VEGETABLES. 



Thefe fubllances comprife fome of the mofl important 

 articles of food in different intentions, and it is fuggefted as 

 probable, that the excellence of them in this view will be 

 found, in a great meafure, to be in proportion to the quan- 

 tities of this fort of matters they yield or afford ; though 

 they cannot be regarded as abfolutely denoting their value 

 in this way. Some of the matters have the charadlers of 

 animal fubftances, as the albuminous and glutinous ; fugar 

 is more nourifhing, and extratfive matter lefs fo, than any 

 other principles compofcd of carbon, hydrogen, and oxygen. 

 Certain combinations of thefe fubllances, too, may be more 

 nutritive than others. It is ftated like wife, on the au- 

 thority of fir Jofeph Banks, that the miners in Derby fhire, 

 during winter, prefer oat-cakes to wheaten bread, as they 

 iind that this kind of nourifhment enables them to fupport 

 and keep up their flrength, and perform their labour better 

 at that feafon. But that in fummer, they fay that oat -cake 

 heats them, and they then confume the finefl wheaten bread 

 they can procure. It is fuppofed, that even the fliin of the 

 kernel of oats has probably a nouriihing power, and is ren- 

 dered partly foluble in the flomach with the ftarch and 

 gluten. It is noticed, that in mofl countries of Europe, 

 except Britain, and in Arabia, horfes are fed with barley 

 mixed with chopped flraw ; and that the ftraw in this ftate 

 feems to aft the fame part as the huflc of the oat. Hard 

 thin-dcinned wheats are preferred in fome parts to thofe of 

 the foft thick-fkinned kinds, as containing a larger quan- 

 tity of gluten and nutritive matter. See Wheat. 



In regard to vegetables of the grafs kind, the only fub- 

 ftances which have been detefted in the foluble matters pro- 

 cured from them, are mucilage, fugar, bitter extract, a fub- 

 ftance analogous to albumen, and different faline matters ; 

 with feeble indications of the tanning principle in fome pro- 

 dufts from after-math crops. The albumen, fugar, and 

 mucilage, probably, it is thought, when cattle feed on grafs 

 or hay, are, for the moft part, retained in the body of the 

 animal ; and the bitter principle, extraft, faline matter, and 

 tannin, when any esifts, are probably in common voided in 

 the dung, with the woody fibre. From the great fimilarity 

 of the extraftive matter procured from the frefh dung of 

 cows, to that exifting in the foluble produfts from graffes, 

 and fome other fafts of the fame nature, it appears probable, 

 it is faid, that the bitter extraft, though foluble m a large 

 quantity of water, is very little nutritive ; but probably 

 ferves the purpofe of preventing, to a certain extent, the 

 fermentation of the other vegetable matters, or in modifying 

 or affilting the funftion of digeifion, and may thus be of con- 

 fiderable ufe in forming a conftituent part of the food of 

 cattle. A fmall quantity of bitter extraft and fahne 

 matter is probably all that is needed, and beyond this 

 quantity, the foluble matters mult be more nutritive in pro- 

 portion as they contain more albumen, fugar, and mucilage, 

 and lefs fo in proportion as they contain other fublf ances. 



In comparing the compofition of the foluble products 

 afforded by different crops from the fame grafs, it was con- 

 ilantly found, that the largeft quantity of truly nutritive 

 matter, was in the crop cut when the feed was ripe, and 

 leaft bitter extraft and faline matter ; moft extraft and faline 

 matter in the autumnal crop ; and moft faccharine matter, 

 in proportion to the other conftituent parts, in the crop cut 

 at the time of flowering. It is fuppofed that the greater 

 proportion of leaves in the fpring, and particularly in the late 

 aut\imnal crop, accounts for the difference in quantity of 

 extraft ; and the inferiority of the comparative quantity of 

 fugar in the fummer crop, probably depends upon the 

 agency of light, which always tends in plants to convert 

 faccharine matter into mucila;re or ftarch. 



