

165 



ALIMENTARY PRINCIPLES OF VEGETABLES. 



These are divided into those derived, 1st, from seeds, fleshy fruits, 

 roots, buds and young shoots, leaves, leaf-stalks and flowers, receptacles 

 and brats, stems ; and 2d, from ferns, lichens, alga, or sea-weeds, 

 and fungi, or mushrooms. 



Seeds used as food are farinaceous and oleaginous. Among the 

 most important of the farinaceous seeds are those of the cereal grains, 

 which we have already described, but to which, from their great im- 

 portance, we shall add some further useful particulars. 



The proximate principles of these valuable seeds are starch, albu- 

 men, fibrine, glutine, mucine, oily matter (which 3 last are included in. 

 gluten). Sugar, gum, earthy phosphates, ligneous matter (from husks, 

 &c.), and water. To these have been added resin and a bitter principle 

 found in some grains. 



Some alimentary substances composed of two simple elements, are 

 denominated simple aliments, and the union of these with others, 

 forms compound aliments. Water is a simple alimentary principle, 

 formed by the union of two elements; sugar and fat is composed of 3, 

 proteine of 4, and fibrine and albumen of 6 elements. These will be 

 alluded to in order. The simple are the undecomponnded or ultimate 

 elements, as the oxygen and hydrogen composing water, which water 

 and other compound substances constitute separately or when com- 

 bined, compound alimentary principles. 



The ultimate elements of the grains are stated in the last chapter. 

 Their constituents, termed nitrogenized or plastic elements of nutrfc h f [ g~~ 

 tion, are vegetable, albumen, fibrine, gluten and mucine, and their non- f 

 nitrogenized constituents or elements of respiration are starch, sugar 

 and gum. It appears that the average time of digestion of the grains 

 when prepared, are boiled : rice 1 hour, barley 2 h., and barley-soup 

 1 h. 30 m Baked : sponge cake 2 h. 30 m., custard 2 h. 45 m., apple- 

 dumpling 3 h., corn bread 3 h. 15 m., do. cake 3 h., wheat bread, fresh, 

 3 h. 30 m. 



The composition of wheaten bread with distilled water, but without 

 salt, is, starch 53, gummy starch 18, sugar 36, gluten 20. In 100 parts 

 of bread 30.15 are carbon. It does not appear that bread alone is 

 capable of supporting life for a long period, in consequence of the 

 small portion of nitrogen it contains. Oat meal is thought to be as 

 nutritive as wheat flower, since it is found to contain about the same lUw-^ 

 quantity of nitrogen. But having elsewhere spoken of the grains, the ' 

 legumes, and of bread, we shall reserve further remarks on this sub- JL/O 

 ject and the fruits for a future volume. The average composition of 

 peas and beans may be assumed to be, in 100 parts starch 34, amyla- 

 ceous fibre 16, legumine 15, gum 5, (kidney bean 19), albumen 1, sweet 



