Document 91GO5YBy7Q3GL0a1xDwjn2Z2q

Lead waterproofing adds space to capitol building Rising majestically out of the rich central plains along the ^ est bank of the Missouri River is a building which. were it not for its location, might easily be mistaken for our National Capitol. It is, however, the Capitol of the State of Missouri in Jefferson City. The building is the state'4 third "permanent" Capitol, two previous State Houses having been destroyed by fire. Native Missouri limestone and marble were used in its construc tion. The building, started in 1913 and completed in 1918. was designed by the New N ork architectural firm of Tracy and Swarthout. Soon after occupancv. it became a Mecca for residents as well as tourists from all over the country. The building re quired 310.000 cubic feet of stone, more than 4.000.000 brick and 5,200 tons of steel. This tremendous w eight was supported by massive columns and concrete piers that extend down to bedrock. More than 50 years of weathering and constant use left the stairs and promenade? in a had state of repair. hen it was decided to restore these area-. Bernard McMahon of Clayton, Missouri was selected as the architect by the Board of Public Buildings. The Missouri State Board of Public Buildings consists of Governor ^ arren E Hearnes. Chairman. Lieutenant-Go\ernor Thomas F. Eagleton. Secretary and Attorney General Nor man H. Anderson. Member, under the direction of the Division of Planning and Construction. John D.Paulus. Jr., A.l.A. Director. The project was to The concrete substrate is painted with a bituminous coating compound before the lead 15 laid ever it This prevents the tree lime m the concrete from corroding the lead. Genera! view o* the reconstruction work in progress on the South staircase Forms for D mg of the new concrete stringers will be noted on the right of the photo The lead over the forms are built is coated with a bituminous compound to protect it from free i ,, ^ the cement. ,iaie 'p be handled in four stages, starting with the East approach which has been completed. The second phase called for the restoration of the main staircase on the South side of the building. This stairway ha? 45 steps which were resurfaced in white Carthage marble. Architectural plans call for sheet lead waterproofing Original), the elair. \.ere constructed over space that remained unoccupied because of dampne.-s and mildew, idea] perhaps for mushroom cellars, but not for human habitation. In planning the reconstruction, architect Bernard McMahon recommended the use of sheet lead to waterproof the area. This provided an additional B.OOfi sq. ft. of air conditioned offi< e spar-? and 6.OQ0 sq. ft. of dry storage area. The genera! (untrue tor for the job. E. G. Linbardt of Jefferson City se lected Larry Goad & Company of St Louis to do the lead work. An 8-lb antimonial lead sheet was used for the waterproofing membrane. A total of 70 tons went into the South ap proach area, reaching from the street to the portico column line. Before laying the lead, the concrete substrate w a- painted with a bitumi nous coating compound. All lead joints were burned to preserve tW integrity of the membrane i see il lustration). Reglets were cut into the column bases before the lead was Hashed into them. Existing dowelwhich came through int* tin formestep4 were capped with lead slreves and used to h<<ld the new stnnuerin place. These concrete stringer? were poured dirrctlv *m top uf th> sheet lead waterproofin'1. Tread- and ri-ers rested direct!', upon them after plaiement of the mortar setting bed Thev were held in place h\ means of dowel- and restraining angles placed at intersaG. The sanm de-igj. will be- nsi-d in the rebuildm. u the Monumental -taifasi- of tie W es: side <4 tie building Vt-irk on. tm- en tire project will be hni-hed in 19o8. me sheet lead was cs^efu'o )omeC by leap burning to provide for mtegMy of the water proofing membrane Surface of the lead is cleaned before the weid is maoe Lead sleeves mace from pipe wet weloee over exist-ng cowe-s tha- extent tee concrete to assure the complete wde'P'Oofmg of the area unde- tre steps > m progress on the South staircase. Forms for pou. noted on the right of the photo The lead over w(3 'tuminous compound to protect it from free lime j|. cted ned **w . ars. In 'tret the the nal lected Larry Goad & Company of St$C Louis to do ihe lead work. An 8-lb* antimonial lead sheet was used for'^ the waterproofing membrane. A total' of 70 tons went into the South ap proach area. reaching from the street to the portico column line. t Before laying the lead, the concrete substrate was painted with a bitumi nous coating compound. All lead joints were burned to preserve the integrity of the membrane 'see il lustration i. Regiets were cut into the column bases before the lead was flashed into them. Existing dowels which came through into the former