GENERAL METHOD OF SAMPLE TREES. 



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all regularly grown woods. It follows, that the degree of 

 accuracy decreases with the increase in the number of classes, 

 which are clubbed together into a group, the least accuracy 

 being obtained by joining all classes into one group. In 

 this latter case, the method is known as " the method of the 

 arithmetical mean sample tree." 



Example. — In order to illustrate this and the methods to 

 be described hereafter, one acre of Scotch pine wood, 70 years 

 old, was measured, and twenty-four sample trees of various 

 diameters felled and measured. Only timber down to 3 in. 

 diameter at the small end has been included in the account. 

 The wood is situated at Caesar's Camp, on gravelly sand with 

 a fair layer of humus, showing a yield capacity of about 

 middling quality. The following list shows the dimensions 

 and the volume of the sample trees : — • 



List of Twenty-Four Sample Trees. 



The subjoined statement illustrates the procedure, which has 

 just been described. 



E 2 



