Document zQm6pKn5oknRezB06d7wqB77m

Buffetiv of The American CcratnicSacicty--'Twky Soda asb improves quality of boih die luiei and die how tite. Experience at Uses plant has. wnphaxired an even n>wr interesting poise namely, ike property of soda arb of de* prrariog the maturing Usopr*tre in firing, The material used has an extremely narrow firing range; about six euurses of brick * lie bottom of rmy Vila were lonncrly m Sight colored and toft is U, be praelk&tty unsalable. With soda ash, te different percentages of treatment are weed; the heavier treatment it tried ea the required prqporiioa of tieproduction toset six eouncs in eacb kiln, and certain wands in the drier are reserved fur these bride These brick are also testified by a scratch mark on the back. Instead of the capacity of each kite being cut ap proximately 4300 brick, (he kilos bow turn out thrir ftftl dapadty of folly fired briefc; tie brkk from the lower courses are as dark aad hard as those from the higher eecreea. The shrinkage. furthermore, U * uniform as tie color. Tie probable vsduloess of such a procedure sa other plans*, in regard to production aa eB as cost and quality, is fcatvreHiog. Another applRation of this same procedure suggests itself for plants where sHgfat or no actual losses oecur through underfired brick in the tower portions of the kilns if the meturiog temptnture of ware a selected porrioss of tie kiln may be reduced by similar differential soda ah treatment, over-all firing time may be reduced. Lens beat and consequently less time wkQ be required to mature the lower courts of brick which carry the hearts soda a*fa treatment. Time saved at the last end of a firing lends t wcnb-luk fad Bring, and any saving of firing tone i* automatically an bxaeatem firingcapacity. ''V^.Coodwleo *T2re Av^obi^epcmptoare typical results obtained Uthe use of soda ask ba the Baiker-Tmog process esd rtpr* sest a tride variation of raw materials and plant proev dure as well os of geographical location. Defefiopse::! along the Uses dismissed nt never of greater important* than at the present time when high-quality praduedea 2: minimum cost is urgently needed. Socrar PaocwutCowravv Snowt-M, Saw Yo it Ba" There ar*t I *sd textile snbdiridcd in Bed most get l coarser form batteries. *d tfen mi air-cot i starting point ' TcatSe fiber* i the touiiitaotvi fawfidmg up a ihnth that a ty. Both ftei | AH1 the 1* { jfiuolten^aas i jlgimsmuitiBt [ /w Staple tea i htefriprMttj | p--imit fibers t RBERGLAS; SOME PROPERTIES AND NEW APPLICATIONS' By F. v. Tot*e Amt*act Fibergtes tft produced in two baric forms, namely, ** a woof and asa textile. There are three rarities of wool: <]) thermal-fcaselation wool, the starting point for a targe number of insulation products; (2) bonded mat wool, used in the form of a retainer mat in electric storage batteries; and (3)air-filter wool, usedin therieuiug tod condi- fhaiat of rtr. Tenltefibo* erne# Iwo fypes, reeMlmjoos aiJ slapk. These two types represent startiog points in the construction of numerous yams, tapes, and fabrics used lor electriml insulation and chemical filtration purposes. Other applications range * from use as wickiag for ot) lamps and stoves to use as a pipe lagging material, The versadUty andutility of FitagUt are a consequence of the chemicaland physical proper ties of the original fuiic fibers ard the bfgfe adaptability of the fibers for pndrtm&jjsrd orderly wgarUted arrangement. FSbcrglaa can be used profitably wherever (l) eleetririty is generated, transmitted, or used, (3) air is cleaned or eondktoned. (3) .best ts conserved, controlled, or excluded, and (4) fabrics are needed to withstand beat, rot. dampness, deoay, or chemical attack. Stew and future applications of Fibergbs include fu use or tfevrhpwnf at witisag-iB-reMiittlmS'-witk.pcrt taou u> iced solutions, through controlled capillarity, to the roots of growing plants; (2) a coabisarion imulaat and surface finish in the form of a sew strong, rigid, lightweight board; (3) a new low-temper*!are insulating medium ta the form f an asphalten closed rigid bat; W n surgical suture and tracer yam in surgical sponges; and (5) a dec orative fabric. LVd as an effective rcp/acemcnr material /orcork, pookrrtxu csbestos, alomtmien. and mica, Fiberjtas Is becoming increasingly important as a strategic mate* rial. 4==33]V Wool Rks W fibers a the'jwel aatm^asd of prodsk tfc* to desired ^ appfiref!oe le^tale hand!