American citizen. [volume] (Canton, Miss.) 1864-1890, 1875-03-06
The Preservation Of Timber.


the upper portion of the unseasoneC
wood, the fermentation of the sap
brought about by the influence OF
warmth combined with certain amount
of moisture, will produce dry-rot. Al
the waterline, and between high and low
water mark, there will probably appear
wet-rot; while under water, and perhaps
above, also, the attack of insects may be
looked for.
Between the ravages of dry-rot, wet
rot and insects vast quantities of valu-
able timber are ruthiessly sacrificed
which might be saved by the slightest
foresight and diligence on the part of
the woodsman and builder.
Dry-rot is the most insidiouS of these
destroyers of timber, because it works
in the dark. 1t commences in the in
terror of the wood and goes on upper
ceived and unsupported, reducing the
firm mass to powder, while the exterior
remains till the last moment unaltered.
Sometimes, while care has been taken to
protect a piece of timber from wet-rot
by a coating of waterproof substance on
the outside, this very precaution has
by stopping the circulation of air-in
duced the far more rapid and destructive
dry-rot in the interior.
1t is important that timber should be
surrounded by freely-circulating air.
The presence of foul or dead air acts
upon it much as it does upon living
body, and when, in a badly-ventilated
place, there are fcrmenting sap and
moisture contained in the wood, a cor
rosive liquid or gas is formed, which
soon destroys the whole interior. The
fermenting sap gives nourishment for
fungus, which usually-not always-ac-
Companies dry-rot. The fungus proba-
bly, grows from minute seed of the para
site which enters the fiber while the tree
is growing-perhaps absorbed by the
sap through the leaveS-or it may attach
itself after the tree Is felled. Dry-rot is,
of course, rarely found in timber which
has been cut at the proper time of the
year and properly seasoned.
In ancient times trees used to be
girdled, and were cut down when dead
after the sap was supposed to have run
out. The present custom is to fell the
trees at the season when the sap is in the
roots, early in the spring. Though il
would be easy to decide by experiment
which is the best month in the year for
cutting timber, very few such expert
ments are ON record, and those have been
little discussed in print. An article pub
Hshed some years ago in Stlinian's Jour
nal gives some interesting information
regarding vessel built in 1911 by a Mr.
Rainey. The timber was cut in Deem
Der, 1910, sufficient white oak and chest
nut being provided for the ship, it was
thought; but as the work progressed il
was found necessary to cut several more
white OAK trees in May, 1911, to supply
the after part of the plank sheers.
Four years afterward the ship was
found to be much. decayed, but the upper
part, which had been built of timber cut
in the spring, was perfectly sound. This
led Mr.. Rainey to think that the theory
generally received might be erroneous,
and that the sap is in the heart-wood in
stead of in the roots of the tree during
the winter. To test this, he cut some Sec
tions of oak in midsummer, and others
in winter, which he subjected to great
heat. In those cut in summer he observed
a wet ring around the exterior of the
wood, while the heartwood was com
paratively dry. The slabs cut in winter
gave exactly the opposite results; the
wet circle being in the center, and very
little steam and moisture issuing from
the outer rings. This would indicate
that the sap does not pass the winter in
the roots, and on this theory it is better
to gather timber in the late spring or au-
tumn months. Oaks are often felled at
that time in England for the sake of the
bark, but the wood does not command
the ordinary market price, showing that
there is a prejudice in favor of winter
felled oak.
The obvious means of preventing de-
cay is by removing the soluble matter
and the water from the wood by drying
or otherwise.
Green wood contains from IS to 40
per cent. of water to be evaporated.
Only time can accomplish this per-
fectly, though the application of
heat assists very much and if tine vege-
table albumen is first washed out of the
wood by cold water and thorough
steam drying follows we shall obtain a
material which is almost imperishable
under ordinary exposure. Borax is often
used for dissolving the albumen and is
found very efficacious. Corrosive subli-
mate, applied as solution, one ounce to
gallon of water, laid on while hot, is a
good antidote. 1t is now known as
kyan's process. The timber is immersed
in the solution in a wooden tank con-
tanning one pound of the sublimate to
ten gallons of water. \ mixture
of sulphate of copper and sulphuric
acid in the proportion of one pound of
each to six gallons of water has also
been found to preserve timber. Sui
plate of copper should first be dissolved
in one gallon of boiling water, and the
remainder of water and sulphuric acid
added afterward. Sir w. Burnett rec
commended soaking the wood in a solu
ton of chloride CT zinc; and solution
of bi-chloride of mercury injected into
the pores of the wood by an air-pump
has been found efficacious Timber
which has not been properly seasoned
should never be painted. 1t Is well
known that while paint and tar con-
tribute to the durability of dry timber,
4 he u e
seasoned wood. Another destructive
practice common with builders is bed
ding timbers in walls exposed to damp.
Dry lime has preservative influence
upon dry timber, and protects it also
from the attacks of insects; but quick
lime, when assisted by moisture, hastens
decomposition.
In Norway telegraph poles are preserved
from decay by introducing a solution of
sulphate of copper Immediately after the
tree is felled. Holes are bored in,o the
wood, to depth of four or six inches,
filled with the sulphate, and plugged up
with corks coated with tar The circufa-
ton OF the sap, which continues for
some time after the tree is cut down, car
ries the solution throughout the length
of the pole, and thoroughly impregnates
every pore in the most natural and sim
pie manner, greatly increasing TIE dura-
bility of the wood.
1t is well known that salt has IA great
preservative influence upon wood. The
watts and supports of salt factories have
never to be renewed; but at some of the
salt mills and mines of rock salt in
Europe the wooden timber and structures
remain to-day in as sound a condition as
when they were built, centuries ago.
The water from peatbogs has similar
effect upon wood, and a patent has been