chance to dry out before or after it was placed
in use. The wood which was exposed to decaying influences was
generally selected from those woods which, whatever their other
qualities might be, would resist decay longest.

To-day conditions have changed, so that wood can no longer be used to
the same extent as in former years. Inferior woods with less lasting
qualities have been pressed into service. Although haphazard methods
of cutting and subsequent use are still much in vogue, there are many
signs that both lumbermen and consumers are awakening to the fact that
such carelessness and wasteful methods of handling wood will no longer
do, and must give way to more exact and economical methods. The reason
why many manufacturers and consumers of wood are still using the older
methods is perhaps because of long custom, and because they have not
yet learned that, though the saving to be obtained by the application
of good methods has at all times been appreciable, now, when wood is
more valuable, a much greater saving is possible. The increased cost
of applying economical methods is really very slight, and is many
times exceeded by the value of the increased service which can be
secured through its use.

Manner of Evaporation of Water

The evaporation of water from wood takes place largely through the
ends, _i.e._, in the direction of the longitudinal axis of the wood
fibres. The evaporation from the other surfaces takes place very
slowly out of doors, and with greater rapidity in a dry kiln. The rate
of evaporation differs both with the kind of timber and its shape;
that is, thin material will dry more rapidly than heavier stock.
Sapwood dries faster than heartwood, and pine more rapidly than oak or
other hardwoods.

Tests made show little difference in the rate of evaporation in sawn
and hewn stock, the results, however, not being conclusive. Air-drying
out of doors takes from two months to a year, the time depending on
the kind of timber, its thickness, and the climatic conditions. After
wood has reached an air-dry condition it absorbs water in small
quantities after a rain or during damp weather, much of which is
immediately lost again when a few warm, dry days follow. In this way
wood exposed to the weather will continue to absorb water and lose it
for indefinite periods.

When soaked in water, seasoned woods absorb water rapidly. This at
first enters into the wood through the cell walls; w