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The Wisconsin Lumberman.
taking fire by means of sparks from
the engine, is greatly lessened. This
last property entitles the process to
a careful consideration of its utility
in ships and steamboats, where por-
tions of the timbers are extremely
liable to take fire by the continued
action of an elevated temperature
from the heated machinery, boilers,
and from other causes. The trifling
expense of preparing the timber is
of little account, when the question
is one of even partially diminishing
the liability to the terrible conse-
quences incident to the burning of a
ship at sea.
Burnettizing also protects wood
from the attacks of insets, which, in
certain localities, are as destructive
of the strength and durability of
timber as the most rapid process of
decay.
The object of this and other pro-
cesses is the preservation of wood,
cordage, canvas, etc., etc., from wet
and dry rot and mildew. The im-
portance attached to this, and the
extent to which investigation and ex-
periment have been carried, is shown
by the fact that no less than forty-
seven patents have been secured for
processes to secure this result, most
of them within the past century. 01
these, besides Burnett's, the mosi
generally known and used, are prob.
ably Kyanizing, and the creosote oi
coal-tar process.
Kyan's process, patented in 1832
though attended with good results
is open to serious objections. Cor
rosive sublimate, or bichloride o
mercury, the substance employed ii
very expensive, which is a sufficien
objection to its general use. It is
moreover, a virulent poison, and the
process requires several weeks for its
completion. From the corrosive
action of this substance upon most
metals, it cannot be used in close
iron vessels, the advantages of ex-
haustion and pressure are thus lost,
by which alone can timber be
thoroughly impregnated and the
process finished in a few hours.
In 1838, a patent was granted in
England to Sir Wim. Burnett, for the
use of chloride of zinc in the preser-
vation of certain animal and vegeta-
ble substances from decay. This
process has been extensively used in
England, and more extensively in
this country than any other. The
chloride of zinc has proved to be
effectual, and has the advantage of
being safe, cleanly, and economical,
while at the same time it acts as a
purifier.
Burnettizing was introduced in
this country by James B. Francis,
Esq., agent of the proprietors of the
locks and canals on Merrimac river,
at Lowell, Massachusetts. This com-
pany, the original proprietors of all
the water power used by the exten-
sive manufacturing companies of that
icity, have many uses for lumber
in exposed situation. s, as in bridges,
locks,dams, sluices, etc. Mr. Francis,
their agent, a distinguished civil en-
gineerthoroughly examined the vari-
ous processes for preserving timber,
aud in the course of his investigations
visited some of the largest estabish-
- ments abroad.    Satisfied of the
f utility of the Burnett process, at his
3 suggestion, and under his direction,
t the works at Lowell were erected.
i. These works were put up solely for
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