step:- were capped with lead sleeve* and ued to hold the nev\ stringers in place. These concrete stringers w.erc poured directlv on top of the sheet lead waterproofing. Treads and riser:- re-ted directlv upon them after placement of the mortar setting bed. They were held in pla^e by means of dowel- and restraining angles placed al interval?. The same design will be used in the rebuilding of the Monumental staircast of th<- ft est sidt of the buildins. ft "rh on the en tire project will :e finished in 1968. LeaC sleeves made from pipe were welded Over ex'st.ng oowels that extend through the concrete tc assure the complete waterproofing of the area under the ste, Four coat lead paint system p-otects bridge against the elements The latest addition to the Jackson ville. Florida landscape is the Isaiah D. Hart Bridge that connects the main section of the city with the East bank of the St. Johns River. It af fords local Jacksonville traffic easy access to Duval County residential area and nearby beach communities. ft ith a main span of LOSS feet, the bridge has a minimum \ertical clear ance of 135 feet above mean high water. It boasts of two. 28-foot roadwavs separated by a four-foot med ian. It is currently carrying more than 12.000 cars a day. Construction took 73 months from the lime the first pile was driven to the last stroke of a paint brush. In painting the bridge, to protect its lO.OOU tons of steel from the tough sal: water en\ironmenl. the painting sub-contractor. Lnited Painting Con tractors of Minneapolis, used a fourcoat lead paint system. This will shield it from the elements for years. In fact, this job won't need redoing or require significant maintenance for as long as a decade. Basic lead siiico-chromate was the corrosion inhibitive pigment used in each of the four coats. A brown primer was shop applied, followed by three field applied coats. The first of these was buff. The next two were green, with one tinted to provide a color differential between the coats. Each coat was applied to a wet film thickness of 2.5 mils. Total dry film thickness was a minimum of 6.5 mils. The graceful span, which was open ed to traffic in November of 1967. is almost half a mile long. It was de signed by the consulting engineering firm of Svedrup & Parcel and As sociates, Inc, The substructure was constructed by B. F. Diamond c:' Savannah. Georgia and the super structure was fabricated by .Allied Structural Steel Co. of Hammond. Indiana and erected bv its Industria. Construction Division of Minneapo lis. Minnesota. coats was tinted tc proviae a color differential ry - , -r *%l ,-,-,,jr ; .. --Sr'" - ; ' - ... 4.- ' Wi I; THE ELECTRIC AUTOMOBILE. FACT OR FANCY After the first electric vehicle was built in the United States in 1888 by an obscure inventor, Philip W. Pratt, its popularity surged fox a short time and then waned. Its decline was un doubtedly due to limited range and relatively slow road speeds. Until recently, the electric car was much like the weather--every one talked but no one did anything about il. For years, however, the electric car has had a sort of love affair with the public press. According to Nile LingTen. writing in the April 1967 issue of IEEE Spectrum, more than 1,500 articles appeared on the electric car during the period from 1928 to 1966, roost of them holding forth great promise for better things to come. A New Lease on Life for Electrics During this 38 year period of stag nation. nothing has done more to re vive interest in electric car develop ment than recent advances in batterv technologv. solid state controls and motors. As a result, the Ford Motor Company has recently embarked upon a serious investigation into their practjcabilitv. Research Program Started Working with its research and manufacturing facilities in Great Britain, where over 40,000 electric trucks are on the road, Ford estab lished the following design para meters for a prototype unit: An overall size that would re quire minimum space while traveling or when parked. High maneuverability for easy access to small parking spaces. Quiet operation. Minimum contribution to air pollution. Low initial and running cost. Simplicity of operation. The company felt that the electric car offered unique advantages in ur ban and suburban use and that held experience should be forthcoming from which precise judgments and evaluations could be made. The pro gram was started with the full aware ness that electric car development would require a long research period for the technologv required was new to Ford as well as to the rest of the industry. The initial step in the program was to design a feasible, limited-purpose vehicle that would eventually lead to a commercially practical electric car. The first experimental prototype model, two of which were built, is known as the '`Comuta.'' One unit is undergoing tests in England, the other