Biographical Memoir ofM. Halle. 5 



us he successively treated the greatest questions of medical 

 science, whether in the reports that were asked of him, or m 

 memoirs in which he explained his own views. His reports on 

 the cowpox are the most important of aU. He had upheld it, 

 in some degree, from the time of its introduction, in 1800, and 

 had made known its beneficial efFects. In 1812, when these 

 had been established by an experience of some duration, he re- 

 examined the subject, shewed the nature of the exceptions, 

 ascertained their causes, and thus contributed to gam, for that 

 admirable preservative, tl>e confidence that was due to it. He 

 may be regarded as one of its most successful promoters; and 

 France will name him with the WoodviUes and the Rochefou- 

 caults. On this account, Italy, too, owes him especial gratitude. 

 In 1810, he was summoned to extend vaccination in the state 

 of Lucca and in Tuscany ; and the public experiments he made 

 there, together with the detailed account he gave of them, for- 

 warded its popularity in that country. 



In his lectures at the faculty, M. Halle viewed medicine as a 

 subject of observation, and dwelt chiefly on those phenomena of 

 the animal economy which can be referred to the known laws of 

 the physical sciences. Physicians have, according to him, too 

 much undervalued the application of these sciences. " The 

 problem of nature," says he, " is a compound of the known and 

 the constant, with the unknown and the vanable ; and it is a 

 great error to imagine, that, to resolve it, to obtam the value ot 

 The unknown, and to fix the shades of the variable, the constant 

 and calculable elements are to be neglected." In this lay the 

 fundamental principle of his course. He did not publish his 

 lectures, but the articles which his pupils extracted from them 

 for the Didimnaire des Sciences Midicales, will serve to afford 

 some idea of the whole course *. In these articles are seen com- 

 bined the most enlarged views, a sound judgment, and vast 

 erudition. He always keeps pace with the advance of the 

 sciences, and brings them to his subject in the most ingemous 



manner. , • i • i » 



His erudition was still more eminently displayed in his lectures 



. Especially the articles Hygiene, Matifere de Hygiene, Alimens, Bains. 

 Percepta, Electricite, Physique Medicalc, Afrique, Europe, &c. 



