bluuebunny/crossref_metadata_2025 huggingface dataset:
ORGANIC AGENTS AS AIDS TO THE ADHESION AND SUSPENSION OF GLAZES1
Authors: Foster E. S.
Published: June 2006

One phase of glaze preparation and application that has received very little description deals with the use of organic adhesive and suspensive agents. This paper describes the kinds, sources, and uses of the principal organic agents. In addition, shop practice with reference to terra cotta glazes is described. To supplement these descriptions curves are given showing the comparative effects of organic agents on the bonding strengths of a ball clay‐silica mixture.
THE MANUFACTURE OF FUSED BIFOCAL SPECTACLE LENSES1
Authors: Montgomery Robert J.
Published: June 2006

I. The process of making fused bifocal spectacle lenses is based on patents taken out about 1906. Such lenses are made by fusing a crown glass with an index of refraction of 1.5230 with a lead glass having indexes of refraction of 1.616, 1.66, and 1.69. 11. Problems in making satisfactory glass involved thermal expansion, surface crystallization, surface bubbles, and the softening temperatures of the glasses. The effect of composition of the glass in curing these defects is discussed and satisfactory compositions are given. Testing methods for control are given. III. A later development is the so‐called colorless fused bifocal in which a barium glass replaces the lead glass of the normal lens. The use of barium glass introduces new problems, especially the quality of the glass and the tarnishing of the surface. The relative softening temperatures of the barium and crown glass as well as the thermal expansion had to be controlled.
RATE OF DRYING OF A PLASTIC PORCELAIN MASS DUE TO REDUCED PRESSURE AND HEAT1
Authors: Navias Louis
Published: June 2006

Experiments in drying plastic porcelain masses are performed using reduced pressures of 0.7, 5, 15, and 36 cm., with surrounding temperatures of 23, 50, and 65°C. Plotting the logarithm of the loss of weight against the logarithm of time, straight‐line relationships are found to exist for the drying rate. With the lowest pressure a single slope is found, whereas with the three higher pressures there are two slopes to each curve. The lowering of the temperature of the whole mass with lowering in pressure is shown. Effect of shape of specimen and humidity of air on rate of drying is discussed.
THE PREDICTION OF SERVICE VALUE FROM LABORATORY TEST DATA1
Authors: Westman A. E. R.
Published: June 2006

Accurate prediction of service value is a prerequisite to the devising of methods of control, development, and specification based on laboratory test data. The precision conditions which must be met before such prediction is possible are given in the paper and the difficulties usually encountered in trying to meet these conditions in ceramic work are shown by examples chosen from the field of refractories.
USE OF PULVERIZED COAL AS A FUEL FOR PERIODIC KILNS1
Authors: Watson D. J.
Published: June 2006

A research problem on the control of the temperature, using pulverized coal as a fuel for intermittent kilns. The paper consists of a description of the operation and design of a fire box with a hot‐spot combustion chamber for the ignition of the fuel during the water‐smoking period, and first part of the oxidation period.
STABILITY AND PROGRESS OF THE PUBLIC UTILITY FUEL SERVICE1
Authors: Gates E. L.
Published: June 2006

Because ceramic products require accurate control in all heating operations, natural gas has acquired a high rating as a fuel, but because of difficulties encountered such as exhaustion of supply, distant markets, etc., producer gas is more popular. City gas is available in all urban localities and therefore broadens the selection of location for any industry. The question of price of the city gas as compared with natural gas is dealt with and it is pointed out that the increase in recovery of by‐products and efficiency of manufacture, together with a steady decline of price of the utility fuel service since 1923, tends to lessen the difference in price between city and natural gas. Examples are cited where city gas is used for enamel smelting and brick firing successfully.
A SANDBLAST ABRASION TEST FOR GLAZES1
Authors: Schramm Edward
Published: June 2006

A method is described for determining the abrasive hardness of glazes by means of a sandblast apparatus. Consistent results are obtained and data are given showing the relative hardness of several types of glaze.
A COKE‐FIRED GAS PRODUCER FOR THE CERAMIC INDUSTRY1
Authors: Barrety H. C.
Published: June 2006

