May 12, 1916.

THE COLLIERY GUARDIAN.

897

The Chairman asked how, in the event of one of these
large trams getting off the road, they would get it back
again.

Mr. Strachan had seen one man, fitted with a back
leather, lift a tram back on the road by himself. The
trams were 6 ft. long, and held from 30 cwt. to two
tons.

The Chairman thought that the trams were a more
perfect piece of machinery than those in this country,
to which Mr. Hepplewhite added that the trams ran
on springs, and had ball bearings, so that they were
actually better than railway wagons; but they must
have very nice floors to run on. He was also struck by
the coal-cutting machines and the overhead trolleys,
though of the opinion that conditions in this country
were too unfavourable for the use of such machines.

The Chairman said that we in England ought to
bestow more care on our tubs.

Fuel Economy.

Mr. Bramall, in opening the discussion, said that at
all the collieries where there was a good deal of water,
the amount to be pumped was about the same. Pump-
ing took nearly as much fuel as the coal, and he thought
they would have to look forward to an increase.

The Chairman suggested it would be better to cen-
tralise the power; but Mr. Bramall said this could not
be done, and remarked that the only way to reduce
consumption was to utilise the exhaust steam from the
winding engines by turning it into electricity, which
could only be done by those who were already pre-
pared, machinery being now unobtainable. Patent
furnaces had not been a success with him.

The Chairman said that for automatic furnaces the
fuel had to be broken up to a uniform size.

Mr. Hewitt confirmed a remark that the use of
washed nuts caused a very great improvement in the
fire and the steam, while the ash was very small indeed.

This concluded the meeting.

GOAL PRODUCTION CONFERENCE.

At the request of the Government, the executive of
the Mining Association of Great Britain and the
executive of the Miners’ Federation of Great Britain
(as intimated in our columns last week) will meet in
joint conference in London next Tuesday to consider the
question of a greater production of coal.

COAL WASHING PLANT AT MANOR-
P0W1S COLLIERY, STIRLING.

At the new colliery at Manor-Powis, not far from
Stirling, owned by the Manor-Powis Coal Company
Limited, all the plant is of the latest type, and planned
for a large output; but special mention may be made
of the installation of coal washing plant (fig. 1), designed
and fitted up by the Simon-Carves Company,
Manchester.

The fine coal from the screens is brought to the
washery either by the scraper conveyor and delivered
into the feed hopper, or delivered directly by
a shoot into the feed hopper. From the hoppers the
coal is elevated by the feed elevators into their respective
washing boxes, and from these it is swilled along a shoot
on to the jigging classifying screens (fig. 2), where it is

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Fig. 1.—Washery with

Elevated Settling Tank.

classified, in one case into trebles, doubles, singles,
pearls, and duff; and in the other case into doubles,
singles, pearls, and duff. The sizes from pearls upwards
are delivered directly into the storage bunkers under-
neath the screens, while the duff is swilled along a shoot
to the draining sieves underneath the settling tank.
The slurry and water pass through these sieves, and :nto
the pump sump, while the duff passes over the sieves
into the small draining conveyor, delivering at the top
end into a shoot arranged to load into wagons on the
spare road. Alternatively this duff from the draining

NOTES ON MARITIME COALING
STATIONS.

By F. J. Warden-Stevens, M.I.M.E., A.M.I.E.E.

To realise the importance of coal in connection with
British shipping, consideration must be given to the
extent of coal cargo shipments in comparison with total
exports, and account must be taken of return cargoes
by reference to imports; then the dependence on coal
shipments for tonnage, and the effect on freights and
oversea commerce will be appreciated.

Further, coal being a necessity for a steamship service,
and forming the largest item of cost, the economical
working of that service is dominated by the commercial
value of coal for its specific use, this value being based
on cost per mile per ton propelled, and cost for bunker
space occupied. The best financial results of a steam-

ship service are, of course, obtainable by maximum earn-
ing power with minimum working costs. Now, earning
power, it will be understood, is increased on long
voyages, when freights rule high, by facilities to coal
en route, thus allowing greater cargo capacity, and, in
the case of “tramps,” provides for longer voyages and
deviation from routes for return cargoes; thus we arrive
at the importance of ocean coaling stations.

