The Mining Magazine, Vol. 75, No. 3

i he ivlímng Magazine

V O L T lX X V .

3. LONDON, SEPTEMBER, 1946.

THE ENGLISH ELECTRIC COMPANY LIMITED

London Office: QUEEN’S HOUSE, KINGSWAY, LONDON, W.C.2

INDUSTRIAL MOTOR WORKS - - - BRADFORD

‘ENGLISH ELECTRIC’

FLAMEPROOF MOTORS

VVr/'te ^{fo r}

descriptive lite r a t u r e

£"Z- - THE MINING MAGAZINE

One of a number of Heavy Duty Sledgers being manufactured by Fraser and Chalmers.

F. and C. Heavy Duty Sledgers are designed to crush run-of-mine ore, capacities 200/800 tons per hour. These are massive machines—equipped with automatic lubrication and water cooled bearings—

specially designed to meet the demand for large outputs required by mines and quarries.

FRASER & CHALMERS ENGINEERING WORKS

EFtlTH, K ENT. lom dok o ffic e ; magnet house, kikcsway

3—1 3

C P S ®

M A K E S T H E G R A D E

E V E R Y INCH

A SC R EEN

P EG SO N -TELSM ITH

G r a d i n g for g re a te r

uniform ity and profit

The alloy steel shaft of the vibrator unit of the Pegson-Telsmith Heavy Duty Screen rotates in cylindrical self-aligned roller bearings mounted on the horizontal frame of the screen. The eccentric action of the vibrating unit produces a circular movement counter to the flow of the material—

a perfect grading action. The screen is supported In its compact, rigid frame by groups of adjustable springs at both ends. The reaction between the vibrating unit and the screen itself is perfectly

balanced so that the vibration of the screen is entirely confined to the screening deck. The Pegson-Telsmith Heavy Duty Screen was designed by engineers who built the machine to do a better and more uniform job of grading, at higher speed and lower cost. The result is a screen that makes profit for its users under most exacting conditions.

May we send you full details with convincing figures concerning the screen’s performance. Your letter will bring full, immediate reply.

PEGSON LTD .

Iddesleigh House, Caxton S tre e t, W e s tm in s te r, London, S . W . I

W o r k s : C o alville, Leicester. P h o n e: Abbey 2373.

4

THE MINING MAGAZINE

Woven Wire

in any Gauge or Mesh for all Screening and Grading

Operations

W rite for Catalogue M269

G .A .H A R V E Y & C o .( london )L td .

W O O L W IC H R O A D . LO N D O N . S . E . 7

6

THE MINING MAGAZINE

FLAMEPROOF

MOTORS

F L A M E P R O O F M O T O R S U P T O 1,000 H.P.

/Squlrrel-cage from } H.PA V. Slip-ring from 5 H.P. )

and

A N E X T E N S IV E R A N G E O F F L A M E P R O O F C O N T R O L G E A R

For use in collieries, oil refineries, paint and varnish works, spray booths, and any situation w here inflammable

Totally-enclosed Fan-cooled Squirrel-cage Flameproof Motor

All-steel cyclindrical frame motors and gate-end control

1D ' F I I r

ground conveyor drives

etc

J

B T H

T H E B R I T I S H T H O M S O N - H O U S T O N C O M P A N Y L I M I T E D . R U G B Y , E N G L A N D

A U S T R A L IA . Sydney:

Australian General Electric Proprietary Ltd., G .P.O . Box 25 17.

Melbourne : Australian Gen­

eral Electric Proprietary Ltd., G .P .O . Box 538-F.

N E W Z E A L A N D . Welling­

ton : National Electrical &

Engineering Co., Ltd.. P.O . Box I055.

P rincipal O verseas R epresentatives for the B T H Com pany : IN D IA . Calcutta:

Associated Electrical Indus­

tries (India) L td., P .O . Box 271.Bombay : Associated Elec­

trical Industries (India) Ltd., P.O .B ox 484.

C H IN A . Shanghai : Inniss &

Riddle (China) Ltd., 43, Yuen Ming Yuen Road.

Hong Kong : Inniss & Riddle (China) Ltd., 1st Floor David House. 67-69, Des Voeux Road Central.

R H O D E S IA . Bulawayo:

Johnson & Fletcher Ltd.. P.O . Box 224.

S O U T H A F R IC A . Johannesburg : Wilson & H erd Ltd., P .O . Box 7733.

Capetown : Wilson & Herd, Engineering (Pty.), Ltd. P .O . Box 1459.

W E S T A F R IC A .

Sekondi, Gold Coast Colony ; T he W est African Electrical Co., P .O . Box ⁸.

K E N Y A . U G A N D A , T A N ­ G A N Y IK A .

N airobi: R. G. Vernon & Co., P.O . Box 124.

N airobi: British East Africa Corporation (1939) Ltd., P .O . Box 182.

Dar-es-Salaam : Lehmann s (Africa) Ltd. (for lamps only), P.O . Box 163.

an d others throughout the w orld.

CROSSLEY

SCAVENGE PUMP D IESEL ENGINE

EXHAUST ^p

o

E CHARGED

L o o p S c a v e n g e — 9 0 % E f f i c i e n c y

Incorporating Kadenacy proportions of Ports, Timings, etc.

CROSSLEY BROTHERS LTD. M A N C H EST ER , 11

8 C 2 6 8 A

THE MINING MAGAZINE

9

W I N D I N G

S lB r STATION

GOAL FACE

This Company, as special­

ists in Mining Electrical Engineering, manufacture W in d e r s , S w i t c h g e a r , Transformers, Generators, Motors and Control Gear designed to meet the many and varied applications above and below ground.

E L E C T R I C A L " --- ---C O .. L T D .

T R A F F O R D P A R K - M A N C H E S T E R 17.

