I* NUTRIENTIA. Art. 1. 2. 3. 5* 



the medicinal parts of them. Thus if the root of white briony 

 be rat'ped into cold water, by means of a bread-grater made of 

 a tinned iron plate, and agitated in it, the acrid juice of the root 

 along with the mucilage will be diflblved, or fwim, in the water ; 

 while a ftarch perfectly wholefome and nutritious will fubfide, 

 and may be ufed as food in times of fcarcity. 



M. Parmentier further obferves, that potatoes contain too 

 much mucilage in proportion to their ftarch, which prevents them 

 from being converted into good bread. But that if the ftarch 

 be collected from ten pounds of raw potatoes by grating them 

 into cold water, and agitating them, as above mentioned ; and 

 if the ftarch thus procured be mixed with other ten pounds of 

 boiled potatoes, and properly fubjecSted to fermentation like 

 wheat flour, that it will make as good bread as the fineft wheat. 



Good bread may alio be made by mixing wheat-flour with 

 boiled potatoes. Eighteen pounds of wheat-flour are faid to 

 make twenty-two pounds and a half of bread. Eighteen pounds 

 of wheat-flour mixed with nine pounds of boiled potatoes, are 

 laid: to make twenty-nine pounds and a half of bread. This 

 difference of weight muft arife from the difference of the previ- 

 ous drynefs of the two materials. The potatoes might proba- 

 bly make better flour, if they were boiled in fleam, in a clofe 

 veffel, made fome degrees hotter than common boiling water. 



Other vegetable matters may be deprived of their too great 

 acrimony by boiling in water, as the great variety of the cab- 

 bage, the young tops of white briony, water-crefies, afparagus, 

 with innumerable roots, and fome fruits. Other plants have 

 their acrid juices or bitter particles diminifhed by covering 

 them from the light by what is termed blanching them, as the 

 items and leaves of cellery, endive, fea-kale. The former 

 method either extracts or decompofes the acrid particles, and 

 the latter prevents them from being formed. See Botanic 

 Garden, Vol. I. additional note XXXIV. on the Etiolation of 

 vegetables. 



5. The art of cookery, by expofing vegetable and animal 

 fubftances to heat, has contributed to increafe the quantity of 

 the food of mankind by other means befides lhat of deftroying 

 their acrimony. One of thefe is by converting the acerb juices 

 of fome fruits into iugar, as in the baking of unripe pears, and 

 the bruiting of unripe apples ; in both which fituations the life 

 of tiie vegetable is deltroyed, and the conversion of the harlh 

 juice into a fweet one muft be performed by a chemical procefs ; 

 and not by a vegetable one only, as the germination oi barley in 

 making malthas ^werally been fuppofed. 



une circumftances, which feem to injure the life of feveral 



fruit ij 



