The Electrician : the oldest weekly illustrated journal of electrical engineering, industry, science and finance, Vol. 139, No. 15 (3617)

T H E " " 1 %

E L E C T R I C I A N

T H E T E C H N IC A L N E

G o o d L ig h t is a B u s i n e s s A sse t

The war years taught business men and industrialists the economic value of correct lighting. If you would like expert advice on your present lighting, or if you have any lighting problems, you are invited to write to BTH Lighting Advisory Service, Bridle Path, Watford. Tel.: Watford 7701j8

^ L A M P S

’ B 1

iTiH

FITTINGS

M.4149

The British Thomson-Houston Co. Ltd., Crown House, Aldwy ch, London, W .C .2

GEORGE

FORRE

Very attractive Wall Bracket available in same finishes as above.

This bracket is usually used in conjunction with Model G .3I9I Ceiling Fitting.

OSBORNE RD., ACTON, LONDON, W.3

T E L E P H O N E : A C O R N 5 0 8 1 (5 lines) T E L E G R A M S : G E F S O L , E A L U X , L O N D O N

2 J 7 3

G.2720. Indirect Lighting G.2736. An attractive fitting G.2734. Indirect Pendant in Pendant in Crackled Cream, in Cream and Bronze. Glass- Green and Bronze enamel, with Green Suspension Rod. ware in Peach or Champagne. 16" diameter

A LL THE ABOVE FIT T IN G S ARE DESIGNED TO CA R RY 100jl50W LAM P.

A v a i l a b l e in alternative finishes of C hrom ium - Plated, Coinage Bronze or Ivory Stoved enamel with Satin obscured Glassware.

G.3I92 G .3 I9 I

Fittings complete with lampholders. Arranged for standard 2 " centres fixing.

NOTE. Stepped or flat-bottomed glass as illustrated supplied to either model.

These fittings are suitable for 60/

100 W Lamp. Stove enamelled reflector interior. Glass 10" dia.

Overall dia. 12 \ " . Overall depth sr -

TH E E L E C T R IC IA N io O C T O B E R 1947

1037

T h e s w it c h e s o f th e m o d e r n in t e r ­ c o m m u n ic a t io n lo u d s p e a k e r t e le p h o n e m u s t be ca p a b le o f w it h s t a n d in g c o n ­ sta n t u se in t h e b u s y office o f to -d a y .

A . B . M e ta l P r o d u c t s e n s u r e th e d e p e n d a b ilit y o f t h e ir s w it c h e s b y m e a n s o f lo w c o n t a c t re sista n c e , se lf-c le a n in g c o n ta c ts an d th e “ F in g e r T o u c h O p e r a t io n ” e m b o d ie d in t h e ir d e sig n .

T h e d is c e r n in g m a n u fa c tu re r w ill realise, t h e re fo re , th a t w h e n he fits an A . B . L L o r L A T y p e it is an a s s u ra n c e o f d e p e n d a b ilit y — a c o n t r a c t f o r e a sy c o n ta ct.

All A.B. OAK Switches are M anufactured under Patent N os. 478391, 478392

P R O D U C T S L!

O C T O B ER 1947 TH E E L E C T R IC IA N

NewE ra

GREAT SOUTH W EST ROAD, FELTHAM , M IDDX.

Telephones : Hounslow 6256. Feltham 2865.

10

1038

Switchcraft is the M.E.M. method of design and manufac­

ture which brings you a better product at a lower price.

W rite now for copies of the new M.E.M catalogues.

All done by

switchcraft

B r a n c h e s in L o n d o n a n d M a n c h e s t e r

TH E E L E C T R IC IA N io O C T O B E R 1947

1039

1

B T H [

¹u * v j . l v . 1 .1.1 S L.' M 1 I I I I. u -I

^R

ri 1

^{U G B Y}

i o O C T O B ER 1947 TH E E L E C T R IC IA N

h HP to 1 HP.

The m ost

p v jo id a iim

thecm rtu/

W h a t e v e r t h e c o n d it io n s o f s e r v ic e o r t y p e o f d r iv e , t h e r e is a B T H M o t o r a v a il­

a b le f o r t h e jo b .

• •

O V E R 5 0 Y E A R S ’ M A N U FA C TU R IN G

E X P E R IE N C E B E H IN D T H E S E

M O T O R S

1040

J E N G T H S of 132 k V oil-filled cable taken up in Lon d o n due to route repair w o rk , after 15 years service, have been subjected to the full tests applied to new cable and found to give results identical w ith the original tests.

O IL F I L L E D SU PER TENSION CABLES

33 k V to 330

I i r e l u - G e n e r a L

M A N U F A C T U R E R S OF E V E R Y K I N D 0 F E L E C T R I C C A B L E

Pirelli-General Cable W o rks L td S o u t h a m p t o n .

TH E E L E C T R IC IA N 10 O CTO BER 1 9 4 7

1041

10 O C TO BER I 9f 7 TH E E L E C T R IC IA N

REYROLLE HEBBURN CO.DURHAM

N e w ly d e s ig n e d f la m e p r o o f c o n ­ ta c to r to con trol in creased power de m and d u e t o concentrated

g a r

V v V 150 A M P S 625/4-00 VOLT

3-d u a c c c n - r v r i c 625/4-00 VOLTS 3-PH flSE 50-CYCLE ||||||||

To control 75/150 hp machines

r o x 1* 0 ® *

P R E S S TO O LS P R E S S I N G S M O U L D S A N D J I G S

o n «

T R A N W A Y P A T H

' { f t V . ^ irim

MITCHAM S U R

T/i n n r r m F R t o a j

TH E E L E C T R IC IA N 1042

W ire s, from thickest to m edium gauge, are d ra w n ] in one operation o n all- B ritish high speed ma­

chines using T ungsten C arb id e and D iam on d dies, givin g perfect finish and gauge to meet the m ost exacting specifications re­

q uired to-day.

