Engineering Wonders of the World
Volume III

290 ENGINEERING WONDERS OF THE WORLD. move the ground to much greater depths—a yard or more if required—than is possible where animal draught only is Advantages employed, Land which has of Deep pjøugji j jig- boon cultivated tor sovorcil years by animal power develops, in many cases, a hard stratum a few inches below the surface as the result of constant ordinary cable ploughing are compound, have steam - jacketed cylinders, a two-speed travelling gear, and, if re- quired, two speeds on the Ploughing ploughing gear They can be adapted to burn oil, fuel, or straw in countries where these fuels are more economical or more easily obtained than coal. The winding FUNT PLOUGHING TACKLE AT WORK. (Photo, Messrs. John Fowler and Company.) Where drainage or irrigation canals can be made to serve as headlands, ploughing engines are sometimes carried in suitable punts. trampling. It is estimated that horses make a footmark on every square foot of land turned up by them. The hard “ pan ” thus created prevents roots penetrating to the subsoil, and also holds up surface water in wet weather. Deep ploughing, conducted at high speed, pulverises the land, opens up the subsoil, and allows both roots and moisture to find their way downwards easily. In the case of a long drought, deeply ploughed ground acts as a natural reservoir, and supplies the growing plants above with moisture long after shallow ploughed ground would have been parched up. Th© most highly developed engines used for drum is usually carried under the boiler on a vertical axis ; for special purposes it is set vertically at the side, as shown in one of our illustrations. In addition to its agricultural duties, the ploughing engine serves as an or- dinary tractor, and to work threshing, chaff- cutting, and other machines. Coming now to the implements required for cultivation, we may begin with the ploughs. These can be classified under two headings— the balance * and the turn-round. * Despite its name, Messrs. Fowler’s balance plough is fitted with a gear which automatically moves the carriage for- ward of the centre of gravity, whichever way the plough may be travelling, so as to concentrate more than half the weight on the shares in work and prevent any tendency to jump.