* Forqe saves ⁸⁰⁰ tons of

coal a if ear; increases production

What is Thermal Linkage ? It is a proved, practical method of getting maximum work from total heat supplied. In brief, Thermal Linkage integrates your various heat-using processes and, as far as possible, operates them as a single co-ordinated heat-using unit. Instead of being independently supplied directly to separate consumption points and the surplus from each going to waste, heat is circulated and re-circulated (o extract from it the last ounce of work.

* C a p ita l o u tla y reco vere d in 13 m onths

T H E P R O B L E M : 14 x 1 0 cw t. steam hammers installed in two shops: 7 in constant use, demanding 5,000 lb. of steam per hour over a 58-hour week ; additional 3,000 lb. of steam an hour for space heating; 700 lb. per hour lost through leakage. Boiler needed 40 tons of washed trebles per week during winter. 2,000 lb.

of condensate pe’r hour ran to waste.

A C T I O N T A K E N i n c l u d e d d e t a i l improvements in boiler plant and steam trans­

mission. Steam pressure at hammers reduced from 100 to 80 p.s.i. and foot controlled cut-off valves installed. Feed pump exhaust taken through a coil in feed tank. Most of space heating load carried by exhaust steam without interfering with hammer operation. Surplus exhaust sent to hot well. Condensate return system installed. Only 5,300 lb. of steam required. Rough smalls substi­

tuted for washed trebles. 800 tons of coal p a.

saved. Production increased through not having to stop hammers owing to shortage of steam.

Capital outlay (£1,904) recovered in only 13 months.

FOR COMPLETE DESCRIPTION SEE “ FUEL EFFICIENCY NEWS,” SEPTEMBER, 1945

Consider this N O W

W hether or not you are reconstructing or reconverting your plant, consider this question now :— W hat economies can Therm al Linkage achieve in your plant?

FO R G E N E R A L IN F O R M A T IO N ,

see Fuel Efficiency Bulletin, No. 21.

FO R S P E C IF IC A D V IC E ,

contact the Regional Office o f the M inistry o f Fuel and Power.

B E F O R E

An example of what

THERMAL LINKAGE

can do *

THE MINING MAGAZINE

The 24-RB Electric Shovel shown here has a I yard dipper and is excavating and loading opencast coal.

For 70 years the leading name in

EXCAVATION

R U S T O N - B U C Y R U S L T D . , L I N C O L N

E x c a v a t o r S p e c i a l i s t s

11

3 a B o rtz Bits are Cost Reducers.

W h it e o r yellowish diamond crystals, to o small o r im perfect for gem use, are called bortz. In a medium sized bit th ere are approxim ately 300 crystals mechanically-set in an alloy metal m atrix.

Bo rtz is harder and sharper than carbon, w ith a cutting action requiring less pressure. Bo rtz bits have largely

displaced the old carbon bit for tw o prim e reasons :

(1) The initial cost is much less—

about 1 /50 that of a carbon bit.

(2) D rillin g costs are reduced, due to increased footage per bit and m ore rapid drilling progress. B o rtz bits cut faster and can be run at higher speeds.

Th e L O N G Y E A R Prospector

U se s B o r tz B its

H ere is a light, air-driven model for under­

ground use w ith a capacity of 300 ft. Mounted on a column o r mine bar, it is ideal for drilling in drifts, raises and in narrow mine openings.

An electric m otor drive is available if desired.

The screw feed drilling head has th ree sets of feed gears. B it rotating speeds up to 1,200 r.p.m.

are obtainable. C o re samples recovered are

|-in. in diam eter.

The Prospector is a practical, low-cost machine and w ith bortz bits you are assured of operating econom y. W r it e for particulars.

CANADIAN LONGYEAR, LIMITED, North Bay, Ontario, Canada

L O N D O N REPRESEN TA T IVE

A U S T IN H O Y A N D C O M P A N Y , L I M I T E D , 39, St. James Place, S.W . I O th e r representatives in O slo , N orw ay ; H elsin k i, Finland ; Johannesburg, S . A . ; Perth,

W estern A u s t ra lia ; W ellington, N ew Zealand.

12

THE MINING MAGAZINE

ANNUAL A D D IT IO N S FOR THE F L O T A T IO N I N D E X

T ech n ical lib ra rie s a n d mining schools, a s w e ll as a ll persons in te re ste d in flota tio n , a r e in vite d to use this C o up on . Flo tation inform atio n is a frie n d ly se rvic e o f G r e a t W e s te r n Division, The D o w Chem ­ ic a l C o m p a n y , p io n e e r p ro d u c e r o f X a n th a te s fo r m e ta llu rg ic a l use an d sole m an ufactu rer o f B e a r B ran d X an thates.

To maintain the most complete, authoritative guide to published material on the flotation process . . . obtain our sixteenth annual additions for your BEAR BRAND FLOTATION INDEX. M any of the listings and descrip­

tions of books and manuscripts in the 1946 compilation are of particular note. If you lack any or all previous index additions, request the missing years.

“ FLOTATION FUNDAM ENTALS” — a comprehensive vol­

ume covering the broad subject of flotation in plain language— is also yours on request without charge.

G R E A T W ESTER N D IV IS IO N » T H E D O W C H E M I C A L C O M P A N Y • S A N F R A N C IS C O , C A L IF O R N IA , U . S. A .

BEAR^BRAND

XAN TH ATES

13

i---1

G r e a t W e s t e r n Division, The D o w C h e m ic a l C o m p a n y I (D e p t. C ), 310 S a n so m e St., S a n Fran cisco 4 , C a lif. .

|~1 Y ou m a y send me (w ith o u t c h a r g e )... * cop ies o f the current ad d itio n s to b rin g m y B E A R | B R A N D Flo ta tio n In d e x up to d a t e .