in the United States. The cars are designed with an overall length which permits three to be parked head on into the curb in a space normally occupied bv a standard size vehicle. Lead-Acid Batteries Power Prototype The four 12-volt. 85 ampere hour capacity lead-acid batteries are used as a power source. Thev are located beneath the front scat. Two are placed on each side of the car to maintain a good weight distribution. Two 24-volt. 5 h.p.. electric motors are used, one on each of the two rear wheels. They are series wound, dc type. New Control System Devised To conserve battery current and provide maximum traction, a new svstem of controls was devised cmploving the latest in circuitrv which includes solid state thvristors. Based L IA 2 t52 3 BILE... and Great ectric estabpara* !d rewhile easy ices. vehicle that would eventually lead to a commercially practical electric car. The first experimental prototype model, two of which were built, u known as the "Comuta." One unit is undergoing tests in England, the other in the United States. The can are designed with an overall length which permits three to be parked head on into the curb in a space normally occupied by a standard sire vehicle. Lead-Acid Batteries Power Prototype ertnc r. urfield ming and pro' arement riod new the The four 12-volt. 85 ampere hour capacity lead-acid batteries are used as a power source. Thev are located beneath the front seat. Two are placed on each side of the car to maintain a good weight distribution. Two 24-volt. 5 h.p.. electric motors are used, one on each of the two rear wheels. They are series wound, dc type. New Control System Devised To conserve batter)' current and provide maximum traction, a new system of controls was devised em ploying the latest in circuitry which includes solid state thyristors. Based elements similar to those used . transistors, they provide for high jrf>quency on-off switching of large ffectric currents. Unlike traditional electric vehicle controls that use wire .ound resistors or "carbon piles," thyristors dissipate very little cal energy in heat and make to 20', more of the battery's stored energy av ailable for propulsion. The thyristor system utilizes a serjfS of short duration pulses of full batterv voltage that are applied to the motors. Electric current is smoothed 0ut tv supply the motors with a con tinuous but lower voltage directly from the batteries. An accelerator pedal controls the rate of pulses and varies the supply to the motors. This gives control of the speed, accelera tion and climbing ability in conjunc tion with the speed-torque character istics of the motors. The controls of the "Comuta" confist of three main units--a contact, a power circuit and a logic unit. The contacts are controlled by the for ward. neutral and reverse selector lever. The accelerator is arranged to bvpass the thyristors when full bat tery current is needed. The power cir cuit consists of the thyristor pulsing system while the logic unit governs the power circuits and the safety controls. Lead-Acid Batteries Make Prototype Practical The four lead-acid batteries under the seat are connected in series and supply the car with sufficient energy to give it a range of 40 miles at a steady speed of 25 mph with an aver age load. The "Comuta'* features high-low beam headlights, directional signals, windshield wipers and wash ers as well as an efficient cooling and heating system. It has independent suspension for each wheel. Having no clutch or gears, the "Comuta's*' oper ation is completely automatic. Don't be disappointed, however, if you fail to find one of these "Com ma's" in your local Ford showroom for some time to come. Ford openly admits that this early version of the ``Comuta'* is just one of the first steps in the development of a practical electric car with probably many more prototypes to be built before it is ready for the riding public. Chassis and lead acid batteries of the experimenta pb international Lead Power Year 1968 3rd International Lead Conference The 3rd International Conference on Lead will be held on Septem ber 18 through 20, 1968 at Ven ice. Italy. Site of the conference will be the world famous Excelsior Palace Hotel on the Venice Lido, where the technical meetings and exhibition will be held. A fleet of motor launches available at the hotel will be placed at the dis posal of the delegates to provide access between the Lido and Ven ice. The meeting will be the cul mination of a special campaign that was mounted by LIA with other world lead associations to promote the use of lead-acid bat teries under the banner "LEAD POWER '68". A part of this pro gram was an international compe tition, awards for which will be presented at the Conference. An other outstanding feature of this 3rd Conference will be the award ing of the newly created Wilhelm Hofmann Memorial Prize to the author of the best