ON THE FECTJLA OF GREEN PLANTS. 273 



But it is too well known that I have not been able to fave 

 any thing in my flight from home, you will, however, be able 

 at a future day to afcertain the truth of the fact that I have 

 ftated to you. I thought that a fact of this nature deferved to 

 be depofited among your - archives, and I may perhaps requeft 

 of you the permiflion of depofiting there fome other frill more 

 curious fads. 



B*. DES LOZIERES. 

 Philadelphia, Feb. 3, 1797. 



XV. 



An Ejfay on the Fecula of Green Plants. By Profejfor Proust. 



HlLAIRE ROUELLE is the firft whodifcovered a fubftance Opinion of 

 in the green fecula analogous to the gluten of flour. This fub- f^^of ' 

 fiance, fince that time, has never appeared doubtful, becaufe plants contain 

 there are few chemifts who have not feen its true characters, albumen and 

 The fecula, of which it is the bafis, in the opinion of Four- Rouelle afierted, 

 croy, is only an imaginary being, or, at moft, it has been too 

 llightly examined to be admitted in the number of immediate 

 vegetable products ; he even proceeds fo far as to fuppofe that 

 the albumen, that animal product, which no one ever before 

 fufpected to be contained in plants, is the fubftance which 

 ought to be admitted inftead of the glutinous part of green 

 feculse. 



Are albumen and gluten found together or feparate in the are both found 

 juice of plants ? This is the queftion I have propofed to folve, ln P lants? 

 and I fhall endeavour to refolve it in this part of my obferva- 

 tions on his ff Syftem of Chemical Knowledge. " 



To fave my readers the trouble of turning to the work, I 

 fhall copy the paiTage in which the author has collected the 

 facts and arguments upon which he has formed his judgment. 

 This paflage is ftill more remarkable for the difference it pre- 

 fents between his manner of "characterifing other vegetable 

 products, and that of the chemifts of the prefent day. 



" Rouelle the younger, who examined and particularly Quotationf ton* 

 compared it with animal matters, aflerts that he has found itFourcroy. 

 in the coloured feculae, and efpecially in that which is called 

 the green fecula of plants. But the name of fecula being 



Vol. IV. — April. T given 



