coal trade bulletin - Clpdigital.org

educed individual efficiency may be more than
compensated by the increased aggregate output
produced without increased capital; but where
such shifting is adopted as a temporary measure,
there is, besides other reasons, a danger of overworking
the managing staff.
The cost of hand drawing, which the writer
terms the uneconomic gap, represents the most
expensive item on the costs sheet. A very common
practice in Scotland is to pay the miner a
hewing rate which includes drawing to a lye perhaps
500 yards outbye. It will usually be found
that two men are engaged in each place, one of
whom hews the coal, throws it to the roadhead,
stows the debris, and sets the timber. The other
man fills the coal and draws it to the lye. Then
if the tonnage rate is 3s., and 5 tons are produced
daily, the wage rate is 7s. 6d. If Is. per ton be
taken as fair remuneration for the actual filling
of the coal into the tubs, then the 3s. per ton
is apportioned as under: Hewing, etc., Is. 6d.;
filling, Is.; drawing, lid.; total, 3s. If the road
is 220 yards long, the rate per ton-mile is equal
to 4s. This is very high compared with endless
rope haulage at 3d. or 4d. and horse haulage at
Od. per ton-mile. Hand drawing is the most expensive
service rendered to the colliery.
In the case of a coal-cutter, the manager who
installs one in a section where tne draw is over
100 yards long is courting disaster, because the
cost of drawing more than swallows the prospective
economy; rapid clearing of the faces cannot
be done; and he has to commence w r ith a
high rate which he may find difficulty in breaking
when the length of draw is lessened. As a
matter of fact, tne question seldom arises, as
the air-pipes or electric cables are at hand, a
large output from a comparative short face is
ready, and mechanical haulage
IS EASILY ADOPTED:
hence hand drawing is practically eliminated. The
writer would venture to say that the advantages
and economies of mechanical coal-cutting do, in
very many cases, depend entirely on the large
output per face and the short draw. The machine
is, in fact, the occasion, not the cause, of
the economies.
In passing, the writer would express this opinion—that
unless in very hard or thin coal, or
other exceptional circumstances, if the face is
so short that a minimum of 60 tons per shift
cannot be got by a machine cutting to an ordinary
depth, cheaper coal can be got by hand, the
same drawing facilities being given in each case.
The conveyor face is another instance. A close
examination will show that the conveyor, where
successful, is so simply because it puts all the
coal from a given face at one point, from which
point efficient haulage can be applied, thus dis­
THE COAL TRADE BULLETIN. 37
pensing with hand drawing. Again, if inefficient
haulage is used in conjunction with the conveyor,
fewer men can be employed at the face,
a lower rate of advance is got, more debris is
required to maintain the face, and all the economies
disappear.
But as coal-cutters and conveyors cannot be
universally applied, hand cutting of coal must
continue, and mechanical haulage being out of
the question from a hand-worked face, the drawer
must be employed still. The question of the size
of the tub has already been touched on as one
of great importance, the objects being to employ
as cheap labor as possible, and to see that a
minimum of the drawer's time is spent actually
away from the face. The conditions, such as dip
of the seams, nature of the roof, extent of the
sections, and presence of faults, vary so much
in different collieries that no particular method
of economy could be universally applied. However,
it may be laid down that the drawing-roads
should be kept as short as possible, and in the
highest state of efficiency.
In order to make the roads efficient, the writer
suggests that the contour of every road in the
pit over which 20 tons or more per shift is drawn,
and on every road which costs extra money for
drawing, should be known. By
CONTOUR IS MEANT,
not the fixing of spot-levels on the plan, but a
regular systematic detailed contour of each road.
That is the first requirement necessary, in order
to minimize the use of mere physical or mechanical
force in transit. The roadsman has hitherto
ruled supreme by rule cf thumb on the drawingroad,
the cuddie-road,t the cousie § and the horseroad.
Let a very little modicum ot intelligence
be introduced.
The writer has used such a system for several
years, with very good results. The information
cannot always be made use of for economy, and
where "creep" is taking place difficulties intervene.
But, if the horizontal plan is practically
and legally necessary, why should not the vertical
plan (the contour) be determined and known?
The system practiced is as follows: A straightedge
10 feet long is used, and leveling is started
from the outbye end at a bench mark, or point,
the height of which with reference to the datum
line is known. At every third length leveled, a
mark is chalked on the side of the road thus—
3, 6, 9, etc. The leveling is never plotted, the
improvements to be wrought on the road being
determined entirely by arithmetic. In a table
used the total column shows at each point the
total height above the starting point. Column A
shows the height above the starting point at each
point on a mean gradient. In column B is shown
tCuddie-road = jig-brow, SCousie = a self-acting incline.