CHEMISTRY. 



[LBOl'MINOCS SEEDS. 



the legumin, which in a constituent of all logu- 

 niinou* wyxlt, U contained in peas, beans, and lontiU, 

 in to abundant a quantity, that thU albuminous sub- 

 sUnoa not seldom surpasses both tho proportion of gluten 

 in broad, and that of tibrino in moat Legumin u 



bread, 

 soluble in water, 



\ . 



itate* a audimont in 

 Ve again if a larger 



the solution, which doe* not 



quantity of thi* acid be added. By more boiling, the 

 legurain doe* not coagulate ; but this effect U produced 

 on the lolnbte vegetable albumen, which, at in cereal 

 grains, U also found in the leguminous *eod in a small 

 proportionata quantity. 



A considerable proportion of starch, accompanied by a 

 good quantity of gum, and in the sugar-peas, for in- 

 stance, by sugar also, takes the place of the constituent* 

 of fat, in the interior of the seeds of peas, beans, and 

 lentils. The husk of these seeds, as well as the shell of 

 those beans which are eaten whole, consist in great pait 

 of a substance which forms in all plants tho ymin; 

 cellular walls, and is therefore called tho cell principle, 

 or cellulose. This belongs to the constituents of fnt ; it 

 is identical in composition with starch, and like this is 

 transformed into sugar by acids. But this process of 

 transformation is so slow, that the cellulose, which does 

 not dissolve in water, belongs to tho alimentary sub- 

 stances, which are very difficult of digestion ; so much the 

 more so, as oven the alkali of our saliva, bile, pane: 

 and intestinal juices, U only able to dissolve a very small 

 quantity of cellulose. 



The ready-formed fat associated in tho leguminous 

 seeds with the constituents of fat, U present in so small 

 a quantity, that, without their abundant proportion of 

 starch and gum, the Peas, beans, and lentils would not 

 be able to restore the fat of the body, which, after being 

 decomposed by combustion into carbonic acid and water, 

 we constantly exhale. 



All the compounds of chlorine and salts of the blood 

 are 'to be found in the leguminous seeds ; the most 

 abundant salts of the blood, the phosphates of tho alkalies 

 and earths, existing there in the greatest abundance. 



} 60. Alimentary Principles. Legumin owes its name 

 to the circumstance of its representing the most impor- 

 tant alimentary principle of the leguminous seeds ; for 

 it represents the albuminous substance* in the peas, the 

 beans, and the lentils, which contain only a small pro- 

 portion of soluble albumen besides. 



How is it that peas, beans, and lentils, become hard by 

 boiling, as tho leguinin does not coagulate under tho in- 

 fluence of boiling-water, and the proportion of tho 

 coagulating soluble albumen is so small f Because tho 

 chemist and the cook employ a water altogether different 

 The chemist operate* only with water free from all dis- 

 solved substances. He first causes tho rain or spring- 

 water to evaporate by heat, and condenses again the 

 vapour so formed in a low temperature ; the water thus 

 distilled containing none of those compounds of lim 

 which are found in all the water used by the cook. But, 

 in boiling, tho lima unites with tho leguinin, and trans- 

 forms it into a very hard substance ; and as rain- 

 water contains a smaller quantity of limo than spring- 

 water, the peas remain softer in the former than in the 

 latter. 



Hy the process of boiling in rain-water, which contains 

 but a small pr. ;:!: >n of limo, a considerable part of the 

 legumin is dissolved. It is bettor, tlieruforo, both for 

 tho blood and the purse, to oat peas, beau*, and lentils 

 not in a dry form, but prepared as soup. Just as boiled 

 moat should be partaken together with its broth, in 

 to got tho most digestible and nutritive part of the i 

 so in pea and lentil soups, tho fluid part i* better than 

 the undissolvod portion. A great part, therefore, of the 

 nutritious substance is thrown away if we only eat tho 

 peas which have been boiled in water, and throw tho 

 liquor away. 



S 67. DyeitMlUy of Legvminoia Seed*. In respect of 

 digestibility, the leguminous seed*, if taken without 

 bosks or skins, hold an intermediate place between meat 

 and bread ; for tho tibrino and albumen have an advan- 

 tage ovor logumin in their greater conformity with the 



constituents of the blood, while logumin surpasses the 

 f tho bread in solubility. 



