DEFECTS IN TIMBEE AND GENERAL NOTES 295 
it very often is not, its condition may become worse on the 
voyage, it sweats and " blueing " occm's, and few would take 
" blue " deals except for the commonest purposes. 
It is not easy to detect sap in certain conditions of some 
of the whitewoods, as the colour of all the timber is much 
the same, although the sap has generally a dirtier tinge ; 
looking at a pile of round Swedish or Russian redwood 
logs we see the ring of lighter coloured sap about an inch 
thick distinctly marked from the reddish tinged heartwood 
(Fig. 37) ; but when the timber is squared and a good deal 
of the sap is cut off in the process the difficulty is increased, 
particularly so in the case of 
whitewood, as the sap is then only 
found at the edges and partly on 
the sides. Sap is almost invariably 
found on the edges even if absent 
from the sides. 
Sapwood is not so objection- 
able where the timber has to be 
creosoted, as any one looking at a 
pile of telegraph poles (Fig. 37) Fig. 51. 
will notice the complete ring of 
sapwood encircling the log, yet the long hfe of telegraph 
poles proves this not to be deleterious.^ 
The presence of sap in commercial timber is due to the 
same cause as wany edges, viz., the desire of the timber con- 
verter to get as much timber as possible out of the tree. 
" Wany timber " is the expression used for logs the edges 
of which are not sharp. Some timber is imported " wany," 
but much of the " square " timber has wanes on some parts 
1 As a rule creosote does not enter mucli into the heartwood, and 
the presence of a ring of sapwood in timber to be creosoted ensures its 
perfect preservation. In the case of street paving, however, it is possible 
that the sappy portion might not wear so well as the rest. 