J

© E.38

47, Victoria Street,

W e s t m i n s t e r , L o n d o n , S . W . I Telephone : A b b e y 2771 (Pte. Br. Ex.)

W o r k s : Enfield, M id dlesex

' W r i t e f o r f u l l d e t a i l s t o :

E K C O - E N S I G N E L E C T R IC m

S O U T H E R N S A L E S O F F IC E W E S T E R N S A L E S O F F IC E N O R T H E R N S A L E S G F F IC E M ID L A N D S A L E S O F F IC E

5 , V i g o S t r e e t , L o n d o n , W . 1 5 0 , B r i d g e S t r e e t , C a r d i f f K e n t S t r e e t W o r k s , P r e s t o n , L a n c s 4 0 & 4 2 , S u m m e r Row, B i r m i n g h a m

io O C T O B E R 1947 TH E E L E C T R IC IA N

l i r E N G I N E E R I N G CO., V ( N O T T I N G H A M ) LTD.

H A S L A M ST., C A S T L E B O U L E V A R D ,

to«- N O T T I N G H A M j

• P H O N E : N O T T IN G H A M 46068 (3 Lines) 'G R A M S : C A P ST A N . N O T T IN G H A M

O N A IR M IN IST R Y . A D M IR A L T Y A N D W A R O FFICE LISTS

R E P E T I T I O N W O R K IN A L L M E T A L S

O p e n m a r i n e - t y p e s w it c h b o a r d c o n tr o llin g th r e e 200 k W g e n e r a t o r s a n d c ir c u its a n d i n c o r p o r a tin g D o rm a n XL a ir - b r e a k c i r c u i t b r e a k e r s a n d D o rm a n " F " ty p e s w itc h e s a s i n s ta lle d o n th e L .N .E. R a ilw a y 's n e w c a r g o li n e r S.S. A rn h e m

(Jo h n B ro w n & C o ., L td.)

D O R M A N & S M IT H LTD. • M A N C H E S T E R • L O N D O N • G L A S G O W

E2I47

TH E E L E C T R IC IA N 10 O CTO BER 1947

1045

W i r T T K S I N G L E - P H A S E

t r l t N ^ A L L - I N S U L A T E D

ELECTRICITY METERS

T Y P E 21

APPROVED

B Y THI/.-y-V:'-':

E L E C T R I C I T Y C O M M I S S I O N E R S

sC&MP|Y WlTif AS.S. No. 37-1937

jo O C TO B ER 1947 THE E L E C T R IC IA N

1046

VAR I AC

§ R E G U i.A T IN G

«TRANSFORMERS’

£ •& * * *

The Type 50 B Variac, handling 7 k V A at 230 V in. represents a valuable addition to tbe Variac range, and will find many applications in industry.

50 B 7 k V A Input 230 V (tap at 115 V), output 0-230 or 0-270V. Rated current 20 amps. Max. 31 amps.

m

1

P

À

«Ü:.s ■■■}

§ §

P

t l Excellent deliveries can be arranged. M ost types are In stock. Other Variac types range from 165 watts to 7 kW. W rite for bulletin 424 E and lis t y A R 747 for complete data.

WHlKifflMlJi

ELECTRICAL AND RADIO LABORATORY APPARATUS ETC. Ii

180 T o tte n h a m C o u r t R oad, L o n d o n , W . I a n d 76 , O l d h a t I S t r e e t , L i v e r p o o l , L a nc s .

The comprehensiveness, the quality, and the reliability of the Lundberg range of switches and accessories is sufficiently proved by the striking fact that throughout the war the Admiralty, the War Office, and the Air Ministry were able to order the switches they needed simply by our list numbers. Not a moment was lost on designs or experiments—not merely on accessories for everyday requirements, but also for the most specialised and compli­

cated of apparatus, from radar sets to degaussing gear. Today the Lundberg capacity is fully taken up with priority requirements, but the time will come again when you can order your exact needs from our catalogue. In the meanwhile we do our best to ensure equitable distribution of what is available

L U N D B E R G

■ M R E G ? T R A D E M A R K

IE K T R IK

A © C O M P A N Y

\ P Lundberg & Sons Ltd. (Established 1882’

491-493 Liverpool Road London N7

TH E E L E C T R IC IA N io O C TO BER 1947

S e le c te d h a rd e n e d steel c h u c k p a rts and c a rb o n

steel sp in d le .

S u p p lie d w it h t h r e e bits.

A p p r o x im a t e W e i g h t

\\

^lbs.

RATCHET S C R E W D R I V E R

E a sie r and fa ste r w o r k w it h o u t d ise n g a g in g .

A d ju s t a b le f o r f o r w a r d and re v e rs e action.

H. & D. C H U R C H IL L LTD.

W h o le s a le a n d E x p o r t D is tr ib u to r s

W A L N U T T R E E W A L K , K E N N I N G T O N , L O N D O N , S.E.I I

A lso at B I R M I N G H A M , M A N C H E S T E R , G L A S G O W and N E W C A S T L E

io O C T O B E R 1947 TH E E L E C T R IC IA N

iinuiiiiini

1048

B —• ™ d ¹

it’s a hard life for the m esent Thousands of tr are m0st weakness, were, m ™ w here work is ^ * Blectrical Storage farms rely o n Exide ^ by The C u a n s p o r t . Where

severe you will fin ^ trams and ‘ African

Company ^ d o m in a te c ^ ^ ^ sarne. on _ reliability is « 0 ^ r f the King’s Flight,

i R° y a lChirride Exide or Exide-Ironclad p ^ 0RlDE e i e c t . . « u

1 ^ embodied the experience gamed U H « »

m f i f t y ■ — near M a n c h e s t e r

TH E E L E C T R IC IA N 10 O C TO BER 1947

R E O R G Ä N I S Ä T I O N

1049

W ith reorganisation in progress in many industries to step up production and attain our E X P O R T T A R G E T S , reliable S W IT C H G E A R will be required to assist in the manufacture of countless products of which the world is in need.