technical pa per, Previous sessions were held in London in 1962 and in Arnhem in 1965. The meeting will include dele gations from lead producing anc fabricating companies throughout the free world. The meetings will be set up in three groups. Cable, Battery and General, each of which will consist of the pre sentation of papers, discussion periods and plant visits to various Italian lead production and fabri cation facilities. A total of 30 papers will be presented by some of the free world's outstanding authorities in their field. Copies of these will be sent to ali regis tered delegates prior to the con ference. Discussion from case histories of difficulties in the pro duction or use of lead sheathed cable, electric car developments to a research seminar including a review of International Lead Zinc Research Organization (ILZRO) work. While the official language of the conference will be Eng lish, simultaneous translation into French, German and Italian will be available for all throughout the sessions. Copies of a provisional program together with hotel reservations and conference registration forms can be had by writing directly to the Lead Industries Association, Inc., 252 Madison Avenue, New York, New YorK 10017. Lead Sheat to carry Republican ( /; ^ hen the Republican National Com mittee chose Miami Beach for its 1968 Presidential Convention it marked the first time the Party had selected a Southern site. The Demo crats. more than a century ago. held a comention at Charleston, South Caro lina which was adjourned in a dead lock after 10 days. hen it re-convened in Baltimore two months later, two slates of candi date? were nominated. The Northern faction nominated Stephen A. Douglas of Illinois and Herschel V. Johnson of Georgia, and the Southerners. John C.. Breckenridge of Kentucky and Joseph Lane of Oregon. The Republican con tenders that year (18601 were Abra ham Lincoln and Hannibal Hamlin of Maine. Now. in this era of instant commu nication, everyone can be right on the Comention floor when the Republican hopefuls are named. Events and color generated throughout the entire four davs will be seen on television screens from Hawaii to New A orb. from Alaska to Texas the instant they hap pen. Communications satellites will carry the Convention practicalK all o\er the world. Existing communications facilities from the Beach although voluminous were not adequate for such a conclave. Prior tu this, some network shows emanated from the anu But .now. all of the Nation? Tk web'. u?inc dozens of camera' in aim mam locations, will be d>-' noma upm Miami Rea'h to beam tne hap' p-mmc' to world-wide \ieuinc audi ence'. Add to this the mwhd require ments of the radio networks w iri shmens. independent news srr\hes. and those of the delegation? of \ariou> ?tates -- and the communica tions problem becomes almost in surmountable. Southern Bell Telephone Company, to meet this challenge, undertook to complete in ten months the facilities to do a job that would normally re quire two year? to install. From all over Florida and elsewhere in its ter ritory it assembled a task force of skilled men and women and went about the mammoth job of de\ising time tahles. cutting production times and expediting procurement of needed materials. ork around the clock, by different shifts, became the order of the day. They were joined by other Bell Sys tem men of the Long Lines Depart ment of the American Telephone and Telegraph Company and the Western Electric Company. Bell System's man ufacturing and supply unit. A major segment of the project called for the laving of a ten mile cable from the beach to the mainland as the main communications pipeline. This was needed to augment other facilities that connected to the Con vention Hall and all the major hotel? into Bell's regular facilities in Miami, hi record time. Western Electric s Hawthorne ork? in Chicago pro duced -4.206 feet of coaxial cable. 2.500 fCet of which was protected b\ a lead sheath. To do this they cut tin norma) nine week production sched ule.with an all uut effort, to two and a half wreks. After the cable, intended f<r submarine >er\ice. wa? sh-atfe-d with lead, it ms - sent to W L s Haltinv<r>- Work? where steel wire wa? ap plied and then neoprene coated. A thinker la\er of bad is normally ap plied to cable to be wire armored be- 5 Cable yer lion News Com1 r it? i ir \ had lernotrld a Carodead- more andiibern uglas on of hn C. '<eph eon\brairi of nmun the lican -olor four reens ' rom if r!' >us Cut .id:ore ire t f i' various states--and the communic*. tions problem becomes almost ijj. surmountable. Southern Bell Telephone Company, to meet this challenge, undertook to complete in ten months the facilities to do a job that would normally re* quire two years to install. From all o\er Florida and elsewhere in its ter- ' ritorv it assembled a task force of skilled men and women and