CUP-SHAKE. 



about a foot to two or three yards. We have thus ex- 

 ternal evidence of the presence of the star-shake in this 

 extreme case while the tree is yet standing. We can, 

 therefore, from this alone, estimate its value, and prove 

 the correctness of our opinion of it after the tree has 

 been felled. No one, I imagine, experienced in timber- 

 surveying, would, with the bulging rib in view, care to 

 examine either the top or butt end of the log to satisfy 

 himself of the presence of the star-shake ; the guide is 

 so absolutely certain that we need not fear to trust to it. 



FIG. I2a. 



My experience will not enable me to account for the 

 star-shake, and I do not remember to have seen any 

 reasonable explanation given in any work respecting it. 

 I may state, however, that it is more frequent in trees 

 which have been grown upon either a sandy or a rocky 

 soil, than in those which were grown upon loam or stiff 

 clay. 



The cup-shake (Figs. 12 a and b). This shake, which 

 is most frequently met with near the roots of trees, 

 consists of a cavity or separation of two of the con- 



