54 Fecula of Vegetables. [Book VII!. 



white or coloured fluid, which by (landing depofits 

 a fubftance more or lefs fibrous or pulverulent, accord- 

 ing to the nature of the vegetable fubftance from 

 which it was obtained. This is called the fecula of 

 vegetables, and confifts almoft entirely of ftarch. 

 Some parts of vegetables appear to be altogether/ 

 compofed of this matter j fuch as the feeds of the 

 gramineous and leguminous plants, tuberous roots* 

 &c. Thefe parts in general afford the fineft and moft 

 abundant fecula. The ftems and leaves of vegetables 

 afford only a coarfe filamentous depofition, but if this 

 is powdered and warned, the water carries off a fine 

 fecula, perfectly fimilar to that afforded by grain. Alt 

 vegetables therefore, and all the parts of them, afford 

 more or lefs of this matter ; the only difference is, 

 that in fome parts it is naturally difengaged from other 

 fubftances, in others it is in fuch a (late, that it mufl 

 be feparated by a laborious procefs. The fecula of 

 fome vegetables is feparated as' an article of food : as 

 from the root of briony, from potatotes, from the root 

 of a very acrid plant called manioc, from the pith of 

 a kind of palm which grows in the Moluccas, which 

 affords the fecula called fago j and from the Toot of 

 a fpecies of or?his, which affords falep. 



IX. FARINA. Flour, or the pulverized fubftance 

 of farinaceous feeds, has a ftrong analogy with the 

 gummy and faccharine mucilages. Farinaceous feeds, 

 if kept in a moderate temperature, and fupplied with 

 moifture, are, by the incipient procefs of vegetation^ 

 converted in a great meafure into faccharine mucilages, 

 as happens in making malt. Wheat-flour is the moft 

 perfect farina with which we are acquainted, and I 

 lhall therefore confine my defcription to it $ though it 



mull 