The initial installation of a coke‐fired gas producer for manufacturing gas for firing silica brick in the United States is described in detail. The advantages of cold, clean gas over dirty gas are pointed out with clarity. The features of the automatic operation are set forth, showing that a better grade of constant volume and pressure gas can be produced. Operating data of a plant on million cubic‐foot basis gives the power, coke, and water consumption.
A NEW TYPE HIGH TEMPERATURE FUSION FURNACE1
Authors: Shaw J. B. , Bair G. J.
Published: June 2006

The limitations of carbon, gas, and electric furnaces for high‐temperature fusion are discussed. The new oxyacetylene furnace controls the atmosphere in contact with the test cones, protects furnace parts, and insures uniform conditions throughout the furnace.
PRESENT PRACTICE IN WHITEWARE PERIODIC KILN DESIGN1
Authors: Mills R. G.
Published: June 2006

Tables of whiteware kiln dimensions and design ratios are presented. Distribution charts are included which show the present tendency in kiln size and kiln design factors. Attention is called to the wide variations found in some of the design factors and to the rather narrow limits within which others fall.
A DEFORMATION STUDY OF COBALT OXIDEIRON OXIDE‐SILICA MIXTURES1
Authors: Shepherd John F.
Published: June 2006

Deformation eutectic fusions are reported for 46%Co3O4‐54%Fe2O3 and 36%Co3O4‐42%Fe2O3‐22%SiO2. Either of these eutectics could be substituted for cobalt as an enamel ground coat.
LINOLEUM BLOCK PRINTED POTTERY1
Authors: Loshinsky Sadie
Published: June 2006

A study of three methods for applying color to pottery with linoleum designs is presented. The procedure is practical for studio potters and small factories rather than for quantity production.
WET‐PROCESS LEADLESS CAST‐IRON ENAMELS1
Authors: Andrews A. I. , Commons C. H.
Published: June 2006

Several promising compositions have been developed in the laboratory in an extensive investigation for the development of satisfactory leadless wet‐process cast‐iron enamels. Each series investigated is described. It is concluded that such an enamel is feasible as several fair enamels and one good one were developed during the investigation. Best results were obtained when the enamels were washed and although this is impractical in plant practice it is hoped that an insoluble frit may be obtained thus eliminating the necessity for washing in order to obtain the required gloss.
THE CAPILLARY SUCTION OF SOME CERAMIC MATERIALS1
Authors: Westman A. E. R.
Published: June 2006

The forces which act when clay is mixed with water and when water is removed from wet clay by evaporation have received little study. For this reason, very little definite information regarding the internal mechanism of the drying of clayware is available. In this paper, the writer reviews the experiments and theories of Pukall, Terzaghi, Dixon, etc., lists some of the forces which may act when ware is drying, and defines an important force which he calls “capillary suction.” A simple experiment is described, by means of which this force can be readily demonstrated. The development and final form of an apparatus for measuring the capillary suction of ceramic materials is described and data obtained from measurements on a ball clay, a kaolin, flint, feldspar and mixtures of these substances are reported. Capillary suction decreases rapidly with increase in the flint and feldspar of a ceramic body. By utilizing the capillary suction produced by evaporation of water from a clay surface, water at atmospheric pressure has been made to enter a steel bomb in which the gas pressure was maintained at 200 lbs. per square inch.
THE EFFECT OF MAGNESIA ON THE DEVITRIFICATION OF A SODA‐LIME‐SILICA GLASS1
Authors: Morey George W.
Published: June 2006

The effect of magnesia on the devitrifimtion of a certain soda‐lime‐silica glass has been ascertained. The initial glass had a composition 1.15Na2O.0.84CaO.6SiO2, and tridymite separated as primary phase. On substitution of MgO for CaO, tridymite remained primary phase, and the melting point was lowered, but the curve shows double inflection. Addition of 2% of MgO lowered the melting point almost 200°, with the glass passing from the field of tridymite to that of Na2O.3CaO.6SiO2, but with more than 3%, MgO diopside became the primary phase, and the melting point rapidly increased.
THE EFFECT OF ALUMINA ON THE DEVITRIFICATION OF A SODA‐LIME‐SILICA GLASS1
Authors: Morey George W.
Published: June 2006