* reWorcs ot tlf tvavfyn. haHPu, and it edwrpmdsrtt i 1 The wroJprcK l . tbtln *rh^b (! I e^^newSai tb | *t tbr other. S i &***' J **igpec<*U% I ^cfnrwaees % {^ 4 ^ 6b*** ifaer tapl h letiodcfioa Rnowledge ol oew materials. the jobs they will do, and bow they iU <lo them U an ali'impon&nt factor in tnaljng the piost effective use of research, engineering, and designing rime. Ifaere are njiny materials for which such tafonnatioo could proStably be summarised at the time. This i> panscular!)* dcssrabic >0 tlw: <ne of * Freseoted at the Forty*fourth Annual Meeting, The Americaa Ceramie Society, 1 n<,, Ci nciunati, Ohio. April 22. 1942 (Class Div^on), Received May IT, S42 Fiberglas because <4 the rapidly eapaodlng scope of *' s Beso*. Mors p **4veappheatfon and the effetrdarri difficulty of I'tvpesg iV needre [technical man informed as to what this unique material ess ^*Peraido or is doing tochoolugmtty. In 1931, there was but o^r Ob to ! *^-tdf'*m t!Fiberglas product; tsday, 333 Paratc FibcrgUs produfi* are manufactured, and Urge quantities of basic fibers an-' AB . yam* Are eoruribu'ing ro tfse value of a <ride variedy o' ldcpcndcn11>* manafsettled artfries. Glass is an o*d and friihlul ser\-aat of mankind, and >* 05CoC*o"!wvj Bo`VusUfihI this fibrous foitn, relatively newoQ the industrial scene. ` continues to fulfill its traditkma! rrrfe. ,2ir^w fh7 4t, Ci Vul.22. So : WV-03380 Fiberglos: Some Properties and Sew Applications 61 IL Srtk **4 yent and Their Production ch*Bic*Uy on a spindle which travels at a speed (4 a mile a "gl*** art two fiasie forms of F'iberglas. vis., a wool form ad icitilc fiber form. The wool form may be further fAA.4^ into three ekmestal fibers: (1) a fine fora* k4 dost generally lot thermal tabulation. (2) a slightly iiHiar fons used as a retainer mat in electrial storage bMteria, ** (3) a mwh coarser form used for air film^ }b ai<6t*nfaf systems. Tie first ol these is the Uirtinf*pohX for a large variety of fasufaU-OB products. TcatBe fibers likewise eaist in two elemental forms, viz. ehc cootlftuotts fiber and the staple fiber, which are taed is bo3d3eg tip a but* Bursbo1 and variety of yares and threads that an subsequently woven Into fabrics ol wide ^SSvt, Both fibers are aueb fitter than the thermal wskJ minute or even higher, J-cogtba <4 the filaments are limited only by packaging requirements. The individual filaments in the most commonly made continuous strand _are 0.00022 in. lo diameter, although hereagain this diame ter eaa be varied considerably os either side according to the characteristics desired in the final product. Small amounts of lobricssts aad coatings are used oa both the staple fibers and continuous filament strands. Tbs materials, usually starch or vegetable sod mineral oils, facilitate the forming operations aod keep the indi vidual glass filaments from nibbing together. This ap plication Is important, for the stntegih of glass fibers Is redated tf the ratfaces of (be fibers bccorSe scratched. fiat. AS of the basic fibers are produced by the attenuation <<) Ymy fmolten glass as it issues from small orificesat the bottom at gtaasmeltirtg tanks or furnaces. In all varieties of wool aid tuple textile fibers, the attenuation is produced fay ^h^rctfure jets of steam ora; the attenuation of coa- Tbe yarns that go into the