Document nNabd9pkbrwMjjYwnEJmMQ3kX

o 499 i i \ * 1 o LEAD INDUSTRIES ASSOCIATION 0 CAST 42m* STREET NEW YORK IT# N. V. COPIES SOT /ISO TO KRUiEmmO AXD FURCSASIBG FERSCKHEX OF HEWER C0HPA5TES July 2i, 1959 SUBJECT: "LEAD HEWS* To the Meahers of the Lead Industrie* Association Through reciprocal irrangeaents vith the Lead Development Association, which la our counterpart In a\g3e.ed, ve ere pleated to tend you the latest issue of their serdanr.ual publication "Lead Kcva". They are, la turn, distributing a quantity of our quarterly publication "Lead" la England. We hope you will find this publication of Interest tad value. We will plan to send It to ycu in the future as Issued. Very truly yours. Enc. Secretary v r u '" lW U1 f IB^ I ;W W W o f *' m ' I "'UPH.I my jut MWMSIIWUWP w w p miu mjjjj. i l 1^2Z5 V tfUkii >inw LU22502 ms*m Lead News A Periodical I'ublieathn of the Ixad Development Attoeiaikm NUMBER 7. VOLUME I, MAY IW? c o nt ent s UwU fur > Rata Maitr Hfc purr 4, M mi 9 Itat^r (' wlwM /Mfr 4 \*w4 ta McM ImAatfM p*t< 5 In* SUrUtac ta a Nvcfcar *tkr p it ft A Rafter? Railcar pm* T Ctactaw ftaml pm* H OU In* 1m No* kumtt Akita pm* 13 In4 Httan ptprt 14 nd 1 ImM Sata pm* 13 |<k ld hmmttmm pm* 13 : Dir r i a l .... TPM!' Lead Dcvehpmcnt Association ha* now published and some account is given # the General Manager** visit m Revie* tv# Services fvr the year 195*. It describe* last April to the l nited Slates and Canada and of his tour, K>w important steps were taken during the perid to con accompanied by the Technical Manager, to effect contact* solidate the fundamental dcveh>pmcni in its rtp*Ju\ with friends and counterpart <vpam/alions in Holland. *f*rrunJi which cxvurred during the pre*iHis IK ftMmths Germany. Belgium and t ranee in the autumn. In an endeavour to stimulate a better apprcviatin <# it* The Review in*.Judes a reference to the l'Dried Natiom vcrviccv a record lus been made of the various ways and ('onfcrcnces on lead and Zinc held in London and Geneva means which have been employed In further the objective* in September and November respectively, at which the # the Aweittion. Assiviatnm was represcnicd. anJ a comment cm the figure* The report commence* with a brief account # L.n.A.** ' of cmsumpti<vn for lead in the IVK. b* 195*. background and development. and gne* on to recall the I irutly, the work of the Lead Shed and Pipe Section c# 'tapes whereby its interest* and influence have grown The the AsMviatHm i\ described in some detail. The document technical activities <# ihe Awtcislion during 195* arc is supplemented by illustrations anJ five apfxndiccs giving uAcrrd by paragraph* on held visits, research, library, details of membership, committee*, staff. publKalxen. "Technical Abstracts**, kvturev, advertising a.'d editorial, film* and consumption figure* be lead for the period and mention the hnc future policy is likely to lave. 1949-195*. In the matter %d public rclatiotts the Revie* no *n infor mation *n current I DA publications and a ik * him. If f grtbollt Hof fpf Hit Ktvltw * htta "l.ead Ihe I ndunng Metal", which will be avail We by poifr# with fkh trfif/aa */ Lt# Metre, Rtf M HH h mid I95. atf fit ctt # yta wtaf# ht laftrtsftd H t99* H Considerable headway was made by LI) A. djring the f laafffc, pltttt 4* atf Lti/frft ft Iffy y##r period under review in the sphere of internatior J relation*. reftttf. 3 L1A22503 RAIN WATER HEADS Cast lead 'min* iter pipe-heads" are another of the many examples *4 the remarkable Uwg life *rf lead for the essential purpsc of exclusion and dispersal of rainwater frKti buildings. From the fourteenth century. lead ha* been used by the plumber a* an expression of fancy, and in later years, to the design of rwir most famous architects, to make thc*c particularly F-nglish feature*. The tradition has been well maintained and it b often possible to date a building from the design on the head* or. in many examples, by the actual date included in the ornament. There is at Winds** Castle a cast lead rainwater head dated I5W. Lead rainwater heads and pipes, properly made and fixed with equally permanent