“ F.P.” Switchgear is G U A R A N T E E D up to its rating.

E . H . T .

FERGUSON. P A IL IN L IM IT E D

M A N C H E S T E R , 11 j

phone . D R O Y L S D E N 1301 (8 lines)

m

| E N G L A N D

L O N D O N : Temple Bar 8711/2

10 O C TO B ER 1947 TH E E L E C T R IC IA N

1050

TH E E L E C T R IC IA N 10 O CTO BER 1947

ELECTRICAL APPARATUS ACCESSORIES Ar

t f ^ A G R O ^

W H O L E S A L E &

E X P O R T O N L Y

HE ELECTRICIAN—10 October, 1947

P A P E R

i s ^{t h e} l i v i n g

b r e a t h o f ~

F R E E D O M , W i t h o u t i t I D E A S p e r i s h a n d l i f e i t s e l f i s s t l f l e c L F o r t a c k . o f i t t h e l u n g s o f I n d u s t r y s u f f o c a t e .

W e w h o m a k e p a p e r a r e

p r o u d o f t h e c r a f t s m a n ' s h i p w h i c h h a s g u i d e d t h e a r t ^{o f t h e} P a p e r M a k e r : W e s h o u l d l i k e y o u t o k n o w m o r e ^o f t h i s s k t l L

a n d t o g l i m p s e i n t o o u r “ b a c k r o o m ! ’ *

\ & 0 9

'/faiu/

EV E R

W e a r e d e s i g n i n g a g a l l e r y o f

T a p e r P o r t r a i t s r a n g i n g o v e r t h e w h o le s t o r y o f p a p e r m a k i n g b e g i n n i n g w it h a s e r i e s s h o w i n g s o m e o f t h e s o u r c e s o f o u r f i b r o u s r a w m a t e r i a l s .

S C O T L A N D L O N D O N BIRMINGHAM M A N C H E S T E R

Auchmul-y Ci Rofhzs Paper Mills I Tudor St,E.C4. 116 Colmore Row 372 Corn Exchange Buildings

Markinch, Fife CorporaHon Street-

TH E P ION EE RS O F T W IN -W IR E P A P E R S FO R P R IN T E R S

1052

Q . W h y is it that in a so-called selle rs’ m arket some lines of clocks hang fire ?

A . Because buyers still discriminate and do their best to get the best.

Q . W h y is it that Sm iths C locks sell so quickly ?

A . Because their beautiful designs and outstanding m ovem ents have gained them first place In public favour.

TH E E L E C T R IC IA N

SCM I I 8 A

io O C TO BER 1947

1053

It is o n e o f t h e n e w r a n g e o f H E NL EY i n d o o r v e r t i c a l w a l l t y p e T e r m i n a l B o x e s , f o r P.I.L.C. a n d a r m o u r e d c a b l e s f o r w o r k ­ i n g p r e s s u r e s u p to 6 6 0 v ., i n t r o d u c e d to p e r m i t a m i n i m u m n u m b e r o f b o x e s t o b e s t o c k e d — y e t s a t i s f y t h e m o s t v a r i e d r e q u i r e m e n t s .

F o r e x a m p l e , o n e s i z e o f flat v e r t i c a l t y p e ( a s s h o w n a b o v e ) c a n b e u s e d w it h tw in , t h r e e o r f o u r - c o r e c a b l e , t h e n e c e s s a r y j o i n t i n g s l e e v e s , t a p e a n d c o m p o u n d b e i n g t a k e n f r o m b u l k s t o c k . A s k f o r C a t a l o g u e 3 5 .

H E N L J E Y

Terminal Box for s i n g l e - c o r e P . I . L . C . a n d arm oured cables.

C i r c u l a r t y p e b ox for 3-core

& 4-core P.I.L.C.

and arm oured cables.

Flat type box for twin, 3-core and 4-core P.I.L.C.

and arm oured cables.

TERMINAL BOXES

M I N I M U M S T O C K m e e t * M A X I M U M N E E D S W . T . H E N L E Y ’S T E L E G R A P H W O R K S CO. LTD.

5 1 - 5 3 , H A T T O N C A R D E N , L O N D O N , E C - 1

io O C T O B ER 1947 TH E E L E C T R IC IA N

A T IN G V A R N IS H E S

S T O V IN G V A R N IS H E S

N atural and S y n th e tic R e sin T yp e s

C O R E -P L A T E V A R N IS H E S

S tovin g and A ir-D ryin g

T H E R M O -S E T T IN G V A R N IS H E S A IR - D R Y IN G V A R N IS H E S

C L O T H V A R N IS H E S C O P P E R -W IR E E N A M E L S

A l l t h e a b o v e a r e s u p p l i e d i n B l a c k & C l e a r

©

A C ID A N D H E A T -R E S IS T IN G E N A M E L S

T h e a b o v e a r e a v a i l a b l e i n a l l c o l o u r s

Q

S L E E V IN G V A R N IS H E S

B l a c k , C l e a r & C o l o u r s

•

C A B L E L A C Q U E R S M I C A B O N D IN G V A R N IS H E S

C O M P O U N D S

V ario u s ty p e s

•

A l l t h e m a t e r i a l s l i s t e d c o n f o r m t o B .S .S . w h e r e v e r a p p l i c a b l e .