manufacture of fabrics art built ep-froa the original staple slivers and continuous filament strands os standard textile machinery, the latter rajalria* bat slight modification. Original caotiouoaa "~jfnn~r fibers k produced by mechanical drawing at Ugh strands are twfctad and plied together lo give any desired .ax*. -zMor (Q_Voef Ftben r: Vol fibers are reflected on a traveling conveyer which r mow* the pack through a series of automatic opezatkeu, yarn coastroetion, the fatterdependingon the service func tion tobe fuifiScd. Ordinary, yarns will consist of from two to twenty original strands, and the heavier construc tions eomjaKxdy involve as many as ten separate twisting and plymg opemiosa. TjgtMture and cumber of which depend on the particular Tbe original staple sliver h converted into yam fay \ pradset to be made. These processes include faftrteuka. the appScarioa of fehufing agent, compces- ' tfiijp desired density, the curing of the binding agent, . .tfi^kppticelioa cf special adhesives and coverings to iState handling, and cutting to desired *, Some of - ttii products an complete for use as they are taken from draftrag aod twisting process patterned after worsted yarn methods. Yams of various degrees erf fineness ore produced; tbe degtui of.drafting is governed by the de* sired fineness. The coarsest staple yamsare madewithout drafting. ftFceoveytr. The material often Is but scmtprccamed, Wmr, and it servesas a raw material In the buildfag of afterproducts (see Sections Z1I and IV). HU Proportion ProdaeU, and Application* (1) Properties Thewoolprocess eonrisuof a standard glass-tank opera- Tht great utility aad x'ersatility of nbergfas aric from Sao b whkfa the batch k charged in a conventional way a* K cad of the tank and glass wool fibers are produced a* (brother. Doth tbe staple and continuous pnxesses 4ftr_from (hr wool process ic that each involves tbe use (wo fundameacaj sources, viz.. (1) (be pfayskal sedchemlcal properties of the glass from wbiefa the bask fibers are made and (2} (he adaptability of the fibers to organized formation aod arrangement whkfa makes possible the * collet io tbe form of marbles. Tbe glass marbles ; Vtfcspccud carefully before (lw? are fcmclied la special T fttetrie furnaces, buSding up of derivative products erf prescribed aod oact ing specification?.. Reduced to fibers, the properties that cbaraciriae,y1ass 0} &*ftfae I. -Sfapl* fibers ere collected in tbe form of a web of fater- ***rf fibert, oa a traveling belt from which they are sub- *lViUly gathered without twist, as a sliver (pronounced S**pk fibers average R to 15 in. io length; :*' , ortnnjoa variely averages about 0.00027 la. in _ More recently, both larger and smaller fibers ' ^t*rTBP^vded. a nd 1hey havc beco produced for special - ^T**8?*' * slight draft is gi*TM to the s)iverio tbe gatber^MPnwtiou (o orient the majority of fibers n parallel *^tmain. AU staple fiber rovings and yarns are Su turn *^**d bum this original staple sliver. > CMdbooMFiban Cwwioueui fiber* 3Tt made bv a different process. 7 he filaments. 102 or snote. aie continuous io lengi b. **** are gaifa-red into a strand. they are drawn me>HJ5 m general are retained, although some properties are modified considerably. Brittleness disappears as a prac tical coasideration aad is replaced by AeiibiTsty and resfliency. The (ensile strength of glass increases erlra* ordinarily as tbe *slu cf tbe unit or, la this case, fiber b decreased. Fibers with calcvfaud teasllc Hicogths as high as 2,000,090 lb.;sq, la, haver been produced fa tbe labora tory. Fibers of a sue used io regular cORtiauous-filaaieat production show tensile strengths of around 300,000 to SQQ.QOQ fb./sq. fa,, a value cooslderably mote than the tensiJr. strength of hard-dmwu steel piano wire. Glass fibers are tpcumlwisltblr, a property uhich is erf extreme importance in piactically all applkarions