materials, will certainly out' bs! the Mirnmnding fabric of a building. They do is* require any maintenance or protection. Where square wtion pipet arc used, whether on Ihc face of a building or built into a chase, they are unaffected by the inroads of rust or corrosion on the inaccessible fare* The rainwater beads illustrated on the front coser are two examples of current sirl; on the left ft* the HawkerSiddeley Building at Kingston-on-Thames and on the right f<* Marwhcster I'mscrsity N*h designed by Sir I. H Worthington Tbo* illustrated in the centre pages are;-- From left to right lop: Bristol Council Office* <F. Vincent Harris, o.m^ t.I.I.RA). Citify House. London (H.and M Lid Setter. i->.K.a^) lonJon l niversity (Adams. Holden and Pearson, t tji.i.a v). Guildford Cathedral <Sir F. Maufc. t.t.t.*jx.L Middlc Temple. London (Sir J. H. Worthington. o aJ- *JX.. From left to right bottom; Sissinghurst Castle. Kent (Sir 11. Maufc, k .v . tjt t.n O. Royalty Court. London (Thox. and Peter Braddoci. t AI.I RC) House* of Parliament LonJon (Sir Giles Gilbert-Scull. <*m. m., tat aO. I'nisersily College. Lond<*i (Sir A F. Richardson. .4,, tJt.i.n.4.). Kings Set** 4. Canterbury (Braddell and Lawrence. An.t.n.A.l All these examples were made by StK*f and Saunders Lid under the personal direction of Mr. S D A Saunders. o ItOTOPr COM 7 A f\'RS A recent adjourn to the now k*ng list 4 Wad tilled containers u h .-J in industrial radiography has cotac to notice 11k main bulk of the umt comprises a caM-Wad shield In a<M*>n to being used for radiography m utu. the is*t*pe can tv used in unijunction with a handling rxl (.ir "*jvn source** techniques. 1 wo si/cs o( container are available for use with Iridium 1*0 or rliulfun' 17*> I he smaller may be accompanied by a lead lined box (or extra ptoteili<>n during transport, and the larger is completely "self-protecting", basing sufficient thickness of Wad "built in'* all round Ihestf itmtamers consist of two advent parts, which male ahmg u spherical surface When ckwed. the radio active capsuW is kvalco centrally at the join To open, the top ps>ts a Knit an axis Waled at the centre *4 curva ture <4 the mating surface so that rays can he directed hiKi/iHilally 11k illustration pmtray* the container in the o j v ii pwition. 4 e vur i -PIJIiiynX<U".mwuw wmuo'--'.y' V-. mummiiuu i .ij i.i imiJi!ljr/jJlJ*Bt --------- T**'*1 ' LI*22504 LEAD IN MEDICAL IRRADIATION e 71k use of lead at (hr shielding medium in Medical Irradiation l'nils it fvm well established. At net instru ments appear in ihit held, Ihe tcndcnc) it increasing to accept witNntt o*mmcnt that their chickling will consist id lead. and (he inherent properties d the metal are. at a result, inclined to he overlooked. In (he treatment of tumours do*< to (he akin, such at lKe in head and neck, (he vital problem it hi deliver an adequate d<we of radiation to the tumour, without exposing the neighbouring health) tissue to excessive irradiation. The general practice emptied to achieve this has heat to u*e a narrow -focussed** beam of (he rsdialkm. This nvtNxJ nornullv employs a spherical lead shielded naLoner (r general potcclitm and a lead shielded treatment fsv/le. I arlv units were the wctl-knitw* radium funs which contained up lo lOgmv of radium. With (heir massive lead shtckls. thev were later owiserled for iik with up to lit) curies tf Cobalt ) New units have since been dev^ned anJ h k which has Seen developed special!) to prrnide a range d sh>rt and nKdium distance techniques is %4 special interest. Ihe instmnienl. known as a twir.-siHirct Cobalt Mt tele* o theraps unit, has a total w*urce strength of |.t *1 juries id Cobalt Nl It is illustrated tright) and a scctowul diagram fhclowl sh*ws the nussise lead hlled sled shtclJmp cootuner The shield is capable of containing the source so eflwicntU that the raJuthm at the surface of the instrument ' onls aKnit t* millirocnlpctts hr In approximate terms this implies that an operator w h iIJ have to stand in utnlasl with ihe unit f* a six-dat week, *4eight hours per das. mi f i> m-stirt ( ><Si/l nwt indct to recrise the acerpted maximum permissible dose of radiation. Perhaps an even more impressive indication of the prKcctHin given hs this lead shield is the fact that it would Nr nc*.essar> to stand at a distance of over sards from the unshielded source to he as safe as an operator in actual physical contact with the unit. Jl s1lvUsJ lim l |U(Vt ciUilW Ni'* XIi ^mu I *nW (V*k J ftt+uulj t *<. by () S fccjiij and < |w< H-itki) the f*K PtJn' ( "(friente WrU mi Irenes a m VfWsi tvs | L t , l i a 2Z505 ,T j^^..