PINCHIN, JOHNSON

I n s u la tin g V a r n is h T e c h n ic a l D e p a r tm e n t,

15

C L IF F O R D S T ., L O N D O N , W . l . T E L E P H O N E : R EG EN T

7471

TH E E L E C T R IC IA N io O C TO BER 1947

S K

!*ÈÊf;WÈt- TÊt 4P

H a w k i n s

The FINISHING TOUCH

the E L E C T R I C A L I N D U S T R Y ★

A F irst Class Product deserves a F irst Class M ark

E

v e r

R

e a d y

“ T rapinex ” Paint Transfers provide the m odern m ethod of m arking first class products in brilliant effect, truly worthy of the greatest names in industry. T h at is why the manufacturers of electrical equipm ent featured here and many other leaders in all industries pin their faith to

“ T ra p in e x ” Paint Transfers, for capi­

talising their goodwill throughout the world.

“ T rapinex ” Paint Transfers are p rinted with special paint of colours many times

W A R N IN G . V O L T A G E J A C K S USE HIGH R E SIST A N C E V O L T M E T E R

^ E V E R Y I N D U S T R Y has a thousand uses for “ T rapinex” Paint Transfers (additional to the more obvious uses for publicity, display and packaging) in Work­

shop, Factory, Office, for Nameplates, Brand Marks, Monograms, Patent N um ­ bers, Instructions, Diagrams, Wiring Lay­

outs, Warnings ; Type, Catalogue or Serial Numbers.

brighter than printers’ ink. Any num ber of colours may be printed and applied to any smooth surface, in striking design or cut out effect without film or paper background to m ar the distinctive dis­

play—Brilliant, Durable, W eatherproof, and so easy to apply.

A D V I C E freely given, but when you write for prices please state: (1) Size, (2) Quantity, (3) Number o f Colours, (4) Purpose, (5) Word­

ing required, (6) A rough sketch would help.

WE HAVE N O STO C K LIN ES OR PRICE LIST S.

TRAPINEX ^PROCESSES,

T ra p in e x (R e g d .) P a in t T ra n sfers are f u l l y p a te n te d a n d m a n u fa c tu re d o n ly b y

T R A P I N E X L T D ., 1», C O M M E R C E H O U S E , H I G H R O A D , W O O D G R E E N , N. 22 >

'P h o n e : Bow es P a r k 68 11/3 'G r a m s : ‘ T ra p in e x , W o o d , L o n d o n C ables: T ra p in e x , L o n d o n

io O C T O B E R 1947 THE E L E C T R IC IA N

TELEPHONES Ltb. 2 2 , LIN C O LN ’S IN N F IELD S.

W .C .2

F o r a l l S O L D E R I N G w o r k — y o u n e e d F L U X I T E

— t h e p a s t e flux— w i t h w h i c h e v e n d i r t y m e t a l s a r e s o l d e r e d a n d “ t i n n e d . ” F o r t h e j o i n t i n g ' o f l e a d — w i t h o u t s o l d e r a n d t h e " r u n n i n g ” o f w h i t e m e t a l b e a r i n g s — w i t h o u t “ ti n n i n g ” t h e b e a r i n g . I t is s u i t a b l e f o r A L L M E T A L S — e x c e p t i n g A L U M I N I U M — a n d c a n b e u s e d w i t h s a f e t y o n E L E C T R I C A L a n d o t h e r s e n s i t i v e a p p a r a t u s . W i t h F L U X I T E j o i n t s c a n b e “ w i p e d ” s u c c e s s ­ fu ll y t h a t a r e im p o s s ib le b y a n y o th e r m e t h o d• U s e d f o r o v e r 40 y e a r s in G o v e r n m e n t w o r k s a n d b y l e a d i n g E n g i n e e r s a n d M a n u f a c t u r e r s . O F AL L I R O N M O N G E R S in t i n s — I0d., 1/6 a n d 3/«.

T he F L U X IT E G U N puts F L U X IT E w here you wa nt it by a simple pressure. Price 1/6 o r filled 2/6.

F L U X I T E

SIMPLIFIES

ALL

SOLDERING

W rite fo r Leaflets on Case-H ardening S te e l a n d Tempering Tools w ith F L U X I T E , also on “ W ip e d ” Joints- Price 1 d.each F L U X I T E L T D . (Dept. ERN), Bermgndsey St., S.E.I

R E S I S T A N C E

WIRE

8 0 / 2 0 o r 65/15 N I C K E L C H R O M E

• D R A W N T O RESIST­

A N C E , N O T T O SIZE

• BR IG H T A N N E A L E D — O X ID IS E D O R H A R D D R A W N STATE

• SIZES 20 T O 47 S.W.G.

O R T O B & S G A U G E S

Contractors 0 EV E N S P O O L IN G

'a d m i r a l t y » G O O D D E L I V E R I E S

W A R OFFICE G IV E N

AIR M IN IS T R Y

S T A IN L E S S S T E E L W I R E C o. Ltd.

The Barracks . Langsett Road Sheffield, 6 ---

Telephone: 44241-2 Telegrams: Fynew ire, Sheffield The “ F luxite

Q u in s” a t work

” R u n n i n g r e ­ p a i r s 1' c h u c k l e d E E " W e ’ re a l l c l e a r b e l o w n o w” c r i e d h e .

" T h a n k s to g o o d o l d F L U X I T E E v e r ) ) p i p e 's g o o d a n d t i g h t G o s h ! n o w th e f u n n e l s s n a p p e d ! S e e ’ ' .

