hen these are
soaked, the water will fill the cell lumen, so that if constantly
submerged the wood may become completely filled with water.
The following figures show the gain in weight by absorption of several
coniferous woods, air-dry at the start, expressed in per cent of the
kiln-dry weight:
ABSORPTION OF WATER BY DRY WOOD
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| White Pine | Red Cedar | Hemlock | Tamarack
---------------------------------------------------------------
Air-dried | 108 | 109 | 111 | 108
Kiln-dried | 100 | 100 | 100 | 100
In water 1 day | 135 | 120 | 133 | 129
In water 2 days | 147 | 126 | 144 | 136
In water 3 days | 154 | 132 | 149 | 142
In water 4 days | 162 | 137 | 154 | 147
In water 5 days | 165 | 140 | 158 | 150
In water 7 days | 176 | 143 | 164 | 156
In water 9 days | 179 | 147 | 168 | 157
In water 11 days | 184 | 149 | 173 | 159
In water 14 days | 187 | 150 | 176 | 159
In water 17 days | 192 | 152 | 176 | 161
In water 25 days | 198 | 155 | 180 | 161
In water 30 days | 207 | 158 | 183 | 166
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Rapidity of Evaporation
The rapidity with which water is evaporated, that is, the rate of
drying, depends on the size and shape of the piece and on the
structure of the wood. An inch board dries more than four times as
fast as a four-inch plank, and more than twenty times as fast as a
ten-inch timber. White pine dries faster than oak. A very moist piece
of pine or oak will, during one hour, lose more than four times as
much water per square inch from the cross-section, but only one half
as much from the tangential as from the radial section. In a long
timber, where the ends or cross-sections form but a small part of the
drying surface, this difference is not so evident. Nevertheless, the
ends dry and shrink first, and being opposed in this shrinkage by the
more moist adjoining parts, they check, the cracks largely
disappearing as seasoning progresses.
High temperatures are very effective in evaporating the water from
wood, no matter how humid the air,
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