--i^T.i-:------------ .^-r.^.Ai, -^.. - - ------- rr^L.:,---- --------------------- ...... ------ .LAD SUiLLDING fN A r' > .- / > R ` i. li R o Whilst Nuclear I'nerpy us a source of propulsion may he considered at present to he somewhat uneconomic. (he special situation which arises in the case of a whalinf factory ship makes this ty pe of power unit a very practical proposition. In this kind of vessel a reactor can be used not only to provide the motive power fix the ship itself. Sot also steam fix the various processes carried out on core consists 14 lug plaic-typc fuel elements and is arranged as indicated in Tig. 2. The '-'vcrall diameter of the core k 130 cm. and its height I mo cm. This is immediately cur* FK, I Vl !* * lri #**f rounrbd In i cm. kater reflector khich in turn is blanketed h\ a I cm. laser of indium prmiding the isotopes employed fr irraduiMHi of the pnducts f the factory. Circulating around it o the kuter khkh is u<d both for nvtderatkwi and cooling. Phree 5 im steel pblcs kith 2 cm. coolant passages NMkcen prosnle the necessary thermal vhiekJ. and a further * cm. space o u ImJc the shield is similar!) katcr<oi4cd. The core, kith its indium blanket, cooling katcr and oed plate tbcrnul >hcld. is contained kithin a 12 cm thick pressure scv*l* the khole of the imulbtion being sur rounded kith X> cm. *( lead, khkh is reduced to 10 cm. on t<p if the reactor. The bottom is unshielded. bast ncutr.xt shielding is of course. supplied by the kalcr in the reactor and the lead pennies gamma shield ing The installation kill cmNvJ> approximately 1)5 tom of lead, arxj a further quantity kill be uxd as a container in khich damaged fuel elements can be off-loaded ft* storage khen the ship returns to port. Kmo J as kcll as for ivitopcs for irradialkm of the product* <f the factory. The type <f reactor at present proposed fotUmv a s*Mdy by an international team of engineers as part of the Nuck tr I ngineering Programme at the Cnivcnaiy f California. A cross section is depicted diagrammalically in Fig. i. The 4 *i r * J- -g - , mjm tmm !' maifuwPflu1 m "Li 'WjyBM-- ,, ' U1A22506 --,, -.^ ----- - ...a~-^:-I- ---iriY M3 > / a ' A I LG A R The first iin*ar buttery railcar to be seta in Great Britain ha* taett on trial the Abcrdeen-Ballalcr line of the Scottish Region British Railways end appears to have proved successful. The photographs shorn the full train with the batteries in position. 1 he butteries. each weighing X tons. are carried in two half sections under the vehicles and comprise 2lh lead*a*id cells with a soilage er 440 and capacity of I .(.`TO ampere hours. They are housed in cradles so arranged that they can N: partially withdrawn for maintenance and insjvxlion. With lead-acid batteries. the operating sxifuge rarely varies by more than * $' and 10 . and this facilitates the design of the traction equipment. In addition, there are none of the inten uptionv in the motor circuit due to jump ing of a collector shoe or pantograph. Battery-charging equipment comprising circuit-hreaLerc. transformers and rectifiers are provided at Aberdeen Joint and Ballaler Stations. The batteries are charged at a high rale whilst the train is standing at the platforms during lie-over perksJv By sfxvial arrangement d the electrical circuitv the charging cuNcs cam** be connected or di'connected from the train while they are alive, nor can the train he moved while these are connected. Air ts circulated through the bactcry com partments by electrically operated hkmers to psevetrt the butteries overheating during charging. __ 0*WV Awwr t**f Itr Mswi fsutintty *MWrsiv tmd i*i/*rrtum fm Mill % Ml iiii i i m '1 