TH E E L E C T R IC IA N io O C T O B E R 1947

1057

The article was a Copper Heat Exchanger

T h e J o b

w a s t o sw e a t o n t h e fin s u s in g a m in im u m o f s o ld e r an d m an h o u r s a n d w it h o u t e m p lo y in g s k ille d la b o u r.

T h e M e t h o d

w a s b y u s in g F r y o l u x S o ld e r Paint.

T h is w a s t r ic k le d o n to t h e t u b e s b e tw e e n th e fins. T h e w h o le u n it w a s th e n p lace d in an o v e n an d heated an d t h e jo b w a s d o n e . F o r q u a n t it y p r o d u c t io n a sp ecial c o n t a in e r w a s m ad e h a v in g th e re q u is it e n u m b e r o f sp ace d h o le s f r o m w h ic h F r y o l u x S o ld e r P a in t flo w e d o n t o th e t u b e s b e tw e e n th e fins.

FR Y O LU X Solder Paint

F O R T I N N I N G A N D S W E A T S O L D E R IN G

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io O C T O B E R 1947 THE E L E C T R IC IA N

o

1058

SILICONES

Silicone products manufactured by the Dow Corning Corpora­

tion are now available in this country. They include :

D.C. SILICONE FLUIDS D.C. SILICONE RESINS D.C. SILICONE GREASES D.C. SILASTIC RUBBER Stocks are sufficient to meet demands for sample and trial purposes. Further supplies are on the way. Enquiries for D.C. stopcock greases and Silicone fluids for high vacuum diffusion pumps should be addressed to Messrs. W. Edwards

& Co., Kangley Bridge Road, Lower Sydenham, S.E.26, who are the sole distributors o f these particular products.

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ALBRIGHT & W IL S O N Ltd

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io O C T O B E R 1947 ™ E E L E C T R IC IA N

15,000 NIFE ^BATTERIES

on duty 10 years

1060

for repairs!

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entirely free from corrosive fumes and im m une from damage even by

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T H E E L E C T R IC IA N 10 O C T O B E R 1947

T H E

ELECTRIC

E S T A B L I S H E D 1 8 6 1

Bouverie House - 154 Fleet Street - London E C 4 Telegrams : " b e n b r o t r i c f l e e t L o n d o n ” Telephone : c e n t r a l 3212(16 lines) Editor: S t a n l e y G. R a t t e e , A.M.I.E.E. Publisher and M anager: John V e s t e y

Number 3617 10 OC TO B ER 1947 Vol CXXXIX No. 15

CONTENTS

Views on Current Affairs ... 1061 Portrait—Dr. W. II. Eccles ... 1064 Codes of Wiring Practice ... 1065 Companies and Nationalisation ... 1066 Electricity, Coal and Economics ... 1067 Power Station Design— 1920/1946 ... 1068 Electrical Personalities ... 1069 The I.M .E .A ... 1070 Domestic Heating Methods ... 1071

•Correspondence ... 1073 Electricity in Persian Gulf ... 1074 Answers to Technical Questions ... 1075 Equipm ent and Appliances ... 1077 Booh R eview s ... 1079 Electrical Statistics ... 1080 Electricity Supply ... 1081 Hydro-Electricity in Sweden ... 1082 Industrial Information ... 1083 Electrical Inventions ... , ... 1085 Contracts Open ... 1086 Company N ew s: Metal Prices ... 1087 Commercial Information ... 1088

M I D L A N D S O F F I C B :

D aim ler House, Paradise Street, Birm ingham Telephone : M id la n d s 0784— 5

S C O T T I S H O F F I C E : 116, H o p e Street, Glasgow, C.2 Tele p h o n e : Central 3970

T h e offices o f T h e E l e c t r i c i a n are closed on S a tu r d a y s i n accordance u 'ith th e “ F iv e -d a y W eek " p la n ado p ted

b y B e n n B rothers, L td .

S I N G L E C O P Y (FRIDAY) - - - 6d.

(B Y PO ST) - - 8 d .

A N N U A L S U B S C R I P T I O N

H O M E A N D O V E R S E A S - - - 30s.

Steel and Exports T

H E sta tem en t m ade la s t w eek to the

Engineering A d visory Council on the su b ject of m aterials in relation to the ex p o rt drive, m ak es i t clear th a t n o t o n ly w ill th e electrical in d u stry be affected b y th e new h censing arrange­

m en ts, b u t so also w ill b e all tho§e other in d u stries looking for new electrical equ ip m en t to replace their war-worn plan t.

T h e contribution w hich th e engineer­

in g industries are exp ected to m ake to th e exp ort drive, is an increase from a b o u t £30 m illion a m on th in th e la st quarter o f 1946 to £42 m illion a m onth b y m id-1948, or 230 per cent, of the 1938 average— and it h a s to b e m ade w ith o u t a n y su b stan tial assistan ce in th e w a y of additional steel supplies.

T he circum stances in w hich th e engineer­

ing industry is required to im prove still further it s already exem plary exp ort record, are therefore such, th a t iron an d steel used for ex p o rt purposes w ill have to b e offset to a large e x te n t b y restric­

tion in th e m anufacture o f electrical m achines for h om e industry— and therein lies a danger th a t th e exp ort targets of other industries m a y be affected. I t is generally accep ted th a t th e m anufacturing o u tp u t of industry a t large, d ep en d in g upon th e particular trade, is governed b y th e a m ou n t of electrification applied t o it s processes.

D en y in g our m anufacturing resources new electrical p lan t is therefore, a risk w hich ca n n o t b e overlooked.