No differences have been found in the nutritive produce 

 of the crops of different graffes cut at the fame feafon, 

 which could render it poffible to eftablidi a fcale of their nu- 

 tritive powers, but probably the foluble matters of the after- 

 math crop are always from oue-fixth to one-third lefs nutri- 

 tive than thofe from the flower or feed crop. In this crop, 

 the extraftive and faline matters are certainly ufually in ex- 

 cefs ; but the after-math hay, mixed with fummer hay, par- 

 ticularly that in which the fox-tail and foft graffes arc 

 abundant, would, it is thought, produce an excellent food 

 or fodder. 



In the clovers, the foluble matter from the Dutch clover 

 is faid to contain moft mucilage, and moft matter analogous 

 to albumen : all the clovers contain more bitter extraft and 

 faline matter than the common proper graffes. When pure 

 clover is to be mixed as fodder, it fhould, it is faid, be with 

 fummer hay, rather than after-math hay. 



Other obfervations on this interefting fubjeft may be feen 

 in the appendix to the above work. 



In cultivation, much ufe and advantage may, in many 

 cafes, be derived from changing the natural habits of vege- 

 tables, by fowing the feeds of them or planting them at 

 unufual feafons, by placing them in more dry and warm, or 

 more cold and moift fituations, and by altering the time of 

 their flowering, or the length of their duration, by cutting 

 parts of them, or in other ways ; as by fuch means fome of 

 them, though annual in their nature, may be made to lalt 

 and afford crops for two or for feveral years. Othei-s may 

 furnilh two or three green crops the fame feafon, and an 

 early one in the fucceeding ; and fo on in a variety of iu- 

 ftances in the garden as well as in the field. 



Vegetables, Injuries or DeftruHion of Parts of, the 

 affedtions and mifchiefs which are produced in them by 

 different caufes, as thofe of froft, lightning, infefts, and 

 fome others. It is well known, that trees of the apple 

 and fome other kinds, in field fruit-grounds, orchards, and 

 gardens, have their buds, bloffoms, and other parts, often 

 affefted or deftroyed by a fort of blight or canker induced 

 by fuch caufes ; in confequence of which there are great 

 failures in the crops of them. The mifchievous effefts of 

 froft in this way may frequently be clearly traced, though 

 they are feldom greatly injurious, when it is of the di-y kind, 

 unlefs it be very fevere ; but moll certainly fo, when it fuc- 

 ceeds to large falls of rain. Sudden tranfitions from heat 

 to cold are hurtful to vegetables : by warmth the veffels of 

 them are expanded, and their juices flow freely : a fudden 

 apphcation of cold caufes a fudden contraftion of their 

 parts, without a proportionate diminution of the fluids which 

 they contain, which being thus unnaturally checked in their 

 current, become ftagnant and difeafed. Rain is congenial to 

 the growth of vegetables ; and while Nature difpofes them to 

 open all their pores, by which its influence can be received, 

 when overtaken by froft in fuch a fituation, the confequence 

 mull be injurious or fatal. It has'been faid by aphilofophi- 

 cal writer, in fpeaking of the aftion of cold or froft, that 

 befides its oppofition to the adequate fluidity of the vegetable 

 juices, it mufl be unfriendly to the animation of the folids, 

 caufmg either local canker, or death of the whole vegetable. 

 That when the vegetable fluids are chilled, and converted 

 into ice, their bulk is vaftly enlarged, and this enlargement 

 fometimes takes place with fuch extreme violence as to rend 

 them in pieces. In this way, froft, it is thought, deftroys 

 thofe parts of vegetables whicli are moft fucculent, particu- 

 larly in that form of it which is called hoar-froft, or rime, fo 

 common in the fpring feafon. The moifture of tog too is 

 faid to be equally mifchievous, as far as it extends. Tlius, 

 in a fruit diflrift, in one night at this feafon, a moft promif- 



8 ing 