UHWIIH *lBM iWF.ai^ji ! nii|f [ini ' --~ wm KJ l I,,22507 % % =5P ipi*!l" HI iJWJgJBgPW z 250<' *S r r 'ifcr aiAi *r utHMifeiiia MiaUbiMtUiMajia* CALCIUM PLUMB ATE u .4 P/u V'.'A T Of- GROWING / 'SIPGGTA hC There arc man) factors lo observe when using paint to protect a Med surface from corrnMoa. and neglect id any of the*< will usually accelerate failure. The advent of a new and effective pigment in this held h not, therefore, the solution of all difficulties, hut it d<ves place a piwcrful weapon in the hands id those concerned with these prob lems. Calcium plumhaie has heea known fie over sixty years, hut its use as a pigment in priming paints was me suggested until the middle of the last war during an investigation into measures for economiunf in the use of lead. There is a strong suggestion id a marked similarity between calcium ptunihab*. which is really calcium ocihnplumhale, 2CaQ PtO. anil red lead which K lead orthsplumhate IffO PW) Woen made into a paint with bnecd tal. it was found cspeimentally to have ruv*-inhibitory pi*pertiea of the same <a der as thoe of red lead, and it a clear that it had conside.able promise. Manufacturing methsh were desned to give a outsisacni pnslisl and large-scale held triah were put in hand. About |U50, the material Nrvame available commercially and its u>e in priming paints hv iron and steel has grown steadily since. It is now widely accepted that the rusting id inn or sted is an electrical phenomenon. Ihe surface id a com mercial steel article is not ah-*4uteh uniform, but contains '-h o c areas which arc nswe active. electrically. than the bu!k id the metal, while o*her areas arc less active. If (he surface is wetted, small electrical currents will fV*w ipn* taneously from some pints id the metal (called aooiol into the liquid and then back once more into the metal at other regions (known as cathidcsl. At the anodes, atoms id the metal are taken into sotutiiwi by the current and a secondary chemical reaction subsequently converts these metallic ions into the famihar rust. Rusting id a Meet article can therefore be presented if this ctcctncal circuit can be destroyed. Painting irffcrs several ways id doing this. One methift! rs to try to displace the liquid in contact with the surface by tnc substitution id a paint Mm having a high electrical resistance. This is not particularly efficient, since all paint films are permeable by moisture to some client, and the electrical current can continue to how. though pwsiNy at a lower value A better system is one in which the paint suppresses the anodes. In these cases the active pigment alters the comti- lution id the amslc areas and the IVw of current is stifled at its source. One drawback to this process is that if a breakdown iveurt and one amvie becomes unprotected, then all the neighbouring call*vies will concentrate their influence on this one spit and com***) at that piint will be unusually rapid. A requirement, therefore, id a paint which protect* by this mcthixl is that it shouKJ pisses* good pmers id scaling off any breakdown which may acci- f(M 0t Ims Mn k iiM nuiti d/twt f**m*r4 *nk dentally ixvur in practice. There are a few paints in Uws class, ch*<f <d which arc pnmers based on fed lead, and the outstanding reputation which the latter have earned in centuries id io would not have been acquired had they been deficient in this imptrtan; property. Vet another nxthxJ protection would be to destiny i* inhibit the eathwkv This wiwild have the effect id It) HjHWl -i* J WUWJ JMW.WlwmamWWIH* WW |_IA22510 *3ms* mirndSi^mm i rt-rnirftirmiMifiii^"'-- "^'t dttfaaQm Mopping the flow <d ckvtrk.it) and in addition would provide a safeguird against breakdown Should break* . down ivcur. then the espoMvJ cathode would certainly attract current friwn all the ncarh) angles hut the destructive effect id this current (ctrrosion at amrie areas) would he spread over a forge number id points and the damage at any one spot would he small. I'nfoetunaldy. the properties required by a pigment to meet these require* mcnls often render it unsuitable in other directions as a constituent of a