10 



do. 



21 3 



5 



12 



do. 



24 



4 



16 



do. 



26 10 



8 



20 



do. 



27 9 



4 



METHOD OF VALUING GROWING TIMBER. 301 



V Whatever the lengths of the boles of trees increasing as 

 ahove may be, the increase is 5 per cent per annnm one year 

 after their girt in the middle is 10 inches, but not longer. 



But supposing that these trees have grown to 60 years of ^"'^ ^^^* 

 age, and increased as above-mentioned, their girt and con- 

 tents at that age would be as under, viz. 



Contents. 



Ft. in. p. 

 Trees with 16 ft. boles, 13 inches girt at 8 ft. high, is 9 4 

 Do. 20 do. 12| do. 



Do. 24 do. 12 do. 



Do. 32 do. 11 do. 



Do. 40 do. 10 do. 



This table shows, that the advantage to be gained by Boles of 32 

 pruning trees higher thau 32 feet is not an object worthy ^^et, 

 ©f consideration, if the trees are to be cut down at the age 

 of 60 years. 



And if it should be found, that, the higher a tree is 24 feet, 

 prnned, the slower it, swells in the bole, perhaps a 24 feet 

 bole may measure as much at 60 years old as a 32 feet bole. 

 If it increases half an inch in girt in the last 36 years more 

 than the 32 feet bole increases in the same time, it will very 

 nearly equal it in measure. 



A 32 feet bole with a top from 20 to 30 feet high, with and 40 feet, 

 many large lateral branches, is certainly a much finer 

 object than a forty feet bole with a top only twenty feet 

 high, with a few and small lateral branches : and at sixty- 

 years old, the former will have had to increase in the last 

 twenty-eight years only one quarter of an inch in girt, 

 more than the latter, to exceed it in measure, to say nothing 

 of the excess of timber in the larger top and branches. It 

 must, however, be remarked, that at eighty years of age, 

 the forty feet bole will exceed the thirty-two feet bole nearly 

 six feet ; and at one hundred years, thirteen feet, provided 

 it swell equally fast in thickness. But unless the trees be 

 oak, fit for the use of the navy, for which an increased 

 price can be had, I imagine few gentlemen would now 

 choose to let their trees stand to eighty years of age, when 

 the increase of their boles will not be four per cent; still 

 fewer would let them stand to one hundred, when the in- 

 crease will not be three per cent per annum. 



Again 