But if water which contains much limo, as is often the 

 case, renders the legumin h ml. an<l if the seed* are 

 rendered more difficult of solution by tho presence of 

 thoir husks, pea*, beans, and lentils become dishes dif- 

 ficult of digestion, and occasion flatulence. ThU show* 

 the advantage of preparing the soups of the leguminous 

 seed* in rain-water, and straining them through a hair- 

 sieve after tho bursting of the husks by boiling. Peas, 

 beans, and lentils, with thoir husks, require very vigorous 

 organs to digest them. 



But tho leguminous seeds, though inferior to meat in 

 digestibility, are superior in the abundance of solid con- 

 stituents which they contain ; for the proportion of 

 water in peas, beans, and lentils, is scarcely one-sixth of 

 thoir weight ; and while the quantity of albuminous sub- 

 stances may surpass that contained in meat by ono-lutf, 

 the constituents of fat and the salts are also present in 

 the leguminous seeds in a greater abundance. 



Blood and flesh, and milk, are therefore abundantly 

 formed by peas, beans, and lentils ; and for this reason 

 they are the comfort of poor people, to whom meat is so 

 seldom and so sparingly allotted. 



We have already mentioned the considerable propor- 

 tion of phosphorus contained in logumin ; but the brain 

 cannot exist without tho peculiar fat containing ; 

 phorus, which owes its origin to the albumen ami ti 

 of tho blood. Phosphorus cannot bo formed from any 

 other element It necessarily follows, therefore, that i 

 i.r.'.id, and leguminous seeds are serviceable in supporting 

 the nutrition to the brain ; and that aliments like lisli and 

 eggs, which contain a ready-formed phoiphuretted fat, 

 will facilitate the conveyance of this peculiar constituent 

 of the brain. The formation, ami therefore the activity 

 of the brain, also, is dependent on this fat containing 

 phosphorus ; and it has been said, as a mere pleasantry, 

 that a sagacious man has much phosphorus in his brain. 

 The chemical combination of an organ is as much im- 

 paired by containing too much of a constituent, as by 

 possessing too little. There is no danger that tho laws 

 of regular attraction, upon which the nutrition of tho 

 tissues U dependent, should allow the excessive supply 

 of a single constituent ; but the function suffers if this 

 constituent be present in too small a proportion. Vi 

 cannot, therefore, presume an abundance of phosphorus 

 in great thinkers ; while yet it remains true, that with 

 no phosphorus, there is no thought active in the brain. 



68. Vegetable*. Meat and vegetables are aliments so 

 generally used together, as inevitably to suggest tho pre- 

 sumption that one is complemented by thu other ; and 

 on investigating tho composition i if tho diil'erent kinds of 

 vegetables, such a* cabbage, cauliflower, salad, spinach, 

 sorrel, and asparagus, nine-tenths of their weight will )> < 

 found to consist of water, with scarcely half-a-nund 

 part of soluble albumen. Although tho proporti 

 the constituents of fat, especially of cellulose and gum. 

 in addition to starch, wax, and the greou nitrogenised 

 matter of tho plants, exceeds the albumen in quantity, 

 yet it is evident, from the considerable abundam 

 water, that the constituent* of fat form only a very 

 small proportionate part of tho above-mentioned vego- 

 i .' . -. 



Hut tho loaves and young shoot* which are used as 

 dishes of vegetables, contain several organic acids ; 

 asparagus, for instance, with all the cabbage tribe, pos- 

 sesses acid of apples, or malic acid ; tho sorrel, oxalic 

 acid ; rhubarb contains both malic and oxalic acids. 

 M.ilio acid consists of carbon, hydrogen, ami a 

 proportion of oxygen; while oxalic acid, like carbonic 

 acid, is composed of carbon and oxygon only, but with 

 a smaller proportion of oxygon than is contained in 

 c irlioniu acid. Both these vegetable acids have tho 

 of keeping the soluble albumen of meat in a dis- 

 solved state. In asparagus tl> I nii'i tin- 

 malic acid another body, tho asparagino, neither acid 

 nor alkaline, but remarkable for its amount of nitrogen. 

 I ly, the saurkrout, the dainty of a German citizen, 

 and tho relief of an English sailor, derives its name from 