□ Y ou m a y send me (w ith ou t c h a r g e )... j c op ie s ofthecom p/efe B E A R B R A N D Flo tation In d e x . |

□ Y o u m a y send me (w ith ou t c h a rg e ) a c o p y o f |

"F lo ta tio n Fu n d am en tals."

N a m e ________________________________________________________ I A d d ress_____________________________________________________ I Firm N a m e I __________________________________________ I

Position ' |

M I N I S T R Y OF N A T I O N A L I N S U R A N C E

Increases in National Health and Pensions Contributions

as from

In view of the substantially higher rates of Old Age Pensions which will in future be payable under the Contributory Pensions Scheme, the

rates of Pensions Contributions are being raised.

N E W R A TES

HEALTH A N D P EN SIO N S IN S U R A N C E C A RD S O F PER SO N S IN S U R A B L Y EM PLO YED MUST BE STA M PED A T TH E F O L L O W IN G W E E K L Y RATES O N A N D A FT ER 30th SEPTEM BER, 1946 :

(instead of 2s. 2d.)

(instead of 2s. 2d.)

(instead of Is. Id.) (instead of Is. 8d.)

(instead of Is. 8d.)

(instead of lOd.)

No fresh cards will be issued. Contributions at the increased rates should be paid on cards now held using the new value Insurance Stamps.

The contribution for persons over pension age (65 men, 60 women) is payable wholly by the Employer.

For particulars of deductions from wages which may be made in the case of employed persons under pension age and for the new rates of Contributions, applicable to special classes of contributors (e.g., Voluntary Contributors, Excepted Persons, etc.), see LEAFLET C.I., obtainable at any Post Office or Employment Exchange.

EMPLOYED MEN

Age 16 & 17 3s. Od.

18 to 65 4s. Od.

65 & over 2s. Od.

EMPLOYED WOMEN

Age 16 & 17 2s. 4d.

18 to 60 3s. 4d.

60 & over Is. 8d.

★ ★

Issued by the Ministry of National Insurance

14

THE MINING MAGAZINE

P ro d u c e r o f th e W o r l d ’s W id e s t Lin e o f M a jo r In d u strial E q u ip m e n t . . . o v e r 1,600 D iffe re n t Pro d u cts th a t F u rth e r G ood Livin g !

Seven fo o t diam eter by fiv e fo o t long A llis-C halm ers B a ll M ill arranged fo r V -belt drive. A llis-C halm ers, world's largest m anufacturers grinding m ills, builds ball m ills in diam eters fro m 3 to io £ f e e t ; in lengths fro m £ to ² times m ill diam eter. A vailable in diaphragm , overflow, peripheral screen, peripheral discharge, batch, and special open-end types. A llis-C halm ers also builds R od M ills, Pebble M ills, B allPeb M ills, and C omPeb M ills fo r yo u to select fro m in getting exactly the right com bination of equipm ent fo r yo u r process.

■" 'A. $

A L L IS - C H A L M E R S M A N U F A C T U R IN G C O M P A N Y offer products of quality and integrity as the builders of the w o rld ’s w idest range of major industrial equipment.

For Allis-Chalm ers builds complete po w er generation, distribution and control equip­

ment— pumps— m otors— V-belt drives— crushing, cem ent and mining equipm ent—

flour— milling, food and chemical processing equipm ent— in all, o ver 1,600 different products that aid industry and fu rth er good living ! Y o u r enquiries for information or literature w ill receive prom pt attention from —

ALLIS-CHALMERS

MANUFACTURING COMPANY,

T O T T O N , S O U T H A M P T O N

T e l e p h o n e : T O T T O N 3 16 1/2 .

15

DORR-OLIVER

w

I N V I ^{j i p m} ; R V I C E

E N G I N E E R S

ABFORD HOUSE - WILTON ROAD - S.W. 1

CONTINUOUS METHODS

FOR CLARIFYING THICKENING CLASSIFYING

COUNTER CURRENT WASHING FLOCCULATING

FILTERING

INCREASINGLY APPLIED

OF CHEMICAL PROCESSES

OVER A WIDE RANGE

16

I ß & Ä f iO B t P ß lG X D lß

G . E . C . F l a m e p r o o f I r o n c l a d S w it c h b o a r d s , c e r t if ie d b y t h e B u x t o n T e s t in g S t a t io n o f t h e M i n i s t r y o f F u e l a n d P o w e r , a r e d e s ig n e d in c o m p o n e n t p a r t s t o e n a b le a c o m p le t e f la m e ­ p r o o f u n it s w it c h b o a r d to b e c o n s t r u c t e d e m ­ p lo y in g a n y g iv e n n u m b e r o f 15, 30 o r 50 a m p . d o u b le - p o le s w it c h f u s e s u p to a t o t a l c a p a c it y o f 200 a m p s .

T h e G . E . C . s p e c i a l is e s in t h e d e s ig n a n d m a n u ­ f a c t u r e o f t h i s v i t a l c la s s o f e q u ip m e n t , a n d w e lc o m e s e n q u ir i e s r e s p e c t in g t h e i n s t a lla t i o n o f a ll f l a m e p r o o f a n d e l e c t r i c a l s a f e t y a p p a r a t u s .

T y p ic a l G .E .C . F la m ep ro o f S w itc h b o a rd (w ith end con­

d u it b o x ) B u xto n T est C e r­

tific a te (G ro u p s I and II).

S . 5 1 3 . F la m ep ro o f Sea lin g G la n d and A rm o u r C lam p.

S . 5 1 0 . 5 am p. F la m ep ro o f S w itc h c e rtifie d by Buxton T est u n der G ro ups I and II.

FU LL I N F O R M A T I O N S E N T P R O M P T L Y O N R E Q U E S T

A dvt. o f The G en era l E le c t r ic C o. L t d .. M a g n e t H o u se. K in g s w a y . London. W .C .2 .

