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 $0 A G R I C t ‘ L T U R E. manuring. The firmnefs of the furface prevents any of • which is laid from time to time upon it. This is the onthe foil from being carried off when the water is drain- ly diftinfiion betwixt out-field and in-field land. ing, and the grafs intangles the mud, <&c. and hinders The foil which contains a great proportion of loam, requires very little manure. It may be kept coriftantly in them from going along with the water. This operation Ihould be performed in the fpring. In good heart by proper tillage and good management. that feafon grafs-lands fuffer lead from being •over- The common loarny foil ‘requires manure, and no kind of manurh is improper for it; dung, however, is sowed. unqueftionably the heft. Lime, unlefs managed with care, is in danger of hurting a loamy foil by exhauftSect. Ill, Of Soils with respect to ing it. Manures. Of the Clay-Soil. Soils are very different in their natures, and compofed of Very different ingredients: Some foils contain The richeft kind of clay-foil is that which confifts of clay and loam. To difcover the nature of this foil, it more, and others lefs, of the food neceflVny for the nou- is necelfafy to know the qualities of clay. riihment of plants. It is neceflary to inquire into thefe Clay is a very folid body, and its parts adhere firmly differences, in order to difcoyer what manures are moft together: It does not eafily admit water, but is capable proper for each kind. The foils moft common in Scotland are the black of containing a great quantify, fwells but little, and does loamy, the clay, the fandy, and the moffy. Of thefe not eafily part with it. When dry. Clay- is very hard, becomes the harder the more fuddenly it is dried. there are many varieties, according to the different pro- and In the procefs of drying, it contracts unequally, and portions of that particular kind of earth from which they breaks out into rents or fiflures where the cohefion is are denominated. Some foils are even fo blended, that it is difficult to determine what kind of earth moft pre- weakeft. It ferments v/ith acids, but has no oil in its compofition. vails in them. From £ flight view of thefe qualities it appears, that a clay-foil is not fo well adapted for the nouriftiment of Of the black Loamy Soil. plants as the loamy: it is more fubjedt to receive infrom drought or rain. In a rainy feafon, as it is Pure loam feems to be nothing elfe but the earth of juries averfe to part with the water after it once admits it, the putrefied vegetables, accumulated by the fucceffive de- roots will be much weakened or deftroyed by cay of natural or artificial crops. In cultivated lands, being oflongplants in the water. On the other hand, in dung and other manure greatly increafe the quantity of a very (jry foaked feafon, it becomes fo hard, that the roots the loam. penetrate deep enough to fearch for food. The principal qualities of loam are thefe : When al- cannot obfervations are fully confirmed by experience. lowed to reft, it acquires a degree of cohefion, but ne- ForThefe well known to the hufbandman, that the prover becomes fo hard and tough as clay: When turned duceitofis clay-foils are extremely uncertain, as they are up and expofed to the air, it becomes free and open, liable be deftroyed by dry or wet feafons. Thefe foils and eafily crumbles down : When, dry, it readily admits labour-tounder difadvantage; as they repel water, water, and fwells and retains it like Ihell-marle; how- efpecially whenanother in fmall quantities, they reap no ever, it only retains a proper quantity, and allows the benefit from dewsit falls or flight {bowers. reft to run off. It alfo contains oil, fermentswith acids, The clay-foil is faid to contain vegetable food, but does and is of an abforbent nature. allow it to be eafily diffolved: and hence lime, marks, There is no foil altogether pure; but that foil which notaflies, are the moft proper manures for it, as they divide has loam in its compofition ..poffeffes in feme degree all orit into particles. . Thefe manures likewife commuthe qualities of loam; and thefe qualities are unqueftion- nicate tofmall it a greater power of abforption ; and therefore ably the moft proper for nourifhing plants. will enable it both to receive andtranfmit water more Its oils and falts afford food to the plants ; the abfor- they readily, and of courfe make it lefs fubject to be injured bent quality of which it is poffeffed, alfo attrads vegetable by weather. Clay-foils, when mixed with loam, food from the air; its friablenefs, aad fermenting with the very rich ; but, when mixed with fand or till, they ' acids, give an eafy paffage to. the roots to acquire this are are very poor. Poor clay-foils require fuch manures as food. greateft quantity of vegetable food; thereExperience, the only fare guide in fubje<fts of this containdung,the fhell-marle, fea-weed, 6c. are the belt makind, fhows that a loamy foil is inoft fruitful. Some fore lolls, when well limed or dunged, may bear as great nures for them. crops as the loamy foil; but then they require a fupply inuch fooner.. The loamy foil has likewife another adOf the Sandy Soil. vantage pver every o^her : It does not fuffer fo much There are two kinds of fand that enter into the comfrom drought or rain, as clay and fandy foils. All land called in-field land has a certain quantity of pofition of foils; .the one confifts of fmall particles of loam in. its compofition, probably owing to the dung flint, the other of broken firells. The