The effect of Al2O3 the devitrification temperature of a soda‐lime‐silica glass approximately of the composition Na2O.CaO.6SiO2 has been studied in two series of experiments. In one of these CaO was partially replaced by Al2O3 until the final glass had the composition of the mineral albite, Na2O.Al2O3.6SiO2; and in this series of experiments the melting point of the glass was first lowered, until the glass passed from the tridymite into the Na2O.3CaO.6SiO2 field; then rose slightly to a maximum, fell until the glass entered the field of CaO.SiO2, and then rose rapidly until the field of albite was reached. Glasses near albite in composition are practically impossible to crystalliie in the dry way. In the second series of experiments, Al2O3 was added to the same glass, and it was found that the fields of tridymite and Na2O.3CaO.6SiO2 were quickly passed through, with a smaller lowering of melting point than in the preceding series, after which the melting point rapidly increased, with CaO.SiO2 as primary phase. It is shown that no generalizations can be made as to the effect of alumina on the devitrification of soda‐lime glass. The problem is one of the freezing‐point relations in a four‐component system, and in the absence of definite knowledge of the liquidus temperatures and corresponding stability regions in that four‐component system general statements would probably be misleading. In addition, the devitrification of some five‐component soda‐lime glasses containing both Al2O3 and MgO is discussed.
THE CASTING OF CLAY WARE—A RÉSUMÉ*
Authors: Hall P. P.
Published: June 2006

Considerable difficulty has been encountered in developing methods suitable for determining the properties of a casting slip that in turn define the casting quality of the slip. A survey of the literature is made, especially that dealing with the colloidal phenomena of clay suspensions, which might be of assistance in solving some of the problems encountered in the use of the casting process.

The term, casting quality of slip, is detined and the factors which influence this property are considered in detail. Control methods proposed by various investigators are discussed critically. A new method of slip control is suggested. The sources and remedies of some troubles encountered in the casting process are discussed.
A DEVELOPMENT IN SPRAYING DEVICES1
Authors: Grady R. F.
Published: June 2006

A spraying machine is described which not only permits of accurate control, but possesses sufficient flexibility to produce all types of mottles.
VAPOR GLAZING AND COLOR FLASHING OF PRE‐CAMBRIAN SHALES1
Authors: Longenecker Hilton L.
Published: June 2006

The demand for colors in brick was first met by the manufacturers of red face brick by fire‐flashing their normally red firing material, producing a range of brown and brownish red colors. Later they used vapor glazing with zinc and color flashing with coal tar. The red face brick color range includes green, mustard, purple, and glossy black. This paper describes the materials, methods, and results obtained at the Sea‐board Shale Brick and Tile Company plant at Monroe, N. C., and was checked at other plants in the same district.
ALTERING THE PROPERTIES OF HEAVY CLAYS BY THE USE OF ELECTROLYTES1
Authors: Husain Tajamul
Published: June 2006

Some heavy clays otherwise adaptable to industrial use have poor working properties. The possibility of altering these properties beneficially, by the addition of electrolytes to the clays, was investigated. The effects of acids and bases, or those salts which when hydrolyzed, reacted as acids or bases, gave the most promise. Physical properties were determined in the laboratory, on three clays in the green and fired states, without electrolytes and with hydrochloric acid, tannic acid, sodium carbonate, and calcium chloride. Some plant tests were also made, particularly on drying. It was found that the addition of electrolytes improved the properties of some clays, the electrolyte and amount required being individual with each clay.
THE RELATION OF BRINELL HARDNESS AND TRANSVERSE STRENGTH TO THE COMPRESSIVE STRENGTH OF BUILDING BRICK1
Authors: McBurney J. W.
Published: June 2006

This paper reports the results of Brinell hardness determinations on twenty‐five makes of brick together with their transverse and flat compressive strengths. These data indicate that though there is somewhat better correlation between Brinell numbers and flat compressive strength than exists between transverse strength and flat compressive strength, yet the relation is not sufficiently exact to permit the accurate estimation of flat compressive strength from a measured Brinell number.
AIR CONDITIONING IN CERAMICS1
Authors: Matzen H. B. , Parmelee C. E.
Published: June 2006

This paper outlines the general factors considered in an air‐conditioning problem. The present type of applications in the ceramic industry include (1) complete drying of ware, (2) conditioning of material and formed pieces, (3) humidifying and dehumidifying of manufacturing departments, (4) air washing, (5) cooling for comfort. Illustrations showing details of some of these cases are included. The present progress indicates the general line of future development of air conditioning in the manufacture of ceramic products.
A RAPID‐FIRE TUNNEL KILN DESIGNED FOR SMALL PRODUCTION1
Authors: Donnenwirth A. L.
Published: June 2006