17

18

THE MINING MAGAZINE

D U N L O P R U B B E R C O . L T D . . G E N E R A L R U B B E R G O O D S D I V I S I O N , C A M B R I D G E S T . , M A N C H E S T E R .

LO N D O N : Clerkenwell House, Clerkenwell Green, E.C.I. BIRM INGHAM : Dunlop House. Livery Street, 3 LIV ER PO O L : 24, Cornhill, Park Lane, I. G L A S G O W : 48-60 & 70-78, North Wallace St. C.4.

46 G R G 26A

3—2 19

■DUNLOP

^ DUNLOP Conveyor belt at the M anchester Colliery Company's W orkings.

ROPE

PROBLEMS

gRITISH Ropes Limited offer their services to manufacturers faced with rope problems. These prob­

lems are highly technical: they involve practical knowledge of rope usage only to be gained by the most extensive experience.

For many years British Ropes Limited have made ropes and fittin gs for e v e r y in d u stry throughout the world. Their practical experience is unique.

There is no rope problem to which they are unable to find the answer—and supply the rope.

BRITISH ROPES LIMITED

M A N U F A C T U R E R S O F W I R E R O P E , W I R E , H E M P C O R D A G E & C A N V A S

Head O ffice: D O N C A S T E R , E N G L A N D ______________________________________________________________________BR.20

On the command—

Go!

Air, acid, gas, water, oil— all these and other fluids acknow­

ledge th e m a s te ry of the Saunders 'D iaphragm ' Valve.

On the word ' Flow ’— the fluid goes to its destination unhinder­

ed and without contamination.

On the word * Halt ’ the flow is arrested positively.

Write for explanatory literature with recom­

mendations for your project.

s'NNSl'iftït-' ■

S A U N D E R S tU M K E VALVE CO . LTD

C W M B R A N ■ N E W P O R T • M O N M O U T H S H I R E

20

THE MINING MAGAZINE

Use an

E D G A R

A L L E Y S T A G

B A L T M L L

FOR GRINDING DOWN ORES AND OTHER MATERIALS TO SPECIFIED FINENESSES

Special Features:

# Continuous feed and discharge.

# Simple, solid construction.

# Low upkeep.

# Accessibility o f parts.

W r it e fo r p a m p h le t to :

E D G A R A L E E N &: C O M P A N Y , L T P

I MPERI AL S T E E L W O R K S ! - S H E F F I E L D - 9

★ Also Tube Mills, Crushers, Granulators, etc.

M .M .

3—3 21

IN MODERN MINING )

The greater use of

E X P L O S IV E S POWER )

can help to make good the gaps in man power.

We shall be pleased to give technical service and advice on all blasting problems.

IMPERIAL CHEMICAL INDUSTRIES LTD.

LONDON, S.W.l.

T A K E TH E ROUGH AND THE SMOOTH!

In the recovery of rich minerals from Alluvium there is no short cut.

Good Equipment and hard work there must be. But the better the Equipment, the lighter the work, and in the Lobnitz Alluvial Dredge you have efficiency at its peak. For whole-hearted endeavour under the roughest conditions, smooth, fault­

less working and dependability there is but one name— Lobnitz.

All of their rich experience in every form of Dredging is at your service.

ALLUVIAL DREDGES ^L

^.

55/61, M O O R G A T E L O N D O N

T E L E P H O N E : M O N A R C H 5 I 0 I A S S O C I A T E S

L O B N I T Z and C o m p a n y L t d . , R e n f r e w , S c o t la n d

T A Y L O R W H A R T O N Ir o n an d S t e e l C o m p a n y , H ig h B r id g e , N . J . , U . S . A . Y U B A M a n u fa c tu r in g C o m p a n y , Sa n F r a n c is c o , U . S . A .

22

THE MINING MAGAZINE

In the years that lie ahead, efficiency in Britain's mines,factories and workshops will largely depend upon the design and q u a lity of the

p l a n t a n d / machinery used.

Robey ofLincoln who have been making industrial plant for nearly a century will, by keeping their manufactures up-to- date, continue to contribute to in- J dustrial efficiency.

OBEY 8' CO LTO. LINCOLN, London Offices: Commonwealth Bank Chambers.Qtd Jewry E.C.2.

ONE INSTRUMENT m easures:—

C u r r e n t , A . C . an d D . C . (0 t o 10 a m p s .) V o lt a g e , A . C . and D . C . (0 t o 1000 v .) R e s is ta n c e (u p t o 4 0 m e g o h m s ) C a p a c it y (0 t o 20 m fd s.) A u d io - f r e q u e n c y

P o w e r O u t p u t (0 t o 2 w a t ts ) D e c ib e ls ( — 25 D b . t o + 16 D b .)

The AvoMeter is one of a useful range of “ Avo ” electrical testing instruments which are maintaining the

“ Avo ” reputation for an unexcelled standard of accuracy and depend­

ability—in fact, a standard by which other instruments are judged.

S ole P ro p rie to rs a n d M a n u fa c t u r e r s:—

A u t o m a t i c C o i l W i n d e r & E l e c t r i c a l E q u i p m e n t

-I- H E Model 7 U niversal AvoM eter is the w orld’s m ost widely used com bination electrical m easuring instrum ent. It pro­

vides 50 ranges of readings on a 5-inch scale and is guaranteed accurate to B.S.

first-grade lim its on D.C. and A.C. from 25 c/s to 2 K c/s. It is self-contained, com ­ pact and portable, sim ple to operate, and alm ost im possible to dam age electrically.

It is protected by an autom atic cut-out against dam age through severe overload, and is provided w ith autom atic com ­ pensation for variations in am bient tem perature.