went about the mammoth job of devising time tables, cutting production times and expediting procurement of needed materials. Work around the clock, by different shifts, became the order of the day. They were joined by other Bell Sys tem men of the Long Lines Depart ment of the American Telephone and Telegraph Company and the Western Electric Company. Bell System's man ufacturing and supply unit. A major segment of the project called for the laying of a ten mile cable from the beach to the mainland as the main communications pipeline. This was needed to augment other facilities that connected to the Con vention Hall and all the major hotels into Bell's regular facilities in Miami. In record time. Western Electric's Hawthorne Work? in Chicago pro duced 4.200 feet of coaxial cable, 2.50*1 feet of which was protected bv a lead sheath. To do this they cut the norma) nine week production scheduh.wiib an all out effort to two and a half weeks. After the cable, intended fur submarine sen ice. was sheathed with lead, it was sent to ^ E s Balti more orks where steel wire was ap plied and then neoprene coated. A thicker laver of lead is normal!) ap plied to cable to be wire armored be- ^use of possible crushing effects en countered when the steel armor is put in place on the lead sheath. The steel gave the cable additional mechanical length to protect it from physical damage when submerged. The fin ked cable measured more than three inches in diameter. The wire armored )P8d sheath was specified bv Bell's jngineers as the best possible proteclion for the underwater sections. Permission to lay the lead sheathed portion of the cable across Biscayne gay was granted by the U. S. Army Corps of Engineers. It was placed in the Bay north of the 14th Street, Vene tian Causeway to a minimum depth of 18 feet under the channel. The fleet that did the job included a large barge upon which the reel? of cable were mounted, a towing vessel with a crane and a smaller work hoat. The task of splicing the cable was done in mid stream by Bell's experienced cable ^rrVp"dird""rr.ra men. The new cable can transmit 24 tele vision channels and 100 radio-audio programs simultaneously. Require ments for the working press anc others which will include up to 32f teletypewriter machines, more thar. 6.30fi telephones. 30 switchboards and complete facilities for sending w ire photos will be provided bv the cabh , The Republican Convention of tn:.| year will have the best coverage thrr it is possible to achieve through In most advanced mass communicationtechniques of the electronics age. This is a far cr\ from the two-city, oneebannr) television network that linker * New \ ork to Philadelphia and carried the proceedings of the 1940 Republi can Convention when Wendell Wilkie won his party's nomination. ,<ai television cab tnc m Chicago ana armor rushed by flatcar tc M contains video circuits which w the Republican National Convention at ^,th Southern Bell's TV Op Center i Mu -bii !"d.45" hh.*"a on' Just north of the Vere ,er Causeway, which connects the mainland e;th M.anv Beach, is the route c' the new lea sheatnec cable 7 QUIET: GUEST ASLEEP VThile the words "mouse and "lead" are far from synonymous, the old savin tr "Quiet as a mouse' mar soon be replaced bv "Quiet as Lead.'' As a result, one of the latest advances in the use of sheet lead is a? a sound proofing harrier in modern building construction. Today, many ar. meets have adopted the practice of using thin sheet lead as plenum barriers and as over-the-ceiling barriers for sound attenuation. Few recent appli cations pro\e the effectiveness of this use as much as the installation at Ca nadian Pacific's Hotel. Le Chateau Champlain, in Montreal. This hotel, is part of a complex th* co\ers a square city block. It provi^ 640 rooms and suites for visitors a variety of public rooms and rest*u rants. The center has a 28-story off1Cr building, a shopping promenade. 4n 850-seat theatre and five levels underground parking space. In designing the hotel, the arch] tects. D'Astous & Pothier, found j| necessary to include machine roon^ on the 3rd. 19th and 84th floors. ThU left a problem of noise isolation on these floors from the rooms above and below. To solve the problem Goodfriend Ostergaard Associate*, consulting engineers in acoustics, rec ommended the use of 3-lb. sheet lead in a special suspended acoustical ceil ing hung from the structural concrete slab by spring and rubber isolator*. The ceiling assembly, was insulated from the walls at its perimeter bv 1 ^ "-thick glass fiber strip calked in place. A total of 30.000 square feet (45 tons I of sheet lead was used. In order to take full advantage of lead's "limpness'' (a prime quality in sound attenuation ) the sheet lead was laid loosely on top of the ceiling construc tion. To cut off "flanking paths" (acoustical engineer's term for a sound leak l the lead