OK SUBSOILING PLANT. 95 



3 inches per second. Lifting the plough at the end 01 

 the furrow and placing it on the sledge took from one and a 

 half to two minutes. The winding drum also served to pull 

 out stumps (2 feet to 2ft. 6in. in diameter) previously grubbed 

 round to a depth of 2ft. Sin. and a width of 2 feet, after the 

 fashion of a forest devil. 



The cost of ploughing 1 acre with a horse-gin differs in 

 each particular case. Here is, however, an example of the 

 way of calculating it : 



A horse-gin, worked by four horses, taking, as an average, 

 seven days to trench 2 J acres, the complete material costing 

 100, the annual writing off being 20 per cent, for a capital 



of 20.* 



The daily expense of the work is : 



s. d. 

 4 horses at 4s. ... ... 16 



2 bullocks at Is. 7d. ... ... 32 



2 men at 2s. 4d. ... ... 4 8 



2 boys at Is. 7d. ... ... 3 2 



Total ... ... ... 27 



That is to say, 27s. x 7 = 9 9s. per 2 acres. 



We may draw the following table by assuming a maximum 

 of 200 days' work per year : 



Cost per 2 acres. 



Number of ,.,,. 



Totals. 



* The details of this capital are as follows : 



Writing off 100 in ten years at 4 per cent. ... 8 



Wear and tear at 1 2 per cent. ... ... ... 12 



Total ... ... ... ... ... 20 



Representing in gross 20 per cent, of the capital (100). In the above we 

 do not take into consideration the interest of this capital, this latter being 

 by a contractor pre-entered to his profit ; that is to say, the difference 

 between the price tendered and the cost of the work, plus general 

 expense. 



