FlQ. 39. Three specimens of oak grown under different conditions. 



The upper one is from a rapidlv-irnAvn tree, in the open, and at a low altitude ; 

 the wood U Teiy BtrODg, hanl, and heavy (density ()'Si>7 ), because there is a pre- 



ponderanoe of fibres in the broad rin.us. Tiie middle specimen comes from a tree 



frrowiiitf slowly in a forest at, a consiileratile altitude ; the narrow rings have too 

 UUTge a proportion of vessels, whence the \vo.n I is .-nt't (ilensity <>'t''91 ), porous, ami 

 weak. The lower section is from a tree which has }/rown very irregularly on poor 

 soil, as shown by the variable rin^s ; only the parts with l>n>ad rings are good 

 hence bad wood predominate! (density <7li'). ( Nanquette-Boppe.) 