C o . L t d . , W i n d e r H o u s e , D o u g la s S t . , L o n d o n , S . W . I Phone V icto ria 3 4 0 4 - 8

”1° V'b-'lV lO i ° °

C m IT U OdJnMLo and

J rll I H Cxca.Atàfaci

T H O M A S SM IT H & S O N S (Rodley) LTD ., R O D L E Y , L EE D S Specialists in the design and manufacture of Cranes and Excavators

24

THE MINING MAGAZINE

id Field E ngineers M E T A L L I C S A N D

N O N - M E T A L L I C S

R E A G E N T S

Aero Brand Cyanide . . . Aerofloat"

O W Flo ta tio n R eag en ts . . . X a n th a te s, ^ M A ll Grades, and other M ining Chemicals.

* /

• f - - —

■ The Fagergren Flotation Machine . . . (Mechanical)

> I The Steffensen Flo tatio n M a ch in e (Free A ir) H I

i I HEAVY-MEDIA SEPARATION PROCESSES

Sink-Float Processes using Ferrous or Non-Ferrous

\ Media for Mineral Beneficiation and Coal Cleaning.

\ T E C H N I C A L s e r v i c e The Cyanamid Mineral Dressing Laboratory 4

A N T H R A C I T E A N D B I T U M I N O U S C O A L

\NAMID PRODUCTS, Ltd.

BERKHAMSTED, HERTS.

3—4 25

HUDSON CAST STEEL WHEELS

MADE

OUR OWN STEEL FO U N DRY

Also Makers of

COMPLETE WHEELS AND AXLES

Quick Deliveries

ROBERT HUDSON LTD- LEEDS

L O N D O N O F F I C E : 21, Tothill Street, S.W . I. ’Phone: W hitehall 7127.

D E N V E R E Q U IP M E N T C O ., L TdT ^ L

S a lis b u ry House. London W a ll. L O N D O N , E .C . 2 ■ T e l.—M O N a rc h 3 7 5 0 . C a b le— "D e c o l o n L o n d o n . D E N V E R —T O R O N T O —J O H A N N E S B U R G — N E W Y O R K

DENVER

HYDROCLASSIFIER

D

You can now handle sizes from minus 100 mesh to Micron size in one unit.

S u g g e s t e d U s e s :—

D e s l i m i n g :— C o a l, B u i l d i n g S a n d , e tc . S iz i n g :— C e m e n t , B r i c k s lip , W e l l d r il lin g m u d , H e a v y m e d ia , G o l d c o n c e n t r a t e s f o r c y a n id a t io n , e tc .

W r it e fo r le a fle t N o . C 4 A / B .

26

THE MINING MAGAZINE

POWER VANE COAL C U T T E R

THE PERFECTED COMBINATION

THDS. FIRTH JOHN B R O W N LTD ^SHEFFIELD

27

STANDARD DUMPY LEVEL

\\*i _( -

•te iot u r^%e rMtV

¿WeS Y\Ss' C* «A e-Q'VJ

vsu»

SlNc-p H A V p r , > 8 s ? F

C A M B E R W E L L , L O N D O N , S . E . 5

E S T D . 1857,

BUILDERS OF EUROPE'S LARGEST EXCAVATORS

Sizes

I

SH O V ELS T R E N C H E R S SKIM M ERS D R A G L IN E S G R A BS

r^ p rrra ^ w/50 W a lk in g D r a g lin e s tr ip p in g o v e r­

b u rd e n .

R A N S O M E S & R A P I E R , L T D . . I P S W I C H & L O N D O N . E N G L A N D

THE MINING MAGAZINE

I

I

*## S IN K A N D F L O A T P L A N T A T B U N K E R H I L L A N D S U L L I V A N M I N I N G A N D C O N C E N T R A T I N G C O M P A N Y O F K E L L O G G , I D A H O , F O R T H E T R E A T M E N T O F 1,400 T O N S O F L E A D O R E PER D A Y .

29

LIMITED ROPEWAYS

V IE W O F M O N O C A B L E .R O P E W A Y I N B O L I V I A L E N G T H — 8,000 metres

Unbroken Experience and Progress in all S y ste m s o f

AERIAL ROPEWAYS

Telephone No. : Clerkenwell 1442/3. Telegrams: Ropeways, London.

1891-1946

W e have completed

5 5 YEARS

L O N D O N , E .C .2 62, L O N D O N

W A L L F O U N D E D I B 9 I

■SO

Makers of Q u ality Steels and Tools since 1776

For continuity of output and economy in production cost, specify “ C O L O R A D O ” when next ordering mining steel or tools.

SANDERSON BROS fr NEWBOULD L'J?

NEWHALL ROAD

SHEFFIELD

THE MINING MAGAZINE

LOWDEN DRYERS

T h e d rying o f flotation co n ce ntrate s was an un­

solved p rob lem p rio r to th e d e velo p m e n t o f the Lo w d e n D ry e r and the fact th a t re p e a t o rd e rs have been re ceived fro m pleased users p roves th a t th e m ach in e c o m p le te ly m eets re q u ire m e n ts . I t is w ith o u t dust losses.

P a rt o f in sta lla tio n o f 4 Low den D r y e rs d e a lin g w ith Z in c C o n c e n tra te s.

an ideal d ry e r fo r hand ling fine, s tic k y m a te ria ls

Low den D ry e r e re c te d an d rea d y fo r o pera tio n .

C o llie r y P la n t.

★

M e ta llife ro u s M in in g P la n t.

★ G a s , C o k e and

C h e m ic a l P la n t.

★

S tru c tu ra l S te e lw o rk .

HEAD, WRIGHTSONtCL”

S T O C K T O N FO R G E , S T O C K T O N - O N - T E E S

32

Quasi-Arc Welding Service is based on a most thorough-going organisation . its extent is not generally realised by the average buyer or user. This extensive and up-to-the-minute organisation produces the world’s finest electrodes and weld­

ing equipment—conducts its. own training schools in three centres—provides unrivalled technical bureaux — is represented throughout the world.

