December 22, 1916.

THE COLLIERY GUARDIAN.

1211

	
•	• • trade • •  •	• • M A R K ■ •  Steam Heater Units  for  FACTORY HEATING.  Advantages of the Unit System :  Absence of air ducts, which obstruct the light, and in some cases would interfere with the overhead gear in a shop.  Sirocco Heater Units only require steam and drain connections and cables to the Electric Propeller. The :	Units occupy very little floor space. The temperature can  be regulated at each Unit, consequently no steam is wasted by overheating some portion of a building in the effort of maintaining a desirable temperature in some other portion. The warm air is delivered near the floor level where it is most needed. Extensions to the Unit System are easily carried out, and it will be found invaluable for supplementing existing and insufficient Heating Plants. The Units can be readily removed and installed in a new position when necessary.  Send for Folder No. 3074C.  DAVIDSON & Co. Ltd. I  SIROCCO  Engineering Works,  BELFAST  s’ ..	
	
G% TO 3% SAVING IN FUEL, OR 1 2^ TO "’5% MORE STEAM  i  J4	X.	. ■	-  Ty  I ERFEctx  CIRCzULLA.POR. 39, Victoria Street, London, S. W.	
ANNALS OF COALMINING & THE COAL TRADE  By Post, 25s. 9d.	BY ROBERT L. CALLOWAY.	Price 25s. net.  The Colliery Guardian Co. Ltd.. 30 & 31, Furnival Street, Holborn, London, E.C.	
	
CEMENTATION and CHEMI CAL TREATMENT	
YEARS of STU RY T0 colliery proprietors.  ■	Shafts sunk, tunnels driven, and  aBlU SX/ka SZhnBELlwOSL	other mining constructions carried  10 MF*	out ’n	anc* very wet ground  HAVE BoOUbH 1	by the best method. Success guar-  anteed.  IWY SYsTERfl OF	18 shafts completed in England,  E NT A T 1 AIU	and 7 in progre,s-  G IW E 1	8 Sull	Ferro-Concrete Lining a speciality.  "S"O DCOE'K’tf^TlOE^	Feeders of water in shafts or levels  1	r~tnrE.U 1 lUSl.	effectually treated.	

PLOWRIGHT BROS. LTD.,

Brampton Iron Works, Chesterfield.

Speciality—

COAL SCREENING. CONVEYING

i 1 r

Uli

■' *

-^1

■ > -

L Ml

■

L - S

■;.. ••> £

SECTION OF SCREENING PLANT AT BENTLEY COLLIERY, DONCASTER.



CONSIDERABLY OVER.

109 PLANTS

NOW AT WORK IN
GREAT BRITAIN
AND THE COLONIES.

Estimates and Designs on application.

Agent for South Wales: A. LEIGHTON STEVENS, 15, Fields Road, Newport, Mon.

PK IN

21 r i r~~r i i f i r 11 i

K__JL it Jl J(H Jgugaa

PATENT

SHELTERED SEAT TRYCOCK

For ------------------

GAUGES.

. 668 5.

SPECIFY FIG. 6 68 5
Sent on Approval.

■ij

ADVANTAGES

NO ASBESTOS PACKING
TROUBLES.

No plugs to work loose
and leave the packing faces,
causing cutting and leakage.

No circular action to cause
grooving.

Easy method of operating,
as there is no packing fric-
tion to overcome.

Is not affected by expan-
sion.

Large outlet for discharge
of sediment, &c.

Self Cleansing.

Main valve opened and
closed at atmospheric pres-
sure. which overcomes the
cutting action of the steam
and water at the point of
opening and closing.

VALVE AND SEAT OF

HOPKINSON’S “PLATNAM”

METAL.,
which does not cut and score
like gunmetal & other alloys.

Upwards of Jons of Standard Steel Castings kept in stock,
lie can give immediate delivery of iron and steel valves.

Illustrated Catalogue Post Free on Application.

J. HOPKINSON & C° LD Huddersfield.

Makers of Patent Safety Boiler Mountings and Valves

For High Pressure Superheated Steam, High-class Exhaust and Water Sluice

Valves for Condensing Plants, &c., Automatic Exhaust Valves, Reducing

Valves, Steam Traps, &c.. &c.

Depots and Showrooms—London, Glasgow, Edinburgh, Cardiff,
Oldham, Blackpool, Paris & Petrograd.

No. 374.