Ohservations on Fermtiilation. 221 



Community, will induce the public to prefer a mild disease 

 like vaccination, which where it fails of superseding the 

 small-pox, yet mitigates its violence, and prevents its fatal 

 consequences, to one whose effects are frequently violent; 

 to one which often occasions deformity and bluidness ; and, 

 when it is contracted by casual infection, has been sup- 

 posed to destroy one in six in all that it attacks. And it must 

 not be forgotten, that in a public view this constitutes the 

 great objection to inoculation of the small-pox, that by its 

 contagion it disseminates death throughout the empire, 

 whilst vaccination, whatever be the comparative security 

 which it afibrds to individuals, occasions no subsequent 

 disorder, and has never, by the most violent of its opposers, 

 been charged with producing an epidemical sickness. 

 By Order of the Board, 

 July 18, 1811. Jas. Hervev, Register. 



XLT. Observations on the Article " Fermentation," con- 

 tained in M. Chaptal's Nouveau Cours cumplet d'A<yrl- 

 culture. By M. Dupoktal, M. D. Professor of Pliysic 

 and Chemistry in the Academy of MonlpeUier, &c. * 



J. HE equilibrium in the composition of vegetable sub- 

 stances is speedily destroyed when their life escapes from 

 them. These substances very soon' undergo a chane;e in 

 their appearance, the principles which compose them react- 

 ing upon each other ; they are arranged in a new order, a\id 

 in new proportions, whence result products very dilferent 

 from tliose substances which gave rise to their production. 



These products vary according to the nature of the sub- 

 stances, and according to the various circumstances which 

 accompany their change. Thus, vegetable substances which 

 are decomjioscd in some pecuhar circumstances, undergo 

 a spontaneous alteration which is called fermentation, of 

 w hich the product is bread, an intoxicating liquor, or vine- 

 gar, according to ihe matter subjected to fermentation ; 

 while recent herbaceous plants, which putrefy, give rise to 

 the formation of mould. 



These are the facts pointed out by M. Chaptal in the 

 work I am now to analyse. Examining first the fermen- 

 tation of vegetables of a fleshy and juicy texture, when 

 collected into a large heap, he details the conditions, the 

 phenomena, and the result of the process. He afterwards 

 considers the operation in each of the separate parts of 



• Annalts tie Chimie, 1810, 



which 



