692

THE COLLIERY GUARDIAN.

I

April 14, 1916.

SURVEYING INSTRUMENTS

WALKER BROS. (Wigan)
LIMITED.

Codes: ABC 4th & 5th, Lieber’s, Western Union, Moreing & Neal, Mining.

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AIR COMPRESSORS
with light Disc Valves to recent
Patents now at work (or on order)
indicating over

135,000 raising total output to 500,000 H.P.

PATENT UNLOADING DEVICE AND OUTPU1
REGULATOR, FOR POWER DRIVEN PLANTS.



Davis’s

Cranked

Dial.

Theodolites,
Levels,
Barometers,
etc.

DAVIS’S IMPROVED HEDLEY DIAL WITH CRANKED LIMB,
ENABLING SIGHTS TO BE TAKEN TO ANY DEGREE FROM
LEVEL TO 90 DEGS. UP OR DOWN.

Davis’s Surveying Instruments
are used in the majority of Mines in the
United Kingdom, the Colonies, and other
parts of the World.

PLOTTING INSTRUMENTS

for Railways, Mining Engineering, and Field work.

Ventilating1, Winding and
General Mining Machinery.

SEND FOR LIST Ro. 411 A.

JOHN DAVIS & SON

Pagefleld Ironworks, WIGAN.

Telegraphic Address : “ Pagefleld, Wigan.”	Telephone : No. 14 Wigan (2 lines).

(Derby) LTD.,

- ALL SAINTS WORKS, DERBY;

& 17, Victoria St., Westminster, London, S.W.

Telegrams—** Davis, Derby.” Telephone—240 Derby

JOHN WOOD & SONS, LT"

Engineers, BARLEY BROOK FOUNDRY, WIGAN.

Fitted with

AUTOMATIC BRAKE

FRICTION
CLUTCH.

and Improved

“ OUTSIDE-

BAND”

1OO-H.P. “ENDLESS”

Telephone—No. “ 55 ” Wigan.

Telegrams—“ Haulage, Wigan.”

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Haulage Gears of every type.

WINDING, PUMPING & AIR COMPRESSING ENGINES.