T h e e x te n t of the diversion of steel consum ption from hom e to exp ort will, o f course, vary w ith different ty p e s of

1062

m achines, an d in th e case of h e a v y elec­

trical plan t, hom e req uirem ents w ill con tin u e to be a first charge. O utside th is field, how ever, increased restriction in m achinery supplies for th e re-equip­

m en t of in d u stry w ill b e in evitab le, in th a t though supplies of electric steel are being d iverted from ordinary steel-sh eet cap acity, th e y w ill con tin u e for som e tim e to b e a lim itin g factor in th e pro­

d uction o f electric m otors, transform ers, and other auxiliaries for large an d small m achine tools. A s m uch e x istin g in d u s­

trial p la n t w ill th u s h a v e to rem ain in service longer th a n w ould in other tim es be th e case, it is possible th a t th e o u t­

p u t ra te o f th e machines', w hen co m ­ pared w ith p lan t of m odern design, is such a s to offer for a g iv en q u a n tity pro­

du ction , a longer su stain ed load u pon our generating c a p a city ; an d th is p ossib ility sh ou ld b e noted.

S anction or In cen tive ?

IN order to ensure th a t th e engineering industry is givin g th e ex p o rt perform ­ ance ex p ected of it, th e M inistry of Sup­

ply in ten d s to a p p ly an econom ic sanc­

tio n or in cen tiv e, as th e case m a y be, of relating allocation s of steel an d other m a teria ls to ex p o rt and other essen tial production, based on sta tu to r y returns t o be m ade b y th e in d u stry. T h ese co n ­ d itio n s w ill m ean th a t m anufacturers w ill in m a n y cases h a v e to reorganise th e w h ole of th eir sales policy, and p articu ­ larly w ill th is b e so am on g th e sm aller firms. A num ber of th ese la tte r are engaged in th e p roduction of electrical m achines for in d u stry, and official n o tice should be tak en of th e d esirability of encou rag­

in g th ese firms to a ssist their larger brothers in fostering ex p o rt trade, rather th a n entering in th e overseas trade m ar­

k e t on their ow n account. W h atever else h ap p en s under th e san ction -in cen tive licensing arrangem ents th e continued ex isten ce o f our sm all engineering m an u ­ facturing an d repairing firm s m u st b e assured, for their m anufacturing cap a­

city , w h en ta k en in th e aggregate, has a high p o te n tia l ou tp u t w h ich should be geared to th e efforts o f our larger or­

ganisations. To force th em o u t o f b u si­

n ess b y san ction s or e x p e c t th em to en ter th e ex p o rt field a t th is stage, w ould resu lt in a serious fam in e in m ach in ery on th e one h and and w o u ld d en y to bigger engineering firm s experienced in export

trade, th e in valu ab le support th ey give in sub -con tractin g and in other w ays.

S teel fo r T ran sform ers

T H E electrical in d u stry, fu lly alive to th e u rgency of th e problem of econom is­

in g in th e u se of sh eet steel and a t th e sam e tim e of doing all in its pow er to m eet th e industrial electricity load has, a s th e result of discussions b etw een th e C om m issioners and th e B .E.A .M .A ., reached th e conclusion th a t a consider­

ab le savin g could be m ad e if supply a u th o rities an d others, w hen purchasing transform ers specified th e h ighest p o s­

sib le flux densities. T his w ould n o t only reduce th e w eig h t of sh eet steel required w ith a consequential saving of coal—

ap p roxim ately one to n of coal is required for th e m anufacture of every to n of sh eet steel— b u t there w ould also b e a savin g in th e am o u n t of copper required for th e transform ers and steel for th e tanks. D eta ils of th e recom m endations w ill be found in th is issue and support o f th em is given b y th e Central Board.

The Coal P osition

A C C O R D IN G to figures furnished b y th e M inistry of Fuel, th e con su m p tion of coal b y electricity u n d ertak in gs during th e w eek ended Septem ber 27 w as 490 000 tons, and th e sto ck in h and am ou n ted to 4 024 600 tons, or on average a little less th a n six w inter w eek s’ su p p ly a t a consum ption of 670 000 to n s per w eek. I n th e im m edi­

a te pre-crisis w eek of la s t w in ter th e con su m p tion of coal for generation pur­

poses w a s 698 300 ton s, and in th e la s t w eek of J a n u ary 720 000 tons. Since th a t tim e som e 330 MW of ad d ition al p la n t h a s been *put in com m ission and th e to ta l num ber of u n its generated up to A u gu st la s t w a s 4.6 per cent, greater th a n in th e corresponding period of 1946.

Load Spread in g B egins

O P IN IO N S on th e first d ay’s load spread­

in g ranged from “ a reasonable response,” reported b y several under­

tak in gs in th e south, to w h a t Mr. Ge o r g e

Gi b s o n, chairm an of th e N orth -W est

R egion al B oard for Ind u stry, term ed

“ a disappointing result, show ing th a t th e area is n o t im plem enting th e pro­

m ises m ade to th e B oard.” T h e Central B oard are so far unable to express an opinion, and p o in t o u t th a t it w ill be

TH E E L E C T R IC IA N io O C T O B E R 1947

1063 several w eeks 'before th ey are ab le to

form a picture of th e position. W hile it w ould ibe u n ju st to b e too critical of the schem e a t th is early stage, it is signi­

ficant th a t the G overnm ent itself is app aren tly resigned to a reduction of n o t m ore th an 25 per cent., an d th e first reports give no indication th a t this view is over-pessim istic. The reasons for this m u st toe closely exam ined, 'because the sam e problem w ill arise n ex t winter, and it is on the experience of th e n ex t few m on th s th a t a schem e for 1948 should be p lan n ed —a schem e th a t w ill n o t only ensure th a t th e requisite load is shifted from th e d ay-tim e hours b u t th a t it is done in a w ay w hich causes the m ini­

m um interference w ith production, w hich th e w idespread ad op tion of “ pow erless days ” w ith o u t a com pensating increase in w orking hour§ w ill not.

