Year: 1871

As the question. has often been asked
What will preserve wood from decay l
would say that there are great many
ways, and several patents have been is
sued therefor. With but little expert.
ence extended solely to this subject, but
with somewhat careful reading from
high aud good authority. l will give the
various processes for saving timber; but
particularly the bottom timber of our
houses. As insects trouble our timber
but little, we have no difficulty with them.
What we want is protection from wet
rot, aud dry rot. They are often con-
fused with one another, but they should
be distinguished in the following:


Wet rot, is the rotting of unseasoued
timber, by what we may call the fermen-
tation and subsequent putrefaction of its
own sap.


Dry rot is similar result produced
by causes external to the timber itself, q
humid atmosphere aud want of ventila-
tion,-being however almost always, if
not Invariably, attendant causes. From
Noah, down to the present time, the pre-
servation of wood has been a constantly
agitated question. There are some plans
| for this purpose that are too costly for
practice on a small scale. For instance,
the process of Kyanizing, performed by
soaking timber in a solution of chloride
of mercury. This is dangerous poison,
and the men employed in the work be-
come subject to salvation, and thus q
practical difficulty arose. Another OBJ
lection was its cost, it was too expensive
to be used efficiently at paying price
for the market.


Another meth ID was soaking in a So
luton of sulphate of copper, the blue
vitrol of commerce. This is too costly
for small parcels. Burnetizing, another
plan is solution of chloride of zinc.
This hardens the wood, but does not
protect it from the effects of the atmos-
phere.


Yet, still another process is carried on
by using two solutions in succession, sui
phate of iron and carbonate of soda,
which will form oxide of iron in the
pores of the wood.


There is a difference in timber in re
gard to its durability. The piles of old
London bridge, were of elm, and after
being driven into the ground under water
for 500 years, those that were removed
in the course of erection of the new
bridge were as sound as when they were
first driven.


Here is another process which has OBJ.
tanned over all others, and has been used
In Europe with great success for over
twenty years, the cause of decay in wood
| is simply found in the different substances
of which the wood is composed, its al
bumen parts act as yeast to all the others
and excite fermentation, which finally
ends in the destruction of the entire wood.
| The great cost and consequent neglect of
ated by DR.. Karmrodt, for by it the tim
Der can be prepared in the woods. and no
machinery is necessary.


Muriate of barytes when applied to
the end of log of wood, will quickly
force itself through all the pores, with
out any artificial pressure, driving the
sap out at the other end; then if so
luton of sulphate of copper is applied,
the following chemical process takes
place: By the action of the muriate of
| barytes, the sulphuric- acid combinations
of the wood becomes fixed, the more
easily soluble elements disappearing, and
results in the formation of the more diff
fcult soluble salts of baruim 1t SO
luton of sulphate of copper (blue vitrol)
is then applied. considerable number
of combinations is formed, especially
sulphate of barytes insoluble in water
and which cannot be soashed ascay. while
the oxide of copper formerly contained
in the sulphate of copper enters into
chemical combination with the other or
ganic substances, gray colored spots con
tanning chloride of copper, finally ap.
pear in the wood, proving the successful
termination of the operation. This can be
done at any season of the year when
frost win not affect the free running OF
the sap. The months between April
and October being best for the purpose.
HICKMAN, April 1870. q. Il.
|