Martius on the Life and Labours of DeCandolle. 5 



his treatise upon the nourishment of Lichens, \vhich, in the sum- 

 mer of 1797, was laid before the Societe tie Physique et d'Histoirc 

 Natiu-elle, then recently established by Saussurc at Geneva. His 

 intercom-se with Senebier and Vaucher coulinned him in this di- 

 rection of his faculties. It is easy to perceive, that, in the whole 

 course of his literary labour's, he sought to make the doctrines of 

 physics and of chemistry available in their application to botany. 

 ^Ye find the same spirit in his excellent treatise ' Sur les Proprietes 

 Medicales des Plantes' (Paris, 1804, 4to), of which Perleb has 

 given a German version (1810) enriched with many valuable ad- 

 ditions. He attempted in this work to represent more fully than 

 had been before done, the parallel suggested by Liunreus, but op- 

 posed by other \\Titers, between the outward forms of plants and 

 their chemical constitution and adaptation to pharmacy ; a labour 

 in which he manifested a happy talent for tracing back various 

 phreuomena to their origin in general principles. 



In the year 1798 Geneva was incorporated into the French re- 

 public. DeCandolle, findmg his futm-e prospects much affected 

 by this event, the property of his parents ha\iug been materially 

 diminished by the catastrophes of the E evolution, determined to 

 adopt the mechcal profession, and easily obtained the consent of 

 his father, Avho hoped that he would be thus established in a lu- 

 crative mode of life. The son, meanwhile, whose enthusiasm for 

 botany had increased from year to year, thought principally of 

 the greater facilities he shordd thus enjoy for the pursuit of his 

 favom-ite science. During this year he went the second time to 

 Paris ; and taking up his abode in the neighbourhood of the Jardin 

 des Plantes, he gave himself up with zeal to the study of its ac- 

 cumulated treasm'es. Lamarck encoiu-aged him to labour with him 

 in the botanical portion of the ' Encyclopedic Methodique,^ in 

 which he ^^TOte the articles Parthenium and Lepidivm. He also 

 assisted Lamarck in the preparation of the article on Panicum, 

 Pou-et in that on Paspalum, described the species of Senebiera, and 

 published his treatise on Lichens. At the request of Desfontaines 

 he undertook the preparation of the text for the ' Plantes Grasses,^ 

 which Redoute had begun to represent in a splendid iconogra- 

 phical work. He received on this occasion the most friendly as- 

 sistance from Desfontaines and L^Heritier, who gave him the free 

 use of their rich collections and invaluable books. If neither this 

 work, nor that on the Liliacea, which Redoute published some- 

 what later (also with the assistance of DeCandolle), nor the As- 

 tragalogia pubhshed in 1802, merit the praise of exact analytical 

 descriptions of individuals, such as science now demands of mo- 

 nography, yet they already foreshow the facility and acuteness of 

 systematic comprehension which so fidly characterize DeCan- 

 dolle's later efforts. 



