52 TKENCHING AND SUBSOILING 



a cog-wheel is fixed, gearing with a second pinion, keyed on 

 the shaft which carries the pulley ; this is connected by a 

 belt to the pulley of the engine. The two machines, therefore, 

 form one. The iron frame rests on rollers, rolling on rolled 

 joist girders. The tires of these rollers are perforated with 

 holes in which levers are engaged for displacing the system. 

 The axles of the rollers may move obliquely to allow the 

 system to be displaced easily on a curved or sinuous headland. 

 When the end of the block is reached, it is easy by turning 

 it at 90 to plough the headland. In this case special curved 

 rails are used. A brake to control the unwinding, and a 

 gearing lever complete the machine. The model exhibited 

 at the Perpignan Show had, in addition, an arrangement 

 allowing the plough to be hauled back to the starting point. 

 For this purpose the intermediate shaft had a small drum 

 keyed on to it, on which a thinner cable was wound. This, 

 after passing over the fixed pulley, was tied to the rear of the 

 plough. A lever threw it in or out of gear. 



Working. The working of this system is very simple ; the 

 frame carrying the engine and capstan is installed on the 

 shortest headland. The thinner cable fastened to the rear 

 of the plough hauls it to the opposite headland. When the 

 plough reaches it, the small drum is thrown out of gear ; this 

 throws the large drum into gear, and the plough is hauled. 

 When the plough reaches the system the small drum is thrown 

 into gear, hauling it back to the starting point, and so forth. 



In the meantime the system has been displaced laterally. 



The fixed pulley and the small cable runner are indispens- 

 able to guide the cable. Their anchoring, however, is simple, 

 for they have only a small effort to sustain. The pulley and 

 runner may be displaced during work without waste of time. 

 The non-ploughed headland on the engine side is 39 feet in 

 width ; on the opposite side, 10 feet. 



The plough is the same as that used with the Guyot horse- 

 gin. With an 8 H.P. engine working at 140 revolutions the 

 plough travels at a rate of 59 feet per minute. 



Three men are required for the working ; one engine- 

 driver, one to work the capstan, and another to work the 

 plough. If the small drum is used, another man is required 

 to shift the runner and the fixed pulley, in the other case a 

 horse and a boy. 



This machine works perfectly ; its management is simple, 

 and the loss of time is reduced to a minimum. Only the 