M inister o f Fuel

T H E d eparture of Mr. Sh i n w e l l from th e M inistry of F u el a n d Power, a n ­ nounced on W ednesday, brings to a close an era w hich few in the supply in d u stry w ould regard as satisfactory.

Mr. Hu g h Ga i t s k e l l, w ho is prom oted from J o in t P arliam entary Secretary to th e p osition of M inister, show ed him self, during th e long deb ates on the E lec­

tricity B ill in Stan d in g C om m ittee early this year, to be w illing to listen to reason and to concede p oin ts to his criticS in a w ay th a t encourages th e hope th a t som e of th e m ore obvious d efects in th e control of th a t M inistry m ay be ab sen t in th e future. T he present G overnm ent is com m itted to planning to overcom e our econom ic difficulties.

On th e w isdom of th a t p olicy there are tw o sh arp ly opposed opinions. W h at is u n questioned is th a t if there is to be planning, it should b e done well, and th a t th e lam entable lack of co-ordination w hich h a s so far characterised m any of th e p lans p u t forw ard should be ended.

D irection o f Labour

I N carrying ou t th e redisposition of labour under th e C ontrol of E ngagem ent Order, w hich cam e in to force on M onday, th e preferential lists o f industries w hich were u sed during th e war have been revived. T he M inistry recognise th e im portance of n ot disturbing th e elec­

trical industry b y a n y transfer of workers, because, in th e first place of

th e urgent need to m aintain an adequate labour force for th e m anufacture, installation, repair a n d m aintenance of generating plan t required b y electricity su p p ly undertakings, and, in th e second, b ecause of th e contribution it is m aking in electrical m achinery, good s and ap p aratu s to th e ex p o rt drive. I t is claim ed b y th e M inistry th a t a t the m om en t there is no general shortage of m anpow er in th e industry, and, conse­

qu en tly, electrical engineering is not listed to receive first preference in the filling of vacancies. G enerating plan t m anufacture, how ever, is listed as

“ v ery im p ortan t w ork,” an d w hile the m aking of electrical goods and apparatus is n o t m entioned, Sir Ha r o l d Wi l e s,

d e p u ty secretary to the M inistry, assured a rep resen tative of Th e El e c t r i c i a n th a t such m anufacture w as considered to be essen tial and of particular im portance in relation to exports.

A ccident P reven tion

A V A L U A B L E contribution is m ade b y th e electrical in d u stry to th e success of th e Silver Jubilee Congress o f the R o y a l S ociety for th e P reven tion of A ccidents, w hich is being h eld a t B righ ton th is w eek. Special exh ib ition s are to be seen a t th e C orporation elec­

tricity show room s a n d in th e D om e, the E .D .A . d em onstrate m an y safety-first featu res for th e everyd ay u se of dom estic ap p lian ces; film s of E .D .A . v in ta g e are being show n in th e R oyal P avilion . On W ednesday afternoon a t a special elec­

tricity session, Mr. H . W . Sw a n n spoke on th e use and ab u se of electricity in th e home, and a discussion b ased on his rem arks w as opened b y D am e Ca r o l i n e

Ha s l e t t. T he subject w as trea ted b y

both speakers in a w ay w h ich m u st have left, e v en th e lea st electrically-m inded fully conscious of how electrical a cci­

d ents can be p revented, and of how, although th e electrical a ccid en t rate in th e hom e an d th e fire cau sation p ossi­

b ilities are com p aratively sm all, th e elec­

trical in d u stry a s a w hole is anxious to prevent their grow th. T here w as nothing in the su b ject m a tter of th e addresses w hich th e in d u stry should n ot already know , b u t from th e in terestin g s ta tis ­ tics given b y Mr. Sw a n n, w e n oted th a t ou t of th e to ta l fires a tten d ed b y the N .F .S . in 1946, 9.7 per cent, were know n to be electrical in origin.

io O C T O B ER 1947 TH E E L E C T R IC IA N

1064

Portrait—Dr. W. H. Eccles

I

T is an honour not given to m any to assist at th e birth of a new technology, h u t this, in fact, is w hat Dr. W. H . Eccles, F .R .S ., can ju stly claim to have done when, nearly 50 years ago, he joined the small group working under Marconi.

Since th at tim e, he has made m any significant contributions both to funda­

m ental theory and to circuit design; m any of the largest radio stations in the Commonwealth were designed by him, and all owe m uch to his work. In public life, he has advised Governments, played a large part on innumerable com m ittees, and done a great deal, by his careful nurturing of th e R adio Society of Great Britain, to demonstrate through the successful work of radio amateurs th e feasibility of round- the-world broadcasting b y short waves.

Suffering, in childhood, from a suc­

cession of minor ailm ents, he was educated largely a t home, deriving from his engi­

neer father an early knowledge of m echanical engineering. H is m ain interest in those days was in metallurgy, to study which he entered th e R oyal College of Science in 1894. Fortunately for th e world of radio, his affections were soon trans­

ferred to physics, in w hich he decided to specialise. A ttending lecture courses at the C ity and Guilds Central College, he concentrated for tw o years on electrical

engineering, a n d this led to his join­

ing Marconi in 1899.

In 1904, as he puts it, “ a mission­

ary urge ” took him into education, and for 20 years he taught, starting at the South W estern Polytechnic in Chel­

sea and ending as successor to Sil- vanus P. Thomson as Professor of Ap­

plied Physics and Electrical Engineer­

ing a t th e City and G u i l d s College, Finsbury.

