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THE COMPLETE GRAZIER. 



BOOK VIII. 



which has an acute point, suitable for hard land ; another form is in great 

 favour with market-gardeners and other cultivators of lighter soils, as it is 

 light in construction, and is fitted with a chisel-pointed share, which 

 makes it run steadily. Both are provided with a spreader behind the 

 mould-board, to level down the soil when it is turned, but this can be 

 removed if desired. These ploughs will turn a furrow fourteen inches in 

 breadth, and nine inches deep, if required ; and r,t any depth they need 

 no more than two-thirds of the labour required by the ordinary ploughs, 

 working at a corresponding depth. A narrow furrow is essential on 

 almost all soils when the common plough is used, but the looser nature 

 of the furrow turned by this, caused by its falling over without compres- 

 sion, makes the narrow furrow no longer necessary, whilst a broad furrow 

 is advantageous. 



Fig. 262. Hornsby's Double Furrow Plough, with Sub-soiling Attachments. 



These ploughs may be made in the multiple form, and it is worthy of 

 note that the great plough-making firms have made the bodies so that 

 they can be fitted to the beams of their ordinary ploughs with the greatest 

 ease ; hence there is every inducement to farmers to adopt them. 



When land has been ploughed at one and the same depth for a con- 

 siderable time, and on account also of other causes, the subsoil becomes 

 very hard, forming what is known as a pan. This prevents the water 

 from draining through, and thus injures the crops ; it is therefore neces- 

 sary to break it. But as subsoils often contain injurious matter, they 

 must not be brought to the surface, so that the ordinary plough is use- 

 less, and a special implement the subsoil plough is required. 



Fig. 262 shows a double-furrow plough in which one of the mould-boards 

 has been replaced by a subsoiler. It will be seen that the subsoiler is work- 

 ing in the horse- walk, while the mould-board is turning a furrow on to 

 the freshly-stirred subsoil ; if the draught is too heavy, a single-beam sub- 

 soiler can be used, in which case it will have to follow the plough directly. 