As regards working costs of a steamship service, as
coal forms the largest item, it should receive the greatest
consideration, and from several points of view. The cost

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Fig. 2.—Classifying Screens.













Fig. 3.—Washer Box Floor with Dirt Elevators.

The position in which the nation stands with regard to
its coal supply will be best appreciated by a comparison
of the number of men employed in and about the mines,
and the aggregate quantity of coal produced in the years
1914 and 1915. The production for the years named
was :—

1915 .............. 264,497,263	tons.

1914 .............. 279,085,473	tons.

This shows a diminution in output in 1915, as com-
pared with the previous year, of 14,588,210 tons. But
it has to be borne in mind that in 1914 the country was
at war for five months, and in that period there was a
falling off in production as compared with 1913 of
14,824,702 tons. Thus the diminution in production
with which the country is really confronted amounts to
29,412,912 tons.

The reduction in output is entirely attributable to the
patriotic response made by miners to the nation’s call for
men. The number of enlistments in the first 13 months
of the war was 250,750, and of these 56,850 enlisted
between March and August 1915. It is probable that
the number of men enlisted has now increased to
300,000, as skilled miners have been required for
tunnelling and other similar work.

It is estimated that 60,000 are in the pits to escape
military service. This circumstance may be discussed
in connection with the proposed suspension of the eight
hours rule and the question of absenteeism.

conveyor can be delivered into the worm conveyor to
be carried across to the boilers. The slurry and water
collecting in the pump sump is elevated by a centrifugal
pump into the settling tank (fig. 1), where it is clarified.
The clear water from the top of the tank flows by gravity
to the washer boxes in the washery; and the slurry col-
lecting at the bottom of the bank is let out and regulated
by means of a tap on to the slurry refining plant,, where,
after treatment, it is delivered in a fairly dry condition
into the draining band along with the duff.

The dirt from the washer boxes is elevated by the
dirt elevators (fig. 3), and delivered into the dirt
bunkers, these bunkers being arranged to deliver on to a
shoot underneath for loading into tubs on a gantry
running alongside the screens. The trebles, doubles,
singles and pearls bunkers are arranged with outlets
and slides to deliver into wagons on sidings running
underneath the washery. The compressed air required
for pulsating the water in the washer boxes is provided
by the air compressor.

All the apparatus in the washery can be driven by
one motor of 75 horse-power; and a 75 horse-power
motor is also required for driving the pump and slurry
refining apparatus underneath the settling tank. The
screen over the anthracite picking belts is arranged with
a three-way shoot to deliver, if necessary, into a breaker
in place of on to the picking belts. An elevator is also
provided to lift coal after passing from the breaker
back on to the anthracite cobbles belt.

of coal at the coaling stations depends not only on its
quality and cost at the pit’s mouth, but the facilities for
delivery, and distance from the colliery. The question
of quality of coal doubtless requires greater attention
than it sometimes receives, having in mind suitability
for the particular vessel and voyage, and with the object
of reduced cost per mile ton. Not only at terminal or
coal ports should suitable supplies be obtainable, but at
coaling stations. Also, increasing competition, labour
unrest, and varying freights, as well as more exacting
demands for quality, quicker despatch, and reduced
breakage, necessitate changes in arrangements for sup-
plies in order to meet the times. The facilities for
delivery and distance from the collieries have doubtless
the greatest effect on the ultimate cost of coal for steam-
ship supplies at coaling stations, and we may now
proceed to note briefly the conditions and requirements.

(1)	Conveyance from the Colliery to the Port of
Shipment.—If by rail, the class of wagon is of some
importance, but is dependent on the method of ship-
ment available—a self-discharging and large capacity
wagon is advantageous; if by canal, large .open type
barges, as adopted on the Rhine, or special tank barges
as discharged at Goole, provide ease of transhipment,
conditions permitting. Further, shipment from private
wharves offer other opportunities—special trucks, aerial
ropeways (for long distance conveyance), etc.

(2)	Storage before Shipment. — In this connection
there is the question of storage at the colliery, or near