A miniature tunnel kiln was designed to fire spark plug porcelain to cone 17. It is capable of producing about 10,000 porcelains daily. The total firing time is only slightly more than two hours. The kiln, its operation and efficiency is detailed.
TRANSVERSE STRENGTH OF BALL CLAY‐SAND AND BALL CLAY‐FLINT MIXTURES1
Authors: Collin L. P.
Published: June 2006

Tests of dry transverse strength on 30 ball clays using mixtures of 50% ball clay + 50% flint, and 50% ball clay + 50% standard silica sand, which demonstrate the method adopted as a tentative standard and which specify the use of silica sand as the nonplastic, are unsatisfactory for determining the dry transverse strength of highly plastic clays. More consistent results were obtained with flint as the nonplastic.
OBSERVATIONS OF CAUSES FOR INCONSISTENT RESULTS IN COMMERCIAL FINENESS TESTS OF PORCELAIN ENAMELS1
Authors: Wolfram H. G.
Published: June 2006

Results are given of commercial tests showing inconsistencies in results obtained. Investigation proved these differences to be due to careless manipulation, clogging of screen openings in the original cloth as manufactured, and distortion of the mesh in fastening the cloth to the frame.
METHODS FOR THE DETERMINATION OF THE FIRING RANGE OF VITREOUS ENAMELS USED IN WET‐PROCESS ENAMELING1
Authors: Kinzie C. J.
Published: June 2006

Several methods for making firing range studies in case of wet‐process enamels are described. The methods used in producing enamel deposits of predetermined weights are given. The use of these methods has shown that enamels used in wet‐process enameling of metal vary widely in action under various conditions of heat and a general discussion of the subject is included.
CONSTRUCTION OF WATER‐TIGHT BRICK MASONRY1
Authors: Anderegg F. O.
Published: June 2006

About 300 panels have been erected to determine the effect of some of the various factors of different brick, mortars, workmanship. and design in causing leaky brick walls. The brick varied in absorption from 0.6 to over 12% of their weight when placed flat side down in 1/8 inch water for ten minutes. The mortars included both lean and the richest mixes of lime and Portland cement in varying proportions and of a large number of masonry cements. Most of the panels one brick in thickness leaked in half an hour on being sprayed with a hose. A very few mortars were found that were quite tight. Those panels with an air space between the front and the backing allowed no water to pass clear through the wall. Many panels have been broken in flexure with very interesting and important results. Other panels have been built to test out interior ventilation of walls, and many other points have been studied.
THE EFFECT OF DIFFERENT FLUXING OXIDES ON THE CONSTITUTION OF PORCELAIN1
Authors: Fessler A. H. , Navratibl Hans
Published: June 2006

This article deals in a general way with the constitution of siliceous porcelain. The influence of the different fluxing oxides on the formation of the glass phase is indicated by solubility and specific gravity determinations as well as by microphotographs.
RECOVERY OF PILLARS IN CLAY MINING1
Authors: Augsrurcer Clyde
Published: June 2006

After a brief review of the history of former operations and the general layout of a mine, the methods used in National Mine No. 21 at East Canton, Ohio, are described in detail. The plan of the mine, panel layout, and the removal of an individual pillar are described with illustrations showing how more than 80° of the clay is recovered. Conditions and results in a number of other mines are given with illustrations of the methods. The relation of a high percentage of extraction to costs and safety is discussed.
METHOD OF MEASURING STRAINS BETWEEN GLAZES AND CERAMIC BODIES1
Authors: Schurbcht H. G. , Pole G. R.
Published: June 2006

A new test was developed for comparing the strains existing between different glazes or other ceramic finishes and the bodies to which they are applied. By its use these strains may be so adjusted that the finishes will be in suflicient compression to prevent crazing from subsequent expansion of the body without causing initial shivering. The new test is particularly valuable because the measuremen & are made on combinations of glaze and body prepared and treated almost exactly like those intended for regular use and because of the simplicity and cheapness of the apparatus required. A modification of the test provides a comparison of the moisture expansions of different bodies.
BERYLLIUM GLASS, II POTASSIUM‐BERYLLIUM SERIES1
Authors: Lai Chi Fano , Silverman Alexander
Published: June 2006