from (he safety sundpolat. High-brat aod electrical rcsisiaoee are responsible for tbe wide aj>piirabilii y of Fibergtas fa the eJectrtcal field. Tapes, yams, and fabrics used m tbe electrical industry ean safely withstand tcnsD<ra-tts up to !G0v*'F. i>2 Bulletin M The Amerieon Ccrcnric Society--Toakv The electrical properties of glass arc relumed in firmer fora and arc angittvtiled by ur cJ glasses tt>ltsian:to.lty free ofCroup 1 alkalis, Fificrglit- ric'ukal tai** combine high dielectric strength *<| electrical insulation resistanet sritfi estremefy low moisture absorption. psoSsobiy used *hcre*Kr tl'skeirkhy i- yrnreated, milted, used. (2) sr eksnni or conditioned. W heat t* conserved. emtiroUcd. or excluded. or (<T< fabrics us? needed to ifa*usd heat, rot. dampness, decay, tchetmatf acuefc, Density degree suriacn coodiito *n& the male purposes oot or IV* lb. per cu. sheets, mctal-st of predcienortH sulatritg aU typ .te ranges fro product. Start' tosolatioo are a 'Wi-iosulariftr' Fw. t,--Baste fibers used in the pfedoetkro ot FSiergla* product*. Top to* {U'r ic tight): cosjsauras filament Strand and p!e sliver; bottom row tf#r to right): hwwUtbn word, bonded mat Gfxv. and air filter wooL Fto. 3.--Corwimrous filament jsrw ou various typo of package Fie. a.--ra _ tine tope IVae ahmrat burn tbeorffio pfrn*. sreanri Fro. 2.--Carelulfy injected rttarbk** used in the flianufaerurc of resttic fibers Chcrckal durability I'Ctoines of increasing imitortane* when the glass surface is increased by filwriimg. X de gree of attack which o1d be rcgiisiblr: m a large article u a serious matter with a small fiber, so specks! glasM-.s must be employed according to the service londitiom. to !* eo* cooBUaed. Tbe thermal and air-filtering prgpmics "1 Fibers!** t3uh from its general fiber !orn) and mlaiitabil!' y ?<. form, ability and orgauired arrangement In die cjmt ot ther mal-insulation wed, this aiUptabibu makv- p.oUlv the formation of a fiU-r nsa*-, with a ftf dvad air Sjtarvs. Jo the ease o! air fklte r *o>1, a sU'tctnrc with adequate strength having an cmokKJ sutfuci for the application of ihc dostc*u1ii:ig adhe-ive, lo tr-istance to the passage of air. and high-beat rsUtat-v i n:*dt> possible. 7 be proj'eftic* of mcombtr-nliilti y ard dura* biht> ate hire apam o! gtea: artvjiiijg,- <S> Products *nd Application* As a general statement eojiecrimig ihc applicability of Fsbetglas. if may Ik said that i1ti< \*'r.jtile ma'crial can W ., U Utete difft '* w<1 fulfills th. Fro, 4,--\Ltjt): plain Maple filter a gathered on ckt forma; tube; (righli: Vy*.twii staple yam reinfe-w.' with continuous filament jam. . trial uujtlatlw. rafety. cndurii , Jigbukess in tc; The electrics! industry is tire ebtel user of FibtrgUs f .$ BudJ ma'. j^**o storage batt its textile form, ft U uwd vidvly as tapes, cloths, braid'* F * ^e by kptD, ^Jeoriags. *d lying .oosw-Sor .the .kunlaiicM of elmd-j plates. They tooson. generators, JivaAcrrcrt*. and vtbtf t*V*' ** | operatingand dirtributtng e^nipmen(. because reiati'* h ! thin laym of gbn tape "ill inflate r^vlland bc-^un i* ( ^ cmr^iycdsa tl /v ^Htgoodei ^ at Products T temarkaUe roi'tincv to heat willalfot rr.oioo lo oi"--<" diffusing rrwdit ar esaeir irghec fores ih^tt akcrr&fc mc'<< t tion naicriaf are ustJ, rilxrglas oHcr, the advantax'' ** >sinn right and space farinps, higher operating effievn-' i_ fo the field c and l<>ur juipT.cnt maininance costs whin u-vd s - b* to rgaw.* suitable nmiib ar.dirnprcgnjircs and in actrda,ot*-' *v *' i t>>ond tnjiwertnj tt'-hui^ues. " **niU*r nuisarn Itt tlec chemical tvld. falrfics arc Usug "hJ j` 1 cht:mCal filtration cloths, especially uikr <onditi.*<cr * ^ vofvirt; corriv-tve houid or ga-cs at high tuflf>cf'af|-,,, , aad (2) an<*rte bag* lor ckctroplatiitg procc*-cs. Mi-*' [ Saaei> uidj.:r!a) uw> ol FiiK'iglas lahfu rauge f'om <' mat? v ion. ra><*i.vg adfn surface . ,u'riy |0w ft*. lagging and lacings for in>uliuon boKi io ".