Wherever you are and whatever your needs Quasi-Arc Service is there to assist.

X-2

DIAMOND ^{c o r e} DRILL

U"” u°S d“ i!' X-! Drill m?„„Ied on ,rjme for

. , surface drilling

C o »-es ¡n. to | in n l , i n S D e p th 300 ft.

W e ig h t with m otor 500 lb. A“ t°matic pressure controlled screw feed.

Drive : Compressed air'.

Pneumatic rod extractor.

C R A ELIU S C O M PA N Y i .-

* 2 , C L A R G E S S T R F F T i

T E L E P H O N E : E E T > L O N D O N , W . |

E L E G R A M S : ^ R O S V E N O R , 3 7 8 o T H E S W E D IS H D IA M A g e " tS #° r A E U U S * l O N D O N

ROCK DRILL1Ng C OM pAN y

o n t h e N.E. m a p Situated between the Cities of Durham and Newcastle-on-Tyne, Birtley lies in the centre of the vast industrial area bordered by the Tyne and Tees. It is excellently served by road and rail. This easy accessibility to the great manufac­

turing and shipbuilding centres of the North East has been a factor of great importance in the steady development of the Birtley Company.

Its varied products and activities find

a ready outlet among firms of world repute in widely separated districts up and down the country. Study the list of activities and products given here and contact Birtley if you need help.

Birtley is nearer than you may think.

W E L D I N G S & F A B R I C A T I O N W O R K S H E E T M E T A L & P L A T E W O R K P R E C I S I O N - M A C H I N E D S M A L L P A R T S & C O M P O N E N T S P L A S T I C M O U L D S & M A C H I N E R Y M A N U F A C T U R E C O M P L E T E C O A L C L E A N I N G & M A T E R I A L S H A N D L I N G P L A N T In th e n e ar fu tu re S T O V E &

V I T R E O U S E N A M E L L I N G

T H E B I R T L E Y C O M P A N Y L T D . , B I R T L E Y , C O . D U R H A M

THE MINING MAGAZINE

DREDGE PARTS BY YUBA

For almost 40 years Y U B A has pioneered the use of alloy steels for vital parts in alluvial dredge construction and to-day leads in adopting for dredge use proved m etallurgical developm ents to ensure long life under arduous operating conditions.

O n any dredge excessive w ear or breakage of bucket pins, tu m b ler w earing plates, screen plates, ladder rollers, etc., is elim inated because Y U B A ’S w o rld w ide experience has shown how to lengthen the life of such dredge parts.

W h y take costly risks ? W h e n you buy Y U B A spares you pro tect yo u r investm ent.

You profit from Y U B A ’S specialised experience in servicing the w o r ld ’s most successful operators of alluvial dredges.

vubr mnnuFncxuRinc to.

351 C a l i f o r n i a S t., S a n F r a n c is c o , C a l if o r n ia A G E N T S :

n i l U V I R I DREDGES 1TD.

5 5 -6 1 M o o r g a t t , L o n d o n E. C 2

C A B L E S — Y ub i

T e m p o r a r y A d d r e s s :— R e n f r e w , S c o t la n d .

" Y " _ROPE

DRIVES

FR A N K

WIGGLESWORTH

ENGINEERS * co LTD' S H I P L E Y Y O R K S

Phone : S H IP L E Y 1666/7/8 T E X R O P E D R I V E R ” Bail Mill with G ra m s ; C|_ U T C H S H | P L E Y

Grinding and classifying coal 98-6%-100 mesh.

f o . R E L I A B I L I T Y

S P E C IF Y

W IG G LESW O R TH — " T E X R O P E 1' V ^{D RIVES}

36

THE MIXING MAGAZINE

m o t « t h o s s ««»BW« costs

? 8 0 0 U C T o F T H E

m v z rn m orn)

B R O O K H O U S E • P A R K L A N E * L O N D O N W. l

T C L £ P H / J H c : « » Y f i l B 3 0 6 7 a T C L C C P A H S - N 0 8 0 B E « 0. H U D l i Y . L O N O O I H e a d O f f i c e j a n d W o r k s : M I L W A U K E E • W I S C O N S I N ■ U • S - A

37

HIGH EFFICIEN CY INDUSTRIAL PLANT

WESTGARTH B R O W N B O V E R I . LTD.

H A R T L E P O O L

M A G N ET IC E Q U IP M EN T BY » R A P ID ”

F o r th e sep aratio n o f . : . feeb ly m ag n etic ores such as

W O L F R A M , T I N , T A N T A L I T E , M O N A Z I T E , e t c .

specify

O H Q

0 Phenom enal Belt Speeds

£ High efficiency

£ Sim ple adjustm ent

0 Available for belt drive o r e lectric m otors

For tw o minerals of differ­

ent magnetic perm eability

w e offer the

“ R A P I D O R E ”

T h e RAPID MAGNETTING MACHINE COMPANY L IM IT E D ,

Works: Magnet Works. Lombard St., Birmingham. 12 Phone:Victoria H27-8 (TwoLines) drams: Borings.Birmingham.l2

38

THE MINING MAGAZINE

INTERNATIONAL (g ) COMBUSTION L™

N I N E T E E N W O B U R N P L A C E • L O N D O N • W . C . I . - W O R K S : D E R B Y ________________________________________________________________

For classifying coarse rock with speed and accuracy, specify the TY-ROCK screen. Its two outstanding features are a POSITIVE CIRCLE THROW with absolute balance and LOW OPERATING COSTS. This balanced operation allows high speeds with no destructive vibration transmitted to frame­

work or foundations. Wherever high capacity and low operating costs are prime considerations, specify Ty - rock screens.

T h e T e c h n ic a l S t a f f o f In te rn a tio n a l C om b u stion L td . a re a lw a y s re a d y to b rin g th e ir e x c e p tio n a l e x p e r ie n c e to any sc re e n in g p ro b le m .

