The Black Hills union and western stock review. [volume] (Rapid City, S.D.) 1904-19??, 1909-01-22
THE TIMBER
and MINING
ARE VERY CLOSELY RELATED
ACCORDING TO GOVERN
NlENT ENPERT.
DETAILED STATEMENT OF PART
TIMBER HAS IN PRODUC-
TION OF WEALTH.

| Washington, Jan. 19.-"Few per-
sons not directly interested in min
| ing realize the extent to which tim
Der is used in this very important
industry said a government expert
representation of mine timber, who
has just returned to Washington
from the west. The average man
| has only vague understanding of
the Importance Of the part that tim
Der plays in the mining industry,
and seldom thinks of the enormous
quantities required each year to pre-
vent the caving of the over-hanging
ground and to keep clear the main
working passages of mines.
There are two general classes of
such timbers," he continued, "the
first is used in bracing the Slopes
as they are called, where the ore is
being taken out. AS the ore is
mined, the surrounding rock is held
in place by bracing it with heavy
timbers, framed into rectangular
sets When ore directly above the
first set is removed, second set is
built in on top, and so on. The SER
vice of these timbers ends when the
ore is exhausted and the active min
ing transferred to another vein or
ore-body.
after a time these timbers de-
cay, to a point where the pressure
of the rock walls brushes them, and
a 'cave-in' occurs. This causes no
damage if, as l have said, the min
ing work has been finished; but it
sometimes happens that decay has
weakened the timbers to such an ex-
tent that the cave-in occurs prema-
turely, and then lives are sacrificed.
In such cases the remaining ore is
also 81 loss, for when the ground has
once commenced to move or work,
as the miners call it, it is almost i'm
possible to clean it out and hold
back the rock so that the remaining
ore may be obtained.
but of still greater Importance
is the second class of timhers used
in the main working openings, tun-
nels, shafts, etc, which are to be
maintained for as long time as
possible. Timbers for this service
are chosen not only for their
strength and firmness, but also for
their ability to resist decay.
'In nine cases out of ten, when
timbers are crushed, the indirect
cause is decay, produced by low
forms of plant life. The dwindling
Of our timber supply has driven con-
sumers of wood all over the country
to study decay and its prevention,
and it is safe to say that in the very
near future we shall see many more
mines putting in small plants for the
treatment of their timbers, after the
pattern of the plants that have been
designed and installed for this pur-
pose by the United States forest ser
vice. BY treating the permanent
| timbers with some one of the various
preservatives, they may be made to
resist decay almost indefinitely. The
additional cost is slight.
| "Not only this, but since timber
when it is once treated retains Its
original strength, many of the So
called inferior timbers' which have
|
valueless because they decay rapidly,
will find wide use in many localities.
Such species are loblolly pine and,
to certain extent, shortleaf pine,
imgelmann spruce, fire-killed lodge
pole pine, white fir, and many other
more local timbers.
"The first of the treating plants
| NJ hv n
eastern coal company, after extern
sive experiments in cooperation
with the forest service which dem
onstrated the practical value of the
treatments. Since then, other
plants have been installed in differ
ent parts of the country, two of the
latest being in the Occur d'Alene
lead district of northern Idaho,
where, while there is an ample tim
Der supply for some time to come,
the treatment is warranted by the
high labor cost of replacing timber
sets. The added cost Of treating
tjmbers is from 10 to 25 per cent OF
the original cost.
Gan interesting point in the prob
lem of wood preservation is the
spread of decay in old workings,
caused by infection from nearby
timbers. A fresh green post, placed
between two sticks that are already
sick, will become infected and de-
cay much more rapidly than II II
we're isolated. The contagion Is
similar to that of the Hills that man
is heir to, although it usually works
more slowly. In one large mine
two mile tunnel was completed eigh
years ago and during the first foul
years the timber stood up in finS
shape. Then signs of decay bega1
to creep in here and there, and since
then the disease has extended
throughout the entire length of thu
| tunnel, necessitating an annual ex
7 penditure of between four and fiv'
: thousand dollars for replacing tim
i bers rendered useless through de
: cay. Less than one-fourth of thi
Y sum goes for timber, the remainde
g representing the cost Of framing an
t installing. Internationally many o
a the cave-ins which crush the tim
: bers and block the mine tunnels
often causing many deaths. are du