was turned up and fitted snugly against all perimeter walls. Finally, in order to damp resonance within the plenum itself, a 2"-thick fiberglass mat was laid on top of the lead. The plastering con tractor. who did the lead work, was St. Laurence-Ribeau of Montreal. Proof the the sound attenuation capability of the ceiling is evidenced by the fact that, since the hotel has been opened, not one guest in a leadtreated room has complained about noise from the machine floors. To achieve a maximum degree of acous tical separation at the connecting doors of 120 rooms, these doors were constructed with 2 Mb. Pad shirts, one laminated under each face ply. In effectively reducing noise trans mission. the sheet lead barrier pro vided the necessary sound control at an economical tost. $ Tad' old ma\ ad." rices andding :ects .sing 'iers for pplithis : Cateau QUICK-CONNECT LEAD PLUMBING CUTS R0UGHING-IN TIME This hotel, is part of a complex covers a square city block. It pro\ 640 rooms and suites for visitors a variety of public rooms and rest rants. The center has a 28-story ofi building, a shopping promenade, 850-seat theatre and five levels underground parking space. In designing the hotel, the an tects. D'Astous & Pothier, found It necessary to include machine roojj* on the 3rd. 19th and 34th floors. left a problem of noise isolation these floors from the rooms abo*^"' and below. To solve the prohl^J-:Goodfriend Ostergaard Associatei/'J consulting engineers in acoustics, reo*?'ommended the use of 3-lb. sheet W;. in a special suspended acoustical cefl ing hung from the structural concrete" slab by spring and rubber isolator*' - The ceiling assembly was insulated from the walls at its perimeter by ^"-thick glass fiber strip calked in place. A total of 30,000 square feet (45 tons) of sheet lead was used. In order to take full advantage of leafi "limpness" (a prime quality in sound attenuation ) the sheet lead was laid loosely on top of the ceiling construc tion. To cut off "flanking paths*1 (acoustical engineer's term for a sound leak) the lead was turned up and fitted snugly against all perim eter walls. Finally, in order to damp resonance within the plenum itself, a 2"-thick fiberglass mat was laid on top of the lead. The plastering con tractor, who did the lead work, was St. Laurence-Bibeau of Montreal. quick-connect lead drain syst for chemical laboratories was ,phed in from start to finish in less , Workman prepares than eight minutes, and no burning i welding i or soldering was necessarv. Only one man was required for the joh, freeing a helper for other tasks. As in the case of a typical labora tory service ledge, shown here, the pipe and fittings were shop fabri cated. The lead pipe can be cut to size for joining in the field, however, using a portable flanging tool. The components go together easily and the assembh carries a 50-year guarantee. Two lead flanges are brought together, under pressure, by brass unions to form tight, leakproof joints. Thus, lead is the only mate rial exposed to the corrosive wastes. And -- materials and installation costs are low. Minor errors in pipe length can be corrected by bending the lead to fit. minimizing roughing-in costs. Any part can usually be quickly reshaped if deformed as by dropping. ""k * *"* `TMP"n 'abr,,r' then b- The pipe is ."Stalled between the ' fl,,in. , ... 4; 1,. lengths ot leao P'PF tees of the second and third sink is*.. -- - -- i- Proof the the sound attenuation capability of the ceiling is evidenced by the fact that, since the hotel has been opened, not one guest in a leadtreated room ha? complained about noise from the machine floors. To achieve a maximum degree of acous tical separation at the connecting doors of 120 room?, these doors were constructed with 2 1-lb. lead sheets, one laminated under each face ply. In effectively reducing noise trans mission. the sheet lead barrier pro vided the necessary sound control at an economical cost. t * _______ a-J T fTl a 6: Two more sections are joined and fined between the tee and the elbow 7- A trap is then added and an adapt 7- At^ap connect the assem 'to an outlet- .. - . From sun to finish, the complete rOuSh m took nder S minutes I 0 VIS, LEAD MAKES THE SCENE Provides Positive Flash Action for Polaroid "Swingers" Th-s precision, die-cast lead weicht assures positive flash gun actio*. "Shutter bug' or not. eveTvone has. heard of Polaroid inslant picture cameras. Especial!) well known are the popular priced "Swinger" and the recently introduced "Big Swinger." ^bile low in cost, these fine cameras arc precision engineered to vield ex cellent photographs of extremeh good qualitv. One of the first design prerequi sites recognized b\ Polaroid engi neers was the need to make the cam era as foolproof as possible. It had t he fme that anyone- wh>> can read and folio* simple instruction* would he able to operate