TRENCHING AND SUBSOILING 



Figf. 22 Beauquesne's Steam Winding Drum 



carrying a belt-pulley P. For shifting from one place to 

 another, the machine may be mounted on wheels. When 

 working, the wheels are removed, and the machine buried 

 level with the bottom flange of the drum. The portable 

 engine is fixed at a suitable distance, its pulley connected to- 

 the pulley of the drum by a belt. 



Working. The winding drum and the portable engine 

 are usually installed in the middle of the headland. At one 

 extremity of this headland a fixed pulley is anchored, the 

 same as is used for the horse-gin. The drum of the capstan 

 being disengaged, the cable is unwound, passed over the fixed 

 pulley, and fastened to the plough, which is taken to the 

 starting point. The portable engine is then started, the 

 pinions thrown into gear, and the plough hauled. When it 

 reaches the fixed pulley, the plough is thrown out of gear to 

 lift it out of the ground, and is stopped by throwing the 

 drum out of gear. The plough, placed on a trolley, is taken 

 back to the starting point by a horse or pair of bullocks ; 

 meanwhile the fixed pulley is displaced to an extent equal to 

 the width of the furrow. 



If the top pinion is thrown into gear, the drum revolves 

 with greater speed, the plough travels quicker, but the 

 traction decreases. If, on the contrary, the bottom pinion 

 is thrown into gear, the speed diminishes while the traction 

 increases. If the engine is powerful enough, the top pinion 

 should be used. If not, the lower one. 



We must notice that the engine does not work while the 

 plough is taken back. This time is used by the engine- 

 driver to raise the steam pressure, which, if the engine is 

 not strong enough, might have diminished. One can there- 

 fore use a relatively small power engine, which would be 

 insufficient if continuous work was required from it. 