P H O T O P R O O F The photo shows the T Y -R O C K screen vibrating at speed. So perfectly is this vibration IN S U L A T E D from the base o f the machine that two coins can be seen balanced there on the edge.

N ote also the white circles in black squares. Each circle is really a white painted spot, revolving in its course.

39

D R I L L S T E E L

‘HECLAI ⁸

H O L L O W O R S O L I D

N o . 3 0 8 8

H A D F I E L D S LTD., E A S T H E C L A W O R K S , S H E F F I E L D , E N G L A N D . C A T A L O G U E No. 4 5 7 S E N T ON R E Q U E S T .

The Mining Magazine

P u b l i s h e d on the 15th of each month at S a l i s b u r y H o u s e , L ô n d o n , E.C. 2, for M i n i n g P u b l i c a t i o n s , L t d .

Editor : F. H i g h a m , A.R.S.M., M .Sc., Assoc.Inst.M.M.

Manager : S t . J . R. C. S h e p h e r d , A.R.S.M ., D .I.C., F.G.S. Chairman : H. E. F e r n , O.B.E., J .P . T elep h o n e : M O N arch 9 4 1 6. T eleg rap h ic A ddress : Oligoclase. C odes : M cN eill, b o th E d itio n s, & B entley.

Br a n c h Of f ic e, N ew Y ork : A m er. In st. M . & M .E . Su b s c r ip t io n{ u .S .A ^ IT p “ ? a n n im T Id u d in fp o s ta g e .

Vol. LXXV. No. 3. LONDON, SEPTEMBER, 1946.

* 5

( POLITECHNIKI!

C O N T E N T S

Ed it o r ia l

N otes... 138

Harrison’s “ Examination, Boring, and Valuation of Alluvial and Kindred Ore Deposits *' ; Control of Rare Metals ; Mercury Control Revoked ; Skinner’s

“ Oil and Petroleum Year Book’’ ; International Tin Conference; Nuffield Scholarships; National Coal Board ; Mineral Resources of C hina;

Germanium.

Rand Native Labour ... 139

A review of the present situation.

Copper in the Transvaal ... 140

Attention is called to a recent report of the South African Geological Survey.

Mo n t h l y Re v ie w ... 141 Ne w Co m p a n ie s Re g is t e r e d... 144 Div id e n d s De c l a r e d... 144 Ar t ic l e s

Drilling with Counterflush Continuous Coring ... C. J . Esseling

A system adapted to oilfield prospecting.

Venezuela : The Venezuelan Andes and the Coastal and Interior Ranges *

John C. Davey 149

(Concluded from the August issue, p. 87)

The Flow of Pulp through Spigots

R. T. Hancock

Expanding an equation previously proposed.

Estimating Welding Costs on Castings H. Seymour 162

A survey for the maintenance staff.

Or e Dr e s s in g No t e s... 164

Particle Shapes; Pumping; Handling the Heavy

En g in e e r in g Log ...' ...

167

Ne w s Le t t e r s

Vancouver... 170

Mine Labour ; Portland Canal; Alberni ; Cariboo ; Omineca ; Similkameen ; Osoyoos ; Slocan.

Toronto ... 173

Gold Production ; Porcupine ; Kirkland Lake ; North- Western Ontario ; Manitoba ; Quebec.

Melbourne ... 175

State Assistance to M ining; Activity at Tennant Creek ; Tin Mining at Torington ; Operations at Kalgoorlie ; King Island Scheelite ; Mining in Victoria ; Mining in New Guinea ; Mount Morgan.

British Guiana ... 177

Pe r s o n a l...

178

Tr a d e Pa r a g r a p h s...

179

Holman Drilrigs... 181 Me t a l Ma r k e t s ...

183

St a t is t ic s o f Pr o d u c t io n...

185

Pr ic e s o f Ch e m ic a l s ...

187

Sh a r e Qu o t a t io n s...

188

Min in g Dig e s t

Rockburst Control at Lake Shore W. T. Robson Future Mineral Resources .. W. E. Wrather An Alaskan Tin Mine H. E. Heide Magnetometer W ork on the Canadian Shield

T. Koulomzine Crushing Underground in New South Wales

189196 197 201199 Re c e n t Pa t e n t s Pu b l is h e d ... 202 Ne w Bo o k s, Pa m p h l e t s, e t c... 202 Se l e c t e d In d e xf

to Cu r r e n t Lit e r a t u r e 203

3—5 137

A

USEFUL new work has been published during the past month by Mining Publications, Ltd., proprietors of

The author is H. L. H. Harrison and his book is entitled “ Examination, Boring, and Valuation of Alluvial and Kindred Ore Deposits.” Intended primarily for the man unfamiliar with alluvial testing procedure it also makes a serious contribu­

tion to the literature of the subject, par­

ticularly in its approach to the question of standardizing boring, sampling, and valua­

tion methods in placer fields. The precise interpretation of boring results assumes greater and greater importance as lower- grade areas enter the ore-held class and a book of this character should find a welcome from engineers concerned with such work.

I

NCLUDED in a recent control order1 made by the Board of Trade are ores and concentrates of thorium and uranium, as well as cadmium and cadmium compounds.

B

Y virtue of the Control of Mercury (No. 12) (Revocation) Order, 1946, which came into force on August 23, the statutory maximum price control of mercury

and its compounds was removed.

T

HE 1946 edition of Skinner’s “ Oil and Petroleum Year Book” 2 made its appearance last month. This standard work, now in its 37th year of issue, contains concise and up-to-date particulars regarding 566 companies engaged in all branches of the oil industry.

I

T is officially announced by the Ministry of Supply that an International Tin Conference has been called by the United Kingdom Government in consultation with the Governments of the United States, Bolivia, Belgium, and the Netherlands Countries. Invitations are to be sent to each of these countries and also to China, France, Siam, and the U.S.S.R. The conference is expected to open on October 8.