** fc; b<* sene Or oil lamps and stout. propen, rJ^cvug air. Fibers!*? lhcraa!'imtj)3ik>n "ool J5 prcKO-cd i many forms to make it mor adaptable lot pjtlicubr o~* j \*ot. N> IV S*^ sfiecei V Fibcrtfat: Some Properties and .Yr Applications <3 ptt4'jv degree of fleuSilit.y or rgidi*7, et'caal fora. and condition can all be varied to *j< it? application, jlujt the maHri*! is prepared for ham? sad industrial purpascs not only in the (era of a fleecy white wool of )* | lb. P?r cu_ ft. density, but aJo to fieaibk.to-rigid breta. metal-mesh and s?tre blankets. blocks.,and beards <1 -tftdcttymttvd specifications. which are used for la- all types of industrial equipment. cb ail tempera* srr ranges frtm subzero to 1200T.. according lo the pe&rl. Standard sizes en4 ibkksmcs at sersioaal pipe Eolation art abo fabricated from the original basic theesufia-ukting wort fiber. gradually finding their way into industry and others uitj soon appear. Some of the sew developments are laiprevemexts on old products, and la general these depend on the impotUnt FibergbspropertyfadaptalrilHytoorderly,predeter, raffled arrangement. St#h a dovricpoMS* is the tonforced staple sliver. The incorporation of a ewatisuous strand la the staple sliver daring forming or twisting pre* vents further drafting and yields a produce nhkh k ao effective filler for electrical cables. Other ocw developments have grown <**t of newer method* of processing and application which take fuller advantage of certain desirable properties. r' \ Z `Pro, b.--FibergUs sktvmgs, tyae* cords, electrical * krektiot UPs and doth*. and chemical filtration detin. These isustraie only a few of the end prwfaeta bailt ' from Ibc original textile fibers by a succession of twisting, ftyfeg, secarbtg, and braiding proecsoa. A -* fa Uwsc different products, Fibergks thermal4asnlatiof ad fulfill* the necessary requirements for a good Industrial bsulatios, namely. k>w thermal coaducihity. fire tafy, coduring resistance to vibrations and settling, kghtneM in weight. cleanliness, and durability. Oofidcd mat Gt>cr finds its greatest use as retainer mats fc storage baitcries, Tbcsc mats greatly extend battery fife by keeping active material in place on tb battefy S^aIo. They can serve this purpose because tit?. g!a employed in them ti resistant to attackby the battery arid has good ctccln'csl'iosuUtien d4aerao*rirt. Ibwakti vat products have been used leas eeteBsircfy as a light* * 4uft| mtdtuoa, asan thorgask facing material, and as a eating for underground pipes to combat electrolytic corroNrm. tn tb? fkld of atr conditioning, the adaptability nf Fiber* tiu t, organised arraagemcai Is again recognised. The fifta units for removing dirt, list, soot, plant polfcns, and uaiUr nuisance dusU from the air are bufli up of a series filter mats whieh differ io the sizes erf fibers used fa their *'*nlntcttoe. The Individual fibersare ccoted wh h a dusttiUAg adhesive. This orderly arraegemeol allows a Wge surface contact m a limited space and filters rela*rn}f irjM teWsiance to the ptraagt of sir. Tftese osrpiopettics mean, on interratwin. a high capacity for `kaj air. IV. Ne Future Application* <Jfe<tivc Fihergks pioducu and applications are '1*3) Fig. 6.---Some products derived fros fcaulatioc wool and a roll of hooded rant fibe frequently used as a being material. Aainteresttognewapplicatkffl ofFSiergUs is ia the field of hydroponics, where effective use k nude t its hereto fore relatively obscure property of controlled capillarity, Glass-tape orickrag in combination with peat boss feeds chemical solutions to the jdaat roots at a fired rate. Fihergta* therm*2-insulation wool k the raw material used in lb* production of a new strong, rigid figfriwrigfcC insulation board by a newly developed process that com* bir.es pressure and a carefully