These 20 aca­

demic years were among th e m ost fer­

tile of his career. A full list of his in­

ventions and dis­

coveries during the period would range from motor starters to calc u 1 a t i n g

machines. I t is interesting to note that an early patent of his for a “ trigger pair ” of triodes—in which one valve, on application of an impulse, draws a m aximum current while th e other be­

comes virtually non-conducting—remains a k ey portion of m any of th e electronic calculators made to-day. H e made an im portant series of discoveries in con­

nection w ith tuning-fork controlled oscillators, w as a pioneer in crystal control, and am ongst m any theoretical tasks, he gave an early explanation of th e trans­

mission o f w aves within the ionised reflect­

ing layers.

“ Of public works,” he tells a ques­

tioner, “ I have done a fair share.” To demonstrate the understatement of this remark w ould demand more space than is here available. I t m ust simply be said th a t, for at least 30 years, there were few im portant m ovem ents or com m ittees in the British radio world w ith w hich he was not associated, usually in an important capacity. During the 1914 war, he did m uch for the fighting Services, helping to develop transmitters for the Army and submarine locators for the N avy. H e was instrumental in establishing the D epart­

m ent of Scientific and Industrial Research.

Soon after that war, Eccles became vice- chairman o f the Imperial Wireless Com­

mission, and this contact w ith world wireless led, in turn, to the chair­

manship of the design committee responsible for the G .P.O . station at R u sb v. In 1926. he became consulting engineer for the Eastern Telegraph Co., and later for Cable and Wireless, and other com­

panies.

Dr. Eccles has been President of the Institution of Electrical Engineers, the Physical Society, the Association of Scientific Workers and the Radio So­

ciety of Great Britain.

H e lives now in Roehampton. He is a keen walker and swimmer from his youth.

TH E E L E C T R IC IA N io O C T O B E R 1947

1065

CODES OF WIRING PRACTICE

by “ S U P E R V IS O R ”

T

i HE British Standard Codes of Practice Nos. OB(iB) 025/1946, Electrical Installations ('General), and OP(iB) 627/1946, Choice, Installation and Main­

tenance of Electric Wiring Systems (for Power, Lighting or H eating Circuits) in

¡Buildings, are apparently now published and available to the ' public. Judging from the fact th at the copies sent to the writer still bear at th e top the words

“ Draft for C om m ent,” and that the actual numeral spaces aTe left blank, three things m ay be deduced. One, the copies were sent in error; two, the rush of applications has been so great th at recourse has had to be made to draft copies ; and three, it does not m atter anyw ay, as the published Codes are identical w ith the draft.

LITTLE TRADE INTEREST I t will be remembered that prior to February 24, 1947, th e drafts were cir­

culated for comment b y interested bodies and others, but the writer can recall no case in w hich any public discussion was initiated on the drafts, nor has any com­

m ent, beyond his own puny efforts in these columns been made in the technical Press. This again argues tw o things—

the Codes are perfect, and quite reason­

ably represent the accumulated wisdom' of the ages in the field of electrical installa­

tion technique, alternatively, the technical bodies of the industry and individual members of it cannot foe bothered to comment.

In the course of his daily occupation, the writer has to travel the country and talk w ith supply engineers, consumers’

engineers, electrical contractors, 'archi­

tects and representatives of housing authorities. lAs a result of these con­

versations the writer is unfortunately compelled to accept the second of these alternatives, as practically nobody has even heard about tbe Codes, and could n ot care less about them and their con­

tents. Only one consumers’ engineer had copies of the Codes, and his comment was to th e effect that they appeared to foe identical w ith the I.E .E . Wiring Regula­

tions, and were therefore unnecessary.

Comment upon the apathy shown in connection w ith local and Parliamentary elections foy the man in the street, must surely foe surpassed b y the lack of interest exhibited foy the average member of the installation industry in anything affecting the technical progress of his craft, and which m ay possibly take him away from

the well-worn paths of age-old practice.

N ot thus w as the electrical industry created and developed, and the present- day attitude has the effect of damping down the few enthusiasts that still remain.

This apathy on the part of installation engineers means that others, more pro­

gressively minded, can impose all kinds of things upon them . Supply engineers rule the roost in m any areas as to what kind of installation shall foe connected to their mains, and retain a power of veto that outshines that of our Russian friends as day does night. Manufacturers impose sockets and plugs that nobody seems to want but must accept, and now we have Codes of Practice that installation men will undoubtedly grumble at when they come to full comprehension, but which they could not foe bothered to discuss when time offered an opportunity.

Amongst the tw enty-five members of the Code Committee the writer can detect the names of some four, or a t the most, five, eminent men truly representative of the installation side of the industry.

Able m en a s they are, it is unreasonable to expect that with all the other interests represented they could secure a definite installation outlook on all the matters discussed in the preparation of the Codes, in fact, they must be congratulated on the fact that the Codes do, even in their in­

adequate way, m eet modern needs a t all.

The blame m ust lie a t the door of the trade itself, as the opportunity was there for discussion, and, possibly, for some amendment where necessary.

EARTHING PROBLEMS

The writer will repeat his two mam criticisms of the Codes, and the first of these has to do with the section on earth­

ing, in which the very existence of the voltage-operated earth-leakage circuit- breaker is ignored and, foy implication, damned. Prior to the war, most pro­

gressive installation engineers had come to realise th at danger from shock in installa­

tions w as due to leakage potential, and that leakage current only came into the picture in so far as, b y its passage over resistances in earth circuits, it °;ave rise to leakage potentials. I t is, therefore, sur­

prising to note that in para. 513, Preven­

tion of Danger Arising from Current Leak­

age, three alternatives are given to ensure safety, and are : (a) Over-current operated devices (fuses, and w h at-n ot); (b) leakage-

io O C T O B E R 1947 TH E E L E C T R IC IA N