paint. ar>J there arc few material* which prose satisfactory in all respects when put to the test. Calcium plumbate appears to be one of the few Although the mechanism of its protectise pimcr is my fully elucidated, there is a griming Height id evidence that in a priming paint it priMecis the Mccl by supprev*'*! id both the aruxltc and catfoxlic areas id the structure. Apart from these ohsious advantages, there is another ti'O'equcrKe which is n<t ms apparent at first sight. It ctu)ecms (he hchasuwir id limbed **l paints mith sea *aU*r Paints containing this scry useful vehicle will Mister and vdten when they have been applied to a steel structure and Liter exp*<d to saline spray It is uwmvMiK hekl that the activity at the catlvxJic areas is reqvmsiNc fi*r this. V*hen cakium plumbate is invitrporatcd in the paint, this effect is not observed (believed to be due to the suppression of cathodic activity) and as a consequence the paint has a much longer life. The paints are no* finding extensive me in the priming id ships' superstructure*. Calcium plumbate has a number of other characteristic* of advantage to a paint pigment. Its colour is light buff, whkh pernitis a Hide range id colours to the finished paint: it has a ciHnparativdy low specific gravity, thereby riving a paint with a K>h Height per gallon: it mites well with oil to give a paint id good texture, although a small amount of a dispersing agent is usually added to preserve this properly on storage: iu rust*inhibitory properties are so pmoounccd that the incorporation of a fair amsHint of extender in the paint is possible; paints made with this pigment cover well and leave few brush marks--the* idten being a source <d weakness in a priming paint; and. finally, a film of a cakium plumbate print on steel will continue * harden and toughen long after coats of other paints have beat .ippikd on u>p. although no ca^ Has been reported where the hardening has pfivccdcd to the point of cracking. Hie alkaline nature id the pigment calk for some com ment It is pftdsuhly this feature which is mainly responsible for its fcnehciaf suppression id catKriic activity on steel, and it K also useful as a neutralising agent for t(g harmful & lIHmUIIIU -IT'*. :V.K. WBS HFiiyeb^wvlj- iv*h-fhhLUll([ [iff Q[ H ki turn .vr..'. Vii* m k, ^nwrW b rwk (mm gtttmfmtr II ^01 sjuiijCPii _ KCX* NJ J1 .} * i '.in * rv ' V*vC1i tm Jg w h o b b imu ^i w i).Cii*P^ ...... n up wiwiiwj^g^jBWPwi l U225U --- - rinn-n-riurti- - --p* acidic brcakd<*wi products *f the organic constituents of the pa<nt. Despite this alkalinity, it is possible to use cakiun: plumhate with a fair range of media, and further, it does (v h Mrem to affect alkali'sensitiv.* pigmenu st*h as Prussian Blue. Probably one of the features of cakium pJumhjlc paints which has the greatest appeal to the practical nun in their ability to adhere satisfactorily to a variety of `difficult' surfaces. Thu*, they can he applied directly to no* galvan ised iron without the prior use of a mordant or recourse to weathering. Galvanised iron has always presented one of the biggest challenges to paint leihnologisis and many combinations if treatments, media and figments have been tried in the past with indifferent success. The advent of calcium plunihale has solved these difficulties without the use of special techniques or unusual formuUtkxbL As far as U known this remarkable adhesion to galvanised iron is unique among painlv Practical tests have shown that (hc< primers alvi adhere well to hardwoixJv such as oak. and further that light alloys (e g. aluminium alloys) can be primed with every confidence. This article, ahkh is written to introduce (his versatile pigment to a wider public, dies not purport to five working details of interest to a paint manufacturer or chemist The makers arc Associated Lead Manufacturers Ltd.. Clements HtHise. 