1 Export of Goods (Control) .(No. 3) Order, 1946.

S.R. and O., 1946, No. 1473. London : H.M.

Stationery Office. Price Id.

2 London : W alter E. Skinner. Price 15 s.

LSEWHERE in this issue an advertise­

ment gives particulars of a new group of fellowships and scholarships for the advancement of extraction metallurgy about to be established by the Nuffield Foundation.

Travelling fellowships and post-graduate scholarships, as well as vacation scholarships, are offered to graduates, staff, and students at approved centres of learning. They are open to all citizens of the Commonwealth and should help to keep younger metallurgists in tune with advancements in the art in other countries.

A

S a first move in its attempt to recon­

struct the British coal industry the National Coal Board has initiated a series of conferences to be held each week-end throughout the current month and October at various centres in the coalfields. At these meetings speakers “ will urge managers and men to pledge themselves to work together, in full recognition of their joint responsibility for the well-being of the industry under the new ownership, to establish the highest possible degree of safety, efficiency, and pro­

duction, to introduce a new industrial out­

look, and to secure friendly discipline in the industry.”

B

ASED on a detailed report prepared while on the staff of the United States Geological Survey V. C. Juan contributes a study of the “ Mineral Resources of China ” to Economic Geology for June-July. This shows that China, with immense coal and moderate iron resources is potentially an industrial nation. The country has consider­

able oil-shale reserves, but petroleum pro­

duction is not likely to become important for some time, practically all China’s oilfields being largely undeveloped. Manganese re­

sources in the country appear sufficient to meet all requirements and it is rich in gold, although poor in silver. Large exportable surpluses of antimony, tungsten, tin, mag­

nesite, talc, clay, fluorite, mercury, and arsenic appear probable. With adequate water power it is likely that an important aluminium industry can be based on extensive bauxite deposits, while it seems that adequate copper, lead, and zinc will be found for domestic needs.

G

ERMANIUM, now being produced in

America as a by-product of the zinc

industry, is closely allied to silica in physical

SEPTEMBER, 1946 139 and chemical properties. A paper recently

issued in the United States 1 suggests that the technological application of germanium has been hampered by its association with silicon and points out that although the element is now being produced in commercial quantities it is still largely being used experi­

mentally. Application depends on the developments suggested by recent work. It is stated that traces of germanium had been noted in zinc sulphide ores of the Tri-State district for many years, but that no effort was made to recover the metal until about five years ago. By spectroscopic analyses germanium was found to be concentrated in the cadmium fume produced in sintering the zinc concentrates.

Rand Native Labour

The South African gold-mining industry, beginning slowly to recover from the effects of'war-time conditions, seems likely to play a greater part than ever in the Union economy. There is, indeed, a general expecta­

tion that the industry’s position is finding increasing recognition from the Union Govern­

ment, particularly as its expansion into the Free State should mean increased revenue, expanding employment, and an extension of ancillary industries into new areas. Although taxation still weighs heavily on mining enterprise in South Africa it is not likely to affect the industry so much as the continued shortage of labour—particularly native labour. With the establishment and growth of secondary industries, all of them, be it noted, dependent on gold-mining for their well-being, there has been an increased de­

mand for labour in the Union and large numbers of natives have left mining for other work. Mining Survey, a new periodical review published by the Transvaal Chamber of Mines, in its first number 2 describes native labour as the key to expansion. It points out that in 1941, when 67,255,450 tons of ore was milled by the Rand gold mines, the average number of natives employed was 367,400. In 1945 this number had fallen to 306,600 and the tons of ore treated to 58,897,600. The gold revenues for these two years were £116,978,499 and £101,847,382

1 Jaffee, R. I., M cM ullen, E. W„ and G onser, B. W. United States Electrochemical Society, Preprint 89-18.

2 London : A. Moir and Co., London Secretaries, Transvaal Chamber of Mines.

respectively. In the past the mines have had to import labour from other parts of Africa and now that, with the likelihood of fresh demands from the developing areas in the Orange Free State, the need is becoming greater steps will have to be taken once again to find fresh sources of supply. So much in South Africa depends on a healthy gold-mining industry that the Government must soon turn its attention to the urgent need in respect of native labour, particularly as the mines must work hard to make good by increased development the ore reserves so heavily drawn upon during the war.

As in so many other parts of the world the labour shortage in the Union has led to unrest. Earlier this year a dispute within the European mineworkers’ union led to a virtual cessation of operations throughout the industry for some days and subsequent negotiations between the union and the Transvaal Chamber of Mines resulted last month in fresh wage increases estimated as likely to cost the mining companies some

£1,000,000 more annually. In such an atmosphere the Native Mineworkers’ Union was unlikely to remain inactive and in the middle of August strike action on its part resulted in a partial stoppage of the industry.

The strike was speedily settled, but not before outputs at certain properties had been seriously affected. While labour is scarce the unrest is likely to remain and there is greater need than ever to take every possible step to increase the native labour supply.

In respect of the situation reviewed it is satisfactory to record that the native labour position was regarded with a certain amount of optimism by Mr. C. S. McLean, the retiring president, at the annual meeting of the Transvaal Chamber earlier this year.

Mr. McLean said that during 1945 the average labour strength of the industry improved by no less than 10,000 natives.

The most pleasing feature, he said, was the

upward trend in recruiting results from the

Union and High Commission Territories

where, for some years, recruiting had been

adversely affected by factors arising out of

war conditions. Earlier in 1945, Mr. McLean

said, there was a heavy wastage of time-

expired Portuguese natives and, in spite of a

satisfactory recruiting output, fresh arrivals

failed to make up the consequent reduction

by the end of the year. The results from

tropical areas continued to show a steady

improvement with a net gain of 4,000

natives during the year. In December