Nashville daily patriot. [volume] (Nashville, Tenn.) 1855-1857, 1857-01-14
Preserving--Burnetising Timber.

The preserving of timber with a solution of
the chloride of zinc-Sir William Burnet's
process-is now carried on at Lowell, Massa-
chusetts, and pamphlet recently published on
the subject by J. B. Francis, Esq, gives some
very useful information, which viii be of inter
est to-many of our readers.
Sir William Burnett secured patent for his
invention in England in 1888, but no Ameri-
can patent was ever taken out for it. 1t con-
sists, as stated in the patent, sin destroying
the tendency of certain vegetable and animal
substances to decay, by submitting them to the
action of a solution Of chloride Of zinc. In
preparing wood by this process, a suitable tank
is provided and filed about two-thirds full
with The solution, composed Of one pound Of
the chloride Of zinc 10 every five gallons Of
cold water" The timber, (by the plan first
proposed by the inventor was stepped in this
for about twenty days, when it was taken out
and dried under sheds. This process was first
introduced into Lowell in 1850, by the proprie-
tors of the locks and canals on the Merrimac
river at the joint expense Of the manuiactur-
ing companies. The original intention simply
was, to prepare timber for their own purposes,
but the apparatus erected was found to be ca
pable of preparing more than they required
and accordingly they have also prepared con-
siderable quantities of lumber for other parties.
The price charged is, for spruce lumber, 50
per 1000 feet, board measure for all other
kinds of lumber So; shingles, 20 cents per
1000. Spruce, it seems, does not take up so
much of the solution as other kinds Of timber,
and this is the reason why it is cheaper. About
one million feet, board measure, have been Bur-
netised annually since the apparatus was erect
ed. This apparatus consists Of cast-irOn
cylinder an inch thick, in which the timber to
be prepared is placed it is 60 feet long, feet
diameter inside, with one head movable.
pair of rails of about two feet gauge are laid
on its bottom, a heavy truck is loaded with
timber, which is chained down to prevent it
floating, and it is then run upon a railroad into
the cylinder, and its movable head put on per-
fectly tight. A wooden cistern containing the
chloride solution lies below the iron cylinder
An air pump, of twelve inches diameter and
three feet stroke, and force pump, four inches
diameter and two feet stroke, are employed,
and worked by small steam engine, which
also warps the timber in and out of the cSlin-
der The air pump exhausts the air from the
cylinder and timber, when the solution flows in
by atmospheric pressure from the cistern. The
air pump then gives place to the action Of the
force pump which forces in the solution until
it attains to a pressure of $50 pounds on the
square inch, at which point it is maintained for
two hours, when the process is completed
| The surplus Of the solution not taken up by
the timber, is then run off, and the prepared
timber run out, to make room for another
batch.
The time required in performing all the ope-
rations and operating on 1000 feet-board mea-
sure-Of timber, is seven hours; but two
| patches can be prepared every day, by allowing
one batch to drain off during night. The
strength of the solution employed at Lowell is
one and a half measures of the dry chloride of
zinc to a hundred measures GALLONS it may be)
of water; the chloride used is obtained from
manufacturers in the condition of a cOncen-
trated solution containing 10 per cent. of water.
The apparatus described is the same as that
employed in Gloucester, England, under Bru-
mel, for preparing railroad timber, which estab-
lishment was visited by Mr.. Francis in 1851.
A thousand feet Of timber-board measure
if it is dry will take up nearly forty gallons Of
the solution; wet timber takes up less.
Since the time this company commenced to
preserve wood in this manner sufficient time
is scarcely elapsed to test the timber, treated
fairly. The timber on the Charles River Bridge,
over an arm of the sea near Boston, was 50 pre-
pared in 1850, but it has now decayed to a
considerable extent. 1t was young pine, Sc
cond growth, and contained great quantity of
sap On the other hand, the timber prepared
for the Lowell Bleach Works has been perfectly
successful f. P. Appleton, Esq, the agent
of the Works, in a letter to Mr.. Francis, states
that plank road of Burnetised timber, 200
feet long, was laid down in 1850, and alongside
of it, portion of the same lot of timber, not
so treated, was also laid down. The latter is
now wholly decayed, while the prepared tim
Der is as sound as the day on which it was OBJ
tanned. The ground walks around the Works,
laid with spruce plank unprepared, did not
last over two years, but Burnetised spruce,
used for the same purpose, has stood six years.
and is still sound. The shingles, clapboards
and other timber used in these Works, have all
been Burnetised, and the advantages have been
very great Samuel l.. Dana, chemist, at the
Merrimac Calico Print Works, also adds ia
vorabe testimony to the value of BurnetIsing
timber for some purposes.
As this process is common property, it APP
pears to us that it ought to claim the attention
of our railroad companies, for the preserving
of the timber which they require in such i'm
mense quantities. We believe that the New
| York Central, the New York & Erie, the Hi
nois Central, and other great railroads, would
each find it to their advantage to erect such an
apparatus as that described, and thus treat all
their sleepeTs, and other like timber. The
same process and apparatus will answer for a
different solution, such as the sulphate Of cop
per, which is employed by Dr. Boucherie for
railroad timber in France, and which has been
asserted to be superior TO the chloride of zinc.
At any rate, it cannot be doubted but that TIM
Der so prepared with either of these solutions,
will endure much longer exposed to the wea-
! Their than unprepared timber, and thus be the
means of saving large sums Of money annually.
Timber can be prepared for bridges, houses,
&c, without the use of the apparatus descrb-
| ed,) by simply immersing it in the solution in
tank for about twenty days. Owing to the
rapid consumption Of timber in our country
since railroads became so numerous, thus caus-
ing great rise in its price, it will be short
! sightedness, we think, on the part Of those
companies who expend so much for it every
year, to neglect this subject much longer.
MARRIED,