Page:Encyclopædia Britannica, first edition - Volume I, A-B.pdf/82

 A G II I C U L T U R E. is made to turn inwards; and the fore-part of it, which eafy for the ploughman to keep the ridges ftraight, which is ftraight below, is more and more curved the further it is difficult to do without them. The difadvantages attending a wheeled plough are up it comes, refembling the bow of a fhip/j If one mold-board be preferable to another, it mufi nearly equal to its advantages. It has too much-mabe either becaufe it throws the earth of the furrow more chinery, which is an inconvenience in any inftrurnent... It properly, or makes the plough more eafily drawn. Now, is improper for ploughing ridges acrofs. It is'-uifo very the ufe of the mold-board is to raife the earth, turn it inconvenient for ploughing narrow ridges; for it- Wnrft over, and, if it be taken off narrow, to ftiift it a little be frequently altered in ploughing out a ridge. - The to the right hand. The common mold-board, when wheel that goes in the furrow being higher than the oright made, performs all thefe operations gradually. But ther, when both wheels are going upon the furfircc, the the curved- mold-board, as it is call out above in the beam muft be changed from its ordinary pofiticn, and fore-part, prevents the furrow from rifing, and turns it placed in fuch a manner as to keep th§ plough even, and over fuddenly. In land that eafily breaks in pieces, the to make it go a little deeper than ordinary. When a common mold-board has the advantage, becaufe it raifes furrow is made for the wheel to go in, the'be am muft when the the earth of the furrow higher than the other, and leaves be altered again to its ordinary pofition ; and it more loofe and open. But the curved mold-board ridge is near finilhed, fo that both wheels- are going irj is preferable in land that is not eafily broke, for, by furrows, the pofition of the beam muft be changed, to turning over the earth fuddenly, it is apter to tear it keep the plough even, and to prevent it from going too .deep. afunder. The plough is more eafily drawn by the common mold-board, as it has lefs fridion than the curved one. Of the Four-coultered Plinigh. this plough is faid to be ufed with fucOf the Plough with the feathered Sock. cefs.In England, But after repeated trials by thofe who attempted The difference between the feathered and the com- to ufe it in Scotland, they have been obliged to give mon fock will be bell underftood by comparing their fi- it up. gures. Fig. 14. is the common fock, and fig. 15, the So many coulters in the ground at once muft meet with many obftacles, which will give different direftions feathered one. From the conftrudion of the feathered fock, it is ob- to the plough, according to the different parts of the vious, that it mufi meet with greater refiftance than the coulters to which the refiftance is applied. Befides, it is common fock. However, when the plough takes off the difficult to place the planes of the coulters exadlly paralearth of the furrow broader than that part of the fock lel to each other; and if this be not done, they will be which goes upon the head, it is more eafilydrawn than the continually a(Sling upon the plough in different directions. plough wjth the common fock; for the earth whiter the When this plough is employed for breaking up grafscommon fock leaves to be opened by the wreft, is more grounds, which is the chief defign of it, the oblique poof the coulters is apt to raife the turf in fuch q. eafi’.y opened by the feather of the other fock. In lea, fition the feathered fock makes the plough go more eafily, be- manner as to intangle it betwixt them, and thereby encaufe the roots of the grafs, which go beyond the reach tirely ftop the plough. This plough ftiould always be made with wheels for of the plough, are more eafily cut by the feather than regulating its direction; the planes of the coulters flioukl they can be torn afunder by the common fock. The feathered fock is alfo of great ufe in cutting and defiroying be exactly parallel to each other: The firft coulter muft root-weeds. The common fock, however, anfwers much be fet almoft perpendicular, and (hot!Id not go above two inches deep; the fecond ftiduld Hope a little, and go better in ftrong land. It is proper here to add, that in fitting the feathered fomewhat deeper than the firft, and fo on to the laft. fock to the head, the point of it Ihould be turned a little Soft meadow-land, free from ftones^ is beft adapted to the nature of this plough. from the land, or a little to the right hand. Of the Iron Plough. Of the Wheeled Plough. This plough is formed upon the model of the old Scots Th e Scots wheeled plough is formed by adding wheels plough; only the feveral parts of it are fliorter, and'the to the old Scots plough, and giving it a curved moldhead and fock are of one piece like the Englifh ploughboard, or feathered fock, according to the inclination of .ftiare. the farmer. The advantage or disadvantage of the ITiis plough is lighter, and cenfequently more eafily wheels is therefore the only thing to be ccnfidered in drawn than any other plough ufed in Scotland ; and, as this place. the friction is alfo diminiffied. Neither is The following are the principal advantages of wheel's it is {hotter, fo apt to ftick to it, and clog it while going. to a plough of this kind. Wheels regulate the plough; the earth thefe are only feeming advantages ; for thelightnefs tlpey make it go to a certain depth, take off the earth of But the furrow of a determinate breadth, and make the and ftiortnefs of it render it extremely fubjeCt to change -Soft plough very eafy to manage. Wheels likewife make it its direction upon meeting with the ieaft obftruCtion. land. S6