Fig. 2. Represents the right side of the plough, with all the parts that can be seen on this side, in which TV is the mouldy board, &c.
Fig. 3. Represents the under part of the plough, in which may be seen the shape and size of the share, and how it is fixed on the sheath and mouldy board, plough sole, and mouldy board, &c. as they appear below, or looking on the under side of the plough.
Fig. 4. Represents the upper view of the plough, or as she tills, in which may be seen the several parts, as they appear on this side, the bridle NP, mouldy board TV, &c. in their several shapes and sizes.
Fig. 6. a, The upper part of the stock or share.
b, The sock, as it is fixed on the end of the sheath and mouldy board.
c, The perspective of the bridle.
Fig. 7. Represents the higher part of the plough, it; which are seen the two stilts El', lin.der part or On mouldy hoard TV, and a piece ul wood in place of the head LM, in their prop( r shapes and sizes.
The whole of this plough ought to he made of ash of elm ; the irons should be steel•d and well tempertel ; and that part of the plough which is under ground in tilling ought to be covered with plates or iron.
The difference between this and the common ploughs, seems to consist in the bridle at the end of the brain, by which the ploughman can give the plough more of less land by the notches at N in Fig. 3 and 4, or mak( her plough deeper or shallower by the holes at P iii Fig. 1. and 2. ; in the coulter and share, which are made and set so as to cut of the new furrow without tearing ; and, in the mould-board, which is of such a fashion us first to raise a little, and then gradually turn over the new-cut furrow with the least resistance : and the advan tage attending such ploughs must be an easy draught ; so that two horses are able to do the work of four, which is found by experience to be the case on all ara ble grounds.
We have been thus particular in our accounts of the Rotherham plough, because its construction was the first attempt to depart from the ancient system of work ing the soil, at a heavy expense, with large and cumber some implements. But though the Rotherham plough was brought to Scotland only ten years posterior to the date of Mr Foljambe's patent in England, yet the use of it was adopted by very few people, till 1764, when it underwent several alterations, and gradually came into general practice. The first alterations were not of much
importance ; in fact, the chief one consisted in using a chain, which at the best answered no purpose unless to strengthen the beam at a place where it seldom was damaged. The head, and every part of the implement, except the chain, muzzle, sock, and coulter, were of wood, with the addition of a covering of thin plated iron upon the mould-board, to prevent it from wearing. The mould-board, from being straight, gradually assumed a curved figure, till finally that important member of the implement was made of cast metal, prepared at founde ries upon principles which, from practice, may be pro nounced correctly adjusted. The head, which was formerly constructed of wood, and constantly needing repair, is now also made of iron ; hence the share, or sock, is kept steadily fixed when at work, which was not the case when wooden heads were used.
These improvements were chiefly devised, and, in the first instance, executed by Mr James Small, a per son to whom the agricultural interest of the country is under great obligations ; he being, with the exceptions of Messrs Lummis and Dalziel, the first artisan who attempted to improve ploughs in Scotland upon mathe matical principles. The sock, or share, is made with a fin, or feather, whereby the firm earth at the bottom of the furrow is cut more completely than was practi cable by the sock of the old ploughs, which acted more in the way of mining and forcing-, than cutting and re moving the earth with facility or ease ; and the mould board being of cast metal, may be set wider or closer according to the nature of the soil on which the plough is to be used, or the height of the ridges that are to be. ploughed. This implement is, therefore, the best con. st•ucted swing plough in the island ; and by means of it a man and two horses will, with all ease, plough au English acre per day, except in particular seasons, when the soil from drought has beCOMC hard and obsti nate. \Ve have often seen a Scotch acre (one lifth larger than English measure) ploughed in two jour neys, or nine hours' work ; but this was either when the land was seed furrowed, or with a soil of a loose and triable nature.