14-in Gresham Street London. E.C.I who will gbdly forward particulars on request --Or*w ,i, |iii >^ I I l u n m i i It4 J Ollif f*tmrd Ha fdl i*.m mmfrr*te4 Red 4*iidc peimtd i<4 r*J****.'rd ire* milled nilk mkitr fettm ft*. U - V jyfSPJ1* an am w+ m j i mu l u j w i LIA22512 n ti uifirn-iraMhii &OLO LEAD FOR NEW ATOMIC SHIELDS 7 V /*. Several references have recently been nude to the necessity for using old lead to xhieW certain instruments used in (he detection and measurement of various ionising radiations such as X and gamma rays, giving rise in some quarters to the false impression that only old lead is effective in shielding applications generally. This. <4 course, is not correct, and new or freshly mined lead is widely used foe shielding purp*<s. SSng entirely satisfactory in all but a very small minority of can's. The exceptions con cern a few specialized instruments designed to detect radiali<vn of km- intensity levels. Pic circumstances in which lead ore is found in the natural state are responsible for this situation. Most ore bodies are avwtited with rock formatiom. such as granite, which have a small degree of natural radioactivity. Hence, new ly mined load is slightly contaminated and emits a very ifeeble radiation, which is not affected by the subsequent < melting and refining privcvcv The resultant primary lead >n therefore scry slightly radkuctive and the activity is such that within 50 years of its pnduction it may he considered to have *"died". Deschvpmenis in atomic energy and tlw u*e of radio isotopes hive necessitated the detection and measurement .*( scry weak radiations. One of the instruments used for this purpse i* illustrated It is a high efficiency scintillation c**unief in which a liquid plvwphor la substance which . delects radiations! c-mtamcd in a glass reevptacic is uwrd to cHini the radiations fri*m an immersed weak rnlio- adise source. The whole unit K surrounded by a massive lead shield *f minimum thickness IJ in., to prevent c sternaI rjdiatMKts necessary to specify that the shields for this typ: of a|f*ra- from interfering with the esperiment preceding inside. tus should he nude from old lead. Such instruments are When experiments arc being performed involving comparatively uncommon, and the market for old lead extremely k*w intensity levels, it is found that new lead which they offer is quite small. The amount of k*d avail used to shield equipment frm external influences May give able from nornul demolition work is quite adequate to rise to suffwient extra radiation frinn the metal itself to supply the quantity required, and old lead has. therefore, interfere with the (Measurements. As a cs*nsequence it is no enhanced commercial value in this or any other field. 1 15 PW '1'iiiiqwg i wwrv>-z in I 'win- i!JtyiWB^Mjj.4T^jui|!iaiBtB^WWpwwWiP|WWp^^lpWWa^pCBW^^^[ L r A22 513 n n liifriNrHi'nnirftMMrfftMrt LE M ~v W A Sri EHS /Niter ltd ANfff virm-t of ihr \Utiy tVr ht ft**f miffrrrmi dirt The rlJu'tfjtHWi the inside front cover of this edition shoe's a selection of some of the nuns tspss of lead washers which are currently available. It has been the practice in small laboratories and work shops to satisfy special requirements b> cutting from pieces of sheet lead. Nowadav*. many different types are in regular pcrxluctioo and are used in a numher of industries. The two phol(*graphs illustrate the use of one particulai patented tspc washer. It is a sleeve washer, used for corrugated nwfing applications and is an improvement on plain cupped examples which have been used because of their ready adapuNlit) to irregular shape*. If extreme pressure is exercised on the nut and boh u^ed with the washer, the plain cupped type can lose ib conical shape, reducing the efficiency <4 bedding down. In roofing applications, this can cause looseness to develop, with resultant instability and tendency to leak. The introduction of a sleeve washer was desigwd to overcome these drawbacks. Here, the >ole is not cut but b proved in such a manner that the material from the centre of the washer is forced inwards, producing a solid neck or collar. When pressure is applied on the^ nut and bolt assembly, the tubular centre meets the roofing sheet at the same lime as the outside edge ts adapting itself to (he contour* of the corrugation. At this point only the most i vicious application of pressure will cause further