On the Fecula of Green PhinlS. sy 



IX. Water employed in washing fiirina, like the juice 

 Tx;cently filtered, is in a state ot alteration, which continually 

 increases, and which does not stop till the acid which arises 

 from the fermentation of the saccharine principle has 

 finished the precipitation of the gluten. 



All the acids and all the salts which we have applied to 

 juices operate in the same manner on the water of farina. 

 Alcohol produces the same effect : but vinegar does not, 

 because it dissolves the gluten. In a word, it is not by 

 coagulation that acids separate gluten from juices and from 

 the water of farina, since annnonia and salts do the same; 

 but rather by seizing on the solvent of a substance which 

 seems to derive its solubility from a pure and simple division, 

 and not from an affinity comparable to that which unites 

 gums, sugar, and albumen to water. 



Water of farina exposed to a heat of 145 degrees aban- 

 dons the gluten as it does the juice of plants. To dilute it 

 in a verv large quantity of water is not sufficient to give 

 solubility to gluten : on the least exposure to heat it falls of, 

 itself. 



I have collected so much as an ounce of gluten whick 

 heat separated from washings. Kept in its own moisture 

 it fermented, produced vinegar and ammonia. It is now 

 after two years an obscure cellular mass, odorous and savoury 

 in the same degree as the cheese of gluten. 



Let us then conclude that albumen has not yet appeared 

 in vegetables. But we shall not therefore say that it cannot 

 be formed there as well as in animals. The age in which 

 we live, being more abundant than ever in observations, 

 daily proves that there are but few products in either king- 

 dom which can be considered as really exclusive. It will 

 however be allowed, that to establish the existence of al- 

 bumen by excluding the gluten of green plants, the learned 

 author of the System of Chemical Knowledge has trusted 

 too much to the slender support of mere appearance. Before 

 he announced albumen he ought, in my opinion, to have 

 etrcngthened his first observation by more conclusive facts 

 than that of concrescibility alone. But let us not forget that, 

 in so vast an cnterp/ise as this, it is difficult for an author 

 to cut out with equal. precision all the jnaterials of his cxli- 

 fice. 



It will be with the same view that I shall extend these 

 conclusions to other products which Fourcroy, without suf- 

 ficient examination, has placed among the glutinous sub' 

 etaiices of vegetables, 



^' There 



