January 23, 1914.

THE COLLIERY GUARDIAN.

223

FOUNDED 1895.

THE
QUARRY,
The Organ of the

Stone, Marble, Slate,
Lime, Clay and
Cement Trades,

Circulating amongst

QUARRY OWNERS and
MANAGERS,
ARCHITECTS,
ENGINEERS,
SURVEYORS,
STONE MERCHANTS, &o.



2 MOST IMPORTANT POINTS

to have in mind when purchasing Machine-cut Gearing.

THE

GENUINE

Price—

6d. monthly.

Annual Subscription,
7s. 6d. post free
(payable in advance).

Offices—

30 & 31, Furnival Street,
Holborn, London, E.C.

DOUBLE HELICAL GEARS

Offer all this and more. Made from specially selected
material, with teeth accurately cut in one continuous
piece direct from the solid —they are an ideal drive
for heavy power transmission.

SILENT RUNNING.

David Brown & Sons <hfd> Ltd., Huddersfield.



M. COULSON & CO. LTD.,
SPENNYMOOR,
Makers of

Coal Washers, Screening Plant, . .

Conveying, Elevating, and Crushing
Machinery, Tipplers, Tub Controllers,
. . Storage and Drainage Bunkers. . .

Replace parts and Repairs given Special Attention.	Estimates and Full Particulars on Application.

4i

IB*



208 pages f’cap folio. Over a hundred illustrations and 60 plates (coloured).

PRICE 10s, (10s. 7d, post free).

RECORD OF

Established 1800.	—	Telephone No. 577*

BRASS TIME CHECKS

JOHN LAWSON & SONS,

Manufacturers of every kind of

STEEL STAMPS, LETTERS,
FIGURES, BRANDS, STENCIL

PLATES, &c.

Roebuck Letter Works, 26, Carver Lane, SHEFFIELD.

FIRST SERIES OF THE

BRITISH COAL DUST
EXPERIMENTS

CONDUCTED BY THE

COMMITTEE APPOINTED BY THE MINING ASSOCIATION OF
GREAT BRITAIN.

A Record of the Experiments carried out during 1908 and
1909 at the Altofts Experiments Station.

Published by—

THE COLLIERY GUARDIAN COMPANY LTD.,

30 & 31, Furnival Street, Holborn, London, E.C.

SUMSTED & CHANDLER Ltd.,

Engineers,

HEDNESFORD, STAFFS.

Telegrams—“Bags, Hednesford.’’	Telephone—48 Cannock.

FANS

for

MINE

Ventila=
tion.

F

High
Speed
Engines.

Centri=
in gal
Pumps.

Haulage
Gears,
&c.



Rever=
sible.

Above illustration shows our fan, steel cased, which does a higher duty In volume
of air passed than the larger brick-cased fan alongside.