( ■ 



.geognostic theory. Lastly, he conceived he should 

 vpromote the object of the mission by an accurate 

 jinvestigation of the Brazilian materia medica, 

 4rawn from the vegetable kingdom, as well as of 

 ^11 other vegetable substances, the use of which 

 might be interesting to arts and manufactures, and 

 .by carefully indicating the manner in which they 

 lare employed in their native country. But besides 

 the observations and researches in the departments 

 peculiar to each professor^ ip whicji reciprocal 

 assistance and support were presupposed, they 

 were particularly enjoined to complete, as far as 

 possible, the collections of the academy, by sendr 