faulth-ssh. Both models of the "^wineer" achieve this goal. Built-in safeguard- assure this. Most outstanding of these "goofproof" features is an integral photo meter for daylight exp'-ures. Rv turning an adjusting knob until a clear "^ES is seen in the lower sec tion of the viewfinder, the lens open ing is automatically set to give cor rect daylight exposure. If the light is too dim for picture taking, a ebar "'1 ES' won't appear. In that case, the user mereh pops a flash bulb into tincamera s flash sun. on the from of the camera lens board, and snaps awav. The camera converts from day light to flash operation with no other adjustment. The ?am-- knob i? turned to a footage scale for thr camer.ito-subject distance and. in so doing, thr lens opening b adjusted for cor rect flash exposure at that distance. Polaroid designed a simple but ef fective system to svnehronize the flash to the r-hutler. A direct mechanical linkage clones the switch that fires the flash bulb. To make certain that the switch does not "hang up" and posihlv fire the next bulb when it U in serted. the engineers added a preci sion die cast lead weight to the pan to mahr- sure the switch will alwaya return to the "open" position. Lead was chosen because of its high weight to mass ratio. The supplier of the tiny weight, measuring 14 " x 1 j r ". is Lead Fabri cators. Ltd. S" critical is the function of thi* casting it is made with a vveiuht P'U-ranor- of r. 0.040 gm. and a size loleranc f of ri: O.002U As is often the case, lead plays an important but unseen role. Here it is used to great advantage- to asurr positive adiun for the ">wingprs flash gun so that photographer- obtain perfect pictures every time. 10 LIA26529 'm until r secupen corjht is clear e. the u the nt of snaps . dayother irned :riera :"ing cor anee. it effla-h mical * the flash bulb. To make certain that the switch does not "hang up'' and pos sibly hre the next bulb when it is in serted, the engineers added a preci sion die cast lead weight to the part to make sure the switch will always return to the "open position. Lead was chosen because of its high weight to mass ratio. The supplier of the tiny weight, measuring \ 3 jc"- Lead Fabri cators. Ltd. So critical is the function of thir- casting it is made with a weight tolerance of --0.040 gm. and a size tolerance of ir 0.0020 As is often the case, lead plavs an important but unseen role. Heir it is us<-d to great advantage to assure positive a< tion for the "Swinger s?' flash gun so that photographers obtain perfect pictures every time. SEALING GLASS KITS A research and development kit containing eight Ion mehing glasses for glas> sealing experimentation is being distributed bv Owens-Illinois. Inc. Such glasses, called `'Solder' glasses are used in the manufacture of television tubes and sealed beam headlights. Lead oxide often plavs an important role in ''solder" glasses. It provides a lower softening temper ature. good electrical properties and has a minimum effect on thermal ex pansion. brations tra\el to the end of the machine's transducer where the working end of the Unit is moved at 10 MHz. producing the taps that do the riveting job. SOLDERING NEEDLE RIVETING WITH SOUND? Brain child of Western Electric's bio-mechanical engineers, this indus trial style electric chair was designed to reduce fatigue and increase oper ator efficiency. It is used to speed the wiring of a 9'x4' digital rack at ^ E's Burlington, North Carolina shop, The unique lead-acid batterv powered chair enables the operator to perform all the wiring operations at a com fortable eye level. Weighing about 15 lbs., this newsonic riveting unit delivers thousands of taps almost instantaneously, to re place a single blow that is the equiva lent of 10 tons. Developed at the Ohio State Lniversitv Sonic Power Laboratory, the heart of the new device is lead-zirconate-titanate, a piezoelectric mate rial that converts electrical energy into mechanical vibrations. These vi- in this age of miniaturization and microcircuits, the development of a soldering needle is only a logical step in the sequence of events. Designed by the Caig Laboratories, the newsoldering device is intended for use under microscopes and in applica tions involving small space tolerances. The weight of the unit is only 4.5 gm and has a power consumption of 5 watts. LEAD INDUSTRIES ASSOCIATION, INC. CHANGE OF ADDRESS OR NEW READER Use this side of the coupon if you have recently changed your address. Attach address label from mailing envelope. II you would like to be added to the mailing list for LEAD, please fill out lower half of coupon. ^ CHANGE OF ADDRESS From Name, Title Company Street City, state, zip code C ADD ME TO YOUR MAILING UST (please check one) PLEASE CHECK INTEREST - Painting ~ Health & Safety ' " Design & Radiation Engineers ~ Ceramics . ~ Chem.ca! Engr<, l Batte-y Power City, state, zip code