. Elementi di scientifico e agricoltura pratica : O, l'applicazione della biologia e geologia, e della chimica per agricoltura e orticoltura. rform. Si sarà visto da ispezione di questa figura,che l'acqua che cade sulla corona del crinale h h willpass off verso il basso su entrambi i lati nello stesso modo in cui lo fa whenit cade sul tetto di una casa e stabilirsi in thesub-suolo, se porosi, o nei solchi di un c tra le creste. Se il terreno ha una superficie irregolare e l'acqua accumu-tardive in cave, un drain aperto è il solo efficace ri-medy. Ma nei casi in cui la superficie è di livello

• Collaboratore: The Reading Room / Alamy Foto Stock
• ID dell’immagine: 2AFT7AP
• Dimensioni dei file: 7,2 MB (423,2 KB Download compresso)
• Liberatorie: Modello - no | Proprietà - no
• Dimensioni: 1861 x 1343 px | 31,5 x 22,7 cm | 12,4 x 9 inches | 150dpi

Altre informazioni

Questa foto è un'immagine di pubblico dominio, il che significa che il copyright è scaduto o che il titolare del copyright ha rinunciato a tale diritto. Alamy addebita un costo per l'accesso alla copia ad alta risoluzione dell'immagine.

Questa immagine potrebbe avere delle imperfezioni perché è storica o di reportage.

. Elements of scientific and practical agriculture : or, The application of biology, geology, and chemistry to agriculture and horticulture. rform. It will be seen by inspection of this figure, that the water as it falls upon the crown of the ridge h h willpass off down both sides in the same way that it does whenit falls upon the roof of a house, and either settle into thesub-soil, if porous, or into the furrows a c between the ridges. If the soil has an uneven surface and the water accumu-lates in the hollows, an open drain is the only effectual re-medy. But in cases where the surface is level and the sub-soilhard and retentive, resort must be had, 2. To draining the soil This is effected by penetrating thesub-soil so as to form a passage for the water to pass off fromthe field, or a reservoir into which it may ooze from the sod. The drains by which this is effected may be either openor covered. The latter, or underground drains, are the BY DRAINING. CONSTRUCTION OF DRAINS. 257 cheapest, most durable and most effectual; for, aside from theirconvenience, a considerable quantity of land is saved for cul-tivation. (Fig. 15.). Before constructing a drain for this purpose, it is neces-sary to examine the land, and ascertain where the springsare. Most cases of surface-draining refer to swamps, orlow lands. Suppose BOD (Fig. 15) is a swamp, or lowground in which the water collects, either from the highlands, or from springs in the margin B D, or anywhere inthe centre of the meadow. The first thing to be done, inthis case, is to make an outlet for conducting the water awayto some stream as at O S. The second is to run a drainthrough the centre from Cto O, and all around the marginB D, to cut off the springs, and to conduct the water into themain drain A, or outlet. In each case these drains shouldbe sunk into the sub-soil, and if much water flow in themthey should be open, especially the central drain. In thisway the swamp can be rendered perfectly dry and capable ofbeing

Parole chiave associate all'immagine

• bookcentury1800
• bookdecade1840
• booksubjectagriculture
• bookyear