146 TIMBER AND TIMBER TREES. [cHAP. 
shrinks very little, it rarely warps, and stands exposure 
to the weather a long time without opening with surface 
shakes, or sustaining any apparent damage. 
African timber, possessing, as it does, so many 
good properties, is employed in ship-building for 
beams, keelsons, riding bitts, stanchions, &c., and in 
a variety of ways; but in civil architecture, and in the 
domestic arts, it is only sparingly used, on account of 
its weight. 
This timber is brought upon the market in very 
roughly-hewn logs, intended, no doubt, to be square, 
but varying considerably from that form, and taking, 
generally, the most irregular shapes (Fig. 23). Some- 
SQ _ccan 
mA AY 
times they are angular, at other times they have a thick 
and a thin edge, resembling, in some degree, a “ feather- 
edge” board ; again, we find they are neither tapered to 
the natural growth of the tree, nor made parallel longi- 
tudinally, but vary in thickness in that direction, leading 
to a most serious waste of the raw material in the neglect 
to preserve the fullest-sized square log obtainable from 
the tree. ; 
It will naturally be inferred that, being thus awk- 
wardly shaped, it is the most difficult of all timber to 
measure correctly, 