This paper includes a triaxial diagram for the potash series, containing two good glass areas in contrast with a single area in the soda series.3 One area is in the region of low beryllia and high silica; the other in the region of high beryllia and low silica. The latter contains the better glasses. Areas are also shown in which the tendency to increase silica produces opalescence while that toward an increase of beryllis promotes divitrification. Great difficulty has been experienced in obtaining pure beryllium oxide. Material that was supposedly pure contained as much as 20° of moisture. Difficulty has been encountered also through such impurities as the oxides of iron and manganese. One sample of supposedly C.P. beryllium oxide contained over 90° alumina. Optical data are not yet available. As was the case with the sodium beryllium silicates. so here again the announcement is the first of the potassium‐beryllium glasses, t o the best knowledge of the authors.
PRODUCTION OF A SALT GLAZE BY THE APPLICATION OF A SLIP TO THE WARE1
Authors: Everhart J. Otis
Published: June 2006

Glazed surfaces can be produced on the face of ware mode from practically any clay or shale having maturing temperature of cone 1 or more by coating the face of the ware with a slip containing sodium chloride. Various concentrations of salt in the slip have been used. Lower concentrations do not produce glazes but develop interesting surface and color effects. Metallic oxides may be used to produce variation in color of the glaze. This method shows promise as a means of securing salt glazes in kilns which have heretofore been considered impractical for salt‐glazing purposes, although it has been developed only in the lahoratory stage at the present time. Sodium carbonate has also been used successfully.
SOME SIMULATIVE SERVICE TESTS FOR GLAZED BUILDING MATERIALS1
Authors: Evbrhart J. Otis
Published: June 2006

Several methods of freezing and thawing tests have been compared with each other and with the standard autoclave test with regard to type and rate of failure. Data indicate that the autoclave test alone is not sufficient to predict behavior of glazed ware in service, especially in the more severe climates.

Glazes follow very definite laws as to rate of failure under conditions of freezing and thawing. Curves have been developed which indicate the nature of these laws very clearly. Considerable data have also been obtained on the effect of freezing on the porosity of brick and on the nature of failure of glazes.
THE DEVELOPMENT OF ACID‐RESISTING WHITE SHEET STEEL ENAMELS1
Authors: Andrews A. I.
Published: June 2006

Many of the commercial sheet steel enamels are readily attacked by such weak acid solutions as fruit juices and are stained by milk and by some city waters.

This paper gives the development of a number of acid‐resisting enamels. It shows that acid resistance is the result of the right combinations of raw materials rather than the presence or absence of any particular constituent. Acid resistance is not affected by fineness of grinding or by the smelting conditions if the enamel is properly smelted. Mill additions of clay reduce the acid resistance but opacifiers added in this manner have no effect. Temperature and time of firing may or may not affect the acid resistance depending on the composition of the enamel.
THERMAL EXPANSION OF SILICA BRICK AND MORTARS1
Authors: Coler Sandford S.
Published: June 2006

Thermal expansion from 20 to 950°C and physical data of silica brick from various producing districts in the United States and Europe are presented. The variations in thermal expansion of brick from various parts of kilns are given for plants in the United States.

The magnitude of variation of the thermal expansion of silica brick is quite small, the expansion ranging between 1.15% and 1.30% at the highest point of expansion. The expansion of the silica mortars varied between 1.30 to 1.52% depending upon variations in clay, quartzite, and bats.

The variations in thermal expansion of silica mortars from various producing plants are also shown. Data on the effect of size of grain, clay content, and P.C.E. on the thermal expansion of mortars are given. An extensive bibliography on thermal expansion of silica brick appears with the paper.
A SHOP METHOD FOR COMPARING SUBSIEVE PARTICLE DISTRIBUTION IN NONPLASTICS1
Authors: Hunt M. H.
Published: June 2006

A sedimentation for determining subsieve particle distribution is described. The Curves obtained apparatus is simple and efficient enough to be used in shop practice. on feldspars and flints as well as other ceramic materials are shown.
AN UNUSUAL KILN SCUM1
Authors: Henderson H. B.
Published: June 2006

A heavy, white, fuzzