RATE OF COMPOUND INTEREST 241 



cent, the following rates of interest will be yielded, varying 

 according to the original value of the land : 



If the land be Eate of compound interest 



worth yielded will be 



i * 5& per cent. 



5 4* 



Rotation, 70 years -j *g 4 



22 3f !', 



3 2 3i 



* Though good land will not be sold for such a sum, yet the soil value of land 

 from which a crop of timber has been cleared can not for forestry investigations be 

 put at a higher value, for generally it would cost 20 to ^30 to stub up the roots 

 and convert it into agricultural land, and unless it were replanted it would only be 

 worth about gd. to is. per acre per annum for rough shooting, unless indeed it 

 had some other special value. 



In the above case, if the rotation had been prolonged to 100 

 years, when, at the 75th year, thinnings to the value of 16 

 might have been cut, and a final yield of 3800 cubic feet (over 

 6 inches quarter girth) attained, and worth, at is. a cubic foot, 

 1 90, the rates of interest yielded would have been as follows : 



If the land be Kate of compound interest 



worth yielded will be 



per cent. 

 5 

 Rotation, 100 years { 



18 08 



22 3t 



3 2 3 



If, on the other hand, the Larch were to be grown on a short 

 rotation of (say) 38 years for pit props, the results would be 

 much better. The thinnings would be rather heavier, so as 

 to encourage an early girth increment, and the following 

 might be expected, on the same quality land : 



Value of thinnings at the I2th year = 1. 

 1 8th = 7- 



2 5th = 7- , 

 3ist 7- 



Final crop at the 38th year worth standing (say) 50. 



These results would yield the following rates of interest : 



If the land be Rate of compound interest 



worth yielded will be 



f \ 6 per cent. 



5 5 



Rotation, 38 years \ 12 4i 



I '* 2! " 



