INSTALLATION OF TEENCHING 



INSTALLATION OF TRENCHING OR SUBSOILINO 



PLANT. 



SIMPLE-EFFECT CAPSTANS. 



The installation of such plant is to be considered according^ 

 to whether 



1st. The capstan is displacing or not; 



2nd. The hauling back of the plough takes place with a 

 special team (one horse or two bullocks), or with an addi- 

 tional mechanism on the capstan ; 



3rd. The work is done in one direction with the plough 

 turning the sod on one side only, or in both directions with 

 a turn-wrest or balance plough. 



When the capstan is displaced for each furrow the traction 

 is said to be direct. In this case (Plate I.), the 'capstan A is 

 installed on one of the headlands b 5', the cable t hauling 

 the plough C in the direction of arrow 1. At the start 

 the plough is at d\ it opens a furrow d' e' , when it reaches 

 e' the drum A is disconnected, the plough C taken back to 

 d" in the direction of arrow 2, the cable unwinding. During 

 this operation the horses rest and the capstan is moved 

 a distance equal to the width of the sod in the direction of 

 arrow 3. 



With this installation, the width of the non-ploughed 

 headland a a is reduced to 9ft. lOin., while that of the 

 headland b b' is equal to the diameter of the track m that is 

 to say, '62 feet to 38 feet. An area d d' e e smaller than 

 the block, is ploughed that way, the two headlands a of b b' 

 being ploughed in the direction of arrow 3. 



This installation, which dispenses with the fixed pulley 

 and reduces the length of the cable (as compared with other 

 systems) has the drawback of leaving on the capstan-side a 

 wide headland tramped by the horses. 



The displacement of the capstan A (Plate I.), in the 

 direction of arrow 3, may be done in two different ways ; 

 the drum is fixed to a bed-plate, fastened to a chain n g n 

 secured to two anchors N N', or may travel laterally on rails. 