spread or collapse, and the washer retains its original conical shape, thus giving a double-seated, permanent solid and water* proof joint This /mturr i/kmi thf m> W drtvt mu\kcn ft* filing 0*rr1 to n>of fmriiits 0Tlwr; M tfftnrd d***H Srrtiom tktomgk crMrr of turi. hall mud matkrr 14 9 T"TlA225l* s r L tl.H o An increasing interest in the merits 4 leaded steels K becoming apparent. Information from the ITS.A. suggests that nearly 50 <4 the har steel used in that country rum contains lead, and extra plant is being brought into commis sion to cope with a griming demand. From Australia, too. there is news i4 rising consumption. and it is understood that steps are no* being taken to establish production ta (hat continent Lead is added to steel to improve its machinahility. The lead. which k present as minute spheres homogeneously distributed throughout the steel. acU as an internal lubri cant by smearing over the buried tips of cutting took. The amount of metal required is only about 0..)/ (i*. 7 Iba. per ton of steel). It K ftuind in practice that this addition makes no difference to the physical or metallurgical properties of the parent steel and that the ease of machin ing arises solely from a lubricating action and not because the steel is in any way made softer. It is evident, however, that in a number of countries, including the U K. there b still a lack of appreciation of the commercial merits of this material and it is considered (hat the time k opportune for L-D.A. to assist in the dissemination <4 information and to stimulate interest j .; o - so AM A LG s a \nulcams. such as arc used f*w mans industrial and An interesting application of a lead amalgam k the denial powcsscN. are pfiduccd from mercury and a vaiieiy 4 alloying elements In most of these, mercury is one of he minor ingredients. and in a revent example the principal ..Histitucr.ts are 32 lead. 27.4 tin. 16.1 chromium. >5.4 mercury, and'Ll cohak. The new amalg-tms arc described as **silvcr*likc~ alloyv jnd arc apparently equivalent to diver for many industrial subject of a recent German patent. This dewnbes battery grids made of 6 mercury and <*4 lead, and claim* that they have 53 greater durability than tbo^ made from the conventional leadsmtimony alknx. For general purpo^s it is sufficient to make only the piwitiuc grid of this alloy, hut in cases where km *clf-diw.harge k important, it k an ,`fvvcssev 1 hey arc used both in dentistry and in the pro advantage to construct the negative grid aho from this duction of silverware and art articles. matcriaL ' : L ZGT HI C*T Y v ft p p l y We must defer giving further details <4 the cables which will 'ink the British and French electricity supply systems as vjicuted in twr last issue Fult-watc triak t<xk place last Autumn, but sufficient data hi form the basis of a report it at >ct unavailable. 15 II ILl'pgOp w.w i lgr r^n- I.i^a||,i|* .a; Jtmjny U> w-wis ww ti* r*w <*3)9 -a* Ta 3 *515 '- - : > : r 4 ; : r| r ur >> : ; limi tofrt4~T>.B Am rECH NlCAL PUBLICATIONS \ toksfeJ U4 <4 Mtr* >4 >r..Mb f-M.4-4 UiMM i^tiauMr |M* 0k aOt<J--J IfUh %* tMftH W) at fn< 4Im N >--! W Mr*-- MteWWIl \ f 4to itJm ad A 4 j inn u<a wf*. mi n j. TW Sa*4 <I.I.0> at Caw to I J h 4.na-^_ 4 t In- We.W. 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I hi* h*4, *u\ u>mn>t>Mi>f)cd b\ the B*iard *4 IhrcvMo 4 the l.ondon Metal I uhancc It in a hiMocv f the lv.hjnpe and provide* a o*mpfchcnvi\c iicumnt 4 itv ttfktn> urxi <*yjnt\jti<*o. and iIc n aCj Iv * h*m the L*nd*n I uhjngc to fx\.<*mc Ihc Htf|*|\ k\Jnp market f<r tin. copper. Ic.id and /u k I Ik* Mrrviec* the market has provided l*r tlie metal induvtriCN arc explained in detail. there arc fHir pap> tkwc*lHJr maps vKmmg ifcirld pndiKiHyi and i.Hi\un<ptHtn <4 the have metah. l*iv-kt4Hir tharix. 12 illuNtrali*m, f**ur apfvm Jk c n a.*xl an indc. f*uNt\hrU by (Uf /.n*nunf\/ Intt lUririu r ( euf //</ . / // h ttj / m'lofuJ, pricr ! ; TMUr4 f> IU DIVItOfHCHT mimtlM IK ADAM SrRI I r. tO\OON. WC2 ffkr*iw*l. t fiJorf. It4fid. 4 Irkf***tor K'krtAill 4l7t ftltof N f ktofrt f I < 1*4 Ait*--U> AfMJikn un^w-i' **g?*?*f!i *!! .1 r