controlled heating cycle (o increase the density of the material without loss of resili. ncy. Thit board, used largely as a rcusfunatios insula tion and surface fi&tsh, releases for other purposes Urge quantities of aluminum formerly used as a facing mate* rialover Fiberfilaslasuktsoo wort, .Dm>*rlobed to replace cork for low.irrapemture insula tion, FiiKrtlas AE board, a rigid bat of Insulatisu wool csidovd io vphalt. H being widely used is domestic food storage lockers and In other large-scale refrigeration units. In tl<c fleld of lucdseinc. Fibcrgfas is undergoing thorougb iftvtstigJtion as a surgical suture1 and as s tracer yam in surgical spouges.* 2a addition. FfocrgUs tape U !>eing used fc filter o|c*ad plasma in atmy 6rtd kits.* Doth bonded mat of the type used is bsuaics and chemical filter cloih have been used quite suvce*ful!y In 1 Roy P. Scbrt* and f'hilip S. ^fountioy) "Fiberglas Sa:ure MsSerts}," Jent. Surgery. S6 13} 019-21 (19431 1 Ed*rd F. Lci-on. "RayaH* Gau s Factor of Safe?'' m Surreal Oiwrations.1' SitU. A met. Coil. Su'ge^m. 27 If] 39~JtiiI9). "NcH-Typ* I'Jasma Fshcr Aid in Vre'ention'rt Fa<al Wound Shock.'* S"u'giVflf Butineis. June. 64 Suilelin oj The American Ceramic Society--Emsi laboratories as filtering pad* in BuchrwT frtoaels wbcs the solution* being filtered weredestnietiee toordinary fuptn, Mag? den*?live applications of Fiberglas have fee** developed in the past, ibis devdopmest undoubtedly iJ> prtcttd at some more appropriate future time. Vari ety catered damasks, broades.satms. taffetas, aud acts bare been well established, aod products made from tbee teefade overdiapes, glass . cvmi.ias, ifeowes euromy bedspreads, tabledoths, and lamp shades. V. Role of Fibers far the War creftcr Csed at as effective replacement maieriaf for *erfc. Booferroar asbestos. aluminum, and laic*. Fihcrglas is becoming important as s strategic material the war program. Electrical manufacturers and design csgi&crri have sieved savings in bekh space sad **ight la new electrical equipment t trough the use of Frbergla* eleetrieaf tapes and cloths. Fiberglas U taking the place of cork sa certain types of tow-temperature snsulatlaa. It also eombvMdVstb mica Vo lb* mawriaetunt rf gremd tnsoVa* itoa for electrical equipment, thereby reducra* consider ably b Quantity of mien required. Kniow Umuiosb* Q1rt CHK6 CMNlAlWII N'rrac. Oaw MODELING SHEET GLASS IN A POrT.ERV'lCILN* 3v Dotty.M.Ekxst ABSTRACT A method is described for obtaining rebel pattern to sheet glass while bendieg it into decorative aod unable forms. The fact that sheets of glass may be best is a eeramfc are worked out m high relief. This expiate* (he pebbled mold is a pottery kiln has bees discovered hi tbeCeamae texture of tome of the piece. The porosity of the biscuit Laboratory of the University of Cincinnati When the cause* the fcibs trash to dry with a pebbled surface. glass is cooled. It has an appearance quite different from The type of modeling aho affects the success of the ini* the crisp perfection of glass bent a the smooth metal peeasioB. The heavy creeping sun of heated glass has a molds used commercially. It Is more like old haed-rollcil tendency to slide over the ercrieea. Definition is given gtags. by a calculated change In fens that checks this viscous Thelends**? tsf thehealed ghua.soilbendstolb* *ape fiow an issuoA, ^ving an accent where ttis needed; other. of the mold, to pkfc up impressions of each minute msed *>w4*e the pattern may show as a lot of coeasiogtaa bumps particle may be developed Into impressions of definite, calculated reliefpattens. The process Is simple. &folds are made of day. the dagn is modeled thereon, aad they are bbcuHcd. A wash of clay and flint (S3 aod 75%, respectively}, plus a bale gtuo tragacanth. is applied to the mold to parent the glass from adhering to it. A clean sheet of glass cur ro 6t the outer contour