414 
that the water gradually dried out from within the cells, but, 
so long as there was any free water at all within the cells, the 
walls remained satutated and no change consequently took 
place in the dimensions of the block. The stage shown by the 
curves of fig. 3 where the insignis blocks show no contraction 
at all as they dry out from about 140 to about 50 per cent. 
of moisture represents the phase therefore when the free water 
is drying out from within the cells, but the cell walls are still 
IN 
A 
ug 
m] 
S SE Q 
sg 
i Q 
419 
S 
n 
Sr 
Lu 
tw 
2t | 
ji 
ng 
PERCENTAGE OF MOISTURE ON DRY WOO. 
[6] 6C BO JOD LO MO W 
Fig. 4. 
Showing expansion with moisture of Pinus maritima. 
À, sapwood parallel to rings. B, sapwood perpendicular to 
rings. C, heartwood. ‘ 
saturated. Beyond that, when the cells have lost all ther 
free water, moisture is then given out by the cell walls LE 
| contraction begins to take place, this contraction being mu? 
| more marked in the direction parallel to the rings than in the 
| .. radial direction. 
|. The blocks from which the curves of fig. 3 were drawn 
E. were cut from near the centre of the tree and contained 4 
