}3$ On the Feculg. qf Green Plants, 



bellishes it with its different shades, has not been introduced 

 into the System of Chemical Knou' ledge, various chemists, 

 such as Rouelic, Daael, Sage, P^rmentierj &c. thought it 

 worthy of their researches. 



This resin, dissolved in potash, abandons it to attach it- 

 self to silk, and to give it a bright green dye ; but it fades 

 too much to become useful : it5 shade, however, resist^ 

 verjus : but the preference which ii at length gives to gluten 

 over the vegetable fibre is agreeable to known principles ; 

 for it is to aniinalized substances in general, rather than to 

 the fibres of flax, hemp, or cotton, that colouring bodies 

 attach themselves. Fecula then has something in its na- 

 ture analogous to wool, silk, &c.: it is gluten. 

 • V. Let us now examine fecula in points of view mor? 

 proper for unveiling new characters of animalization. 



If fecula, either boiled or raw, be kept under water, it 

 begin? in less than twenty-four hours to emit a bad odour. 

 It soon exhales an excrcmentitious putridity, which always 

 goes on increasing, and to which one perhaps could not 

 long be exposed without danger. The infectious miasn) 

 which it diffuses around it instantly obscures metallic writ* 

 ing, and its liquor speedily blackens plates of silver. 



Itjs to the corruption of this principle, no doubt, rather 

 than to any other, that are owing the pernicious exhalation^ 

 of hemp and flax when watered. As running water, whiclj 

 js equally proper as stagnant for separating the filaments, 

 speedily carries off their extractive juices, nothing but th© 

 green fecula whicli unites the fibres is susceptible of being 

 destroyed by watering. 



The liquor which at the end of a year floats above putrid 

 iiecula contains sulphurated hydrogen, carbonate of ammOi- 

 ^nia, and gluten dissolved bv means of the latter. 



It has this peculiarity also, that it retains its stercoraceou? 

 odour after long ebullition. The product of its distillation 

 xontains carbonate of ammonia joined to a principle of in- 

 fection which does not blacken metallic solutions, and with 

 the nature of which I am not acquainted. Acids are not 

 weakened by precipitating fecula and becoming saturated 

 with ammonia ; which induces me to think, that if tl;^e ef- 

 fluvia of a mass of animal putridity can serve as a vehicles 

 to the phosphorus and sulphur it contains, it is not in- 

 .debted for its infectious quality to these combustibles alone ; 

 that there is a great difference, for example, between the 

 odour of rotten fish or flesh, corrupted fecula or putrid 

 cheese, and that of phosphorated and sulphurated hydrogen. 

 [To be contiuuciJ J 



XXII. A 