of tl* mold t* placed on it. aod it b. ready to he pot Into the kilo. The temperature is broegbt upslowly to a point just sufficient to cause the heated glass to move down. It sinks as a heavy film, finding the vrv us levels of the modeled surface. The temperature required varies with different glass compositions. Experimentation is necessary to find the temperature best suited to the type of glass being used. It win probably be around < 012, or J3*F. Proper regulation of temperature h required because heat that is too high that U mate?steed too long w\H o,VBe tie face to slip or todevitrify, The kiln must be cooled slowly to anneal the glass, as rapid cooling to rigidity will create strain. The upper surface ot the melded flaa* will be smooth aod trill need no further attention, The onda surface, however, wifi require cleaning Inasmuch as *ne of the kfla wash may be picked up, A mild abrasive and a wet brush may be used, hut neither should be hard enough to scratch. A silicon carbide stick may be needed tv smooth the edge if the firing has been too drastic. Tofind thefull e*ient el tbe ops and <fons fbat (hr glass will titkc. a coarse clay has been used for the forms, because the chauceof cracking o? breaking ii lessened if designs la the glass. The exact reproduction of designs primd mto a mold is the traditional manner should not be re* pected or attempted. The outer contour should be costrolled by designing the mold so that a support for the edges of the sheet of ghm is provided or wwp*g may occur H the ht of the late is uneven. Small holes may be drilled is the deep crevice* If the modeling is i quite high relief to expel any trapped air that may cause a Irubble in a reverse direction, A surprising amount of modeling i* possiute. A variety vl different impressions may be made from the same mold by using different forOgu aod domestic glass compositions. Single- aad double-strength window glass is used for small molds; crystal and plate glass are used for large mold*. All typo of glass b*nd satisfactorily; the temperature re quireef.ofcourse, varies. Otho* experiments have consuted of stacking layers at glass together. Cbaa. eat in triangles, squares, etc., and placed in pattern oa fiat sheet glass laid oc a mold fuse to gether as the glass bends to the meld. When vsrious- tolored glasses are combined, chipping and cr&ring occur if the fonmtku arc not "S3*rapa(belle." Design possibilities are limited, owing to glass-cutting difficulties!. Overglare ceramic colors stored on a fiat sheet in the same manner as glass enamels also bend with the glass. Ceramic molds are durable m a commercial, moving, circular kiln. Glass bends sati'lai-torily m an undecorated mold, bnt few pcrfrcr impressions are obtained from the decorated molds. A pottery kiln gim b beifcr texture to tb* glass. , The materials needed for the modeled herd glau arc jo- Presented at the Forty-Fourth Annual Meettog, The American Ceramic Society, Cincinnati. Ohio, April 21. 1942 (Art Divnion), Received September 15. J&42. e*|>ensive, and, aside from a potury ki!n. little cquiprrM'nr is required, Rt?At Hom 3 Lorsi-tVD.Ono vs. in. Ko s COHVER: < rtescal cun l tfjodes-sof pR ( corred from u ! thirty year*. f In 1910 and ! Ofrie were pa pattual gas to ' eouctry. Gbi j producer gas c ; loeeorieariSc i i* operate. i Abou, 19. rfie writer was mriaal b*b ", jhieGai Com i WestVtrt with e( t idcMdmgest rfeskfag Eoa &9 Sms, l S& wire *3*at reBimril the . <; iBtfca? *dGBc oaturml ------- leak After the or. y*~ was obu 'ifHi / ,waspossible to : 1 thse atost of 'Vk Piping and b v>bg whh produ< Up to the i ...jJaM* ow the qettingofSu. -jss Onrfirst glass j This *S~Sf<hy main pr figvrauve. lu. iasuliatio most Of t) la Uter iesu j--gesdqgujyos, for tti, ^Z.*Mced down depcodec f^sreaoax ^ ^ ( l - ***** the 1 *. teverriag m. * r.*- _ S><>crgTrs . * Wea? M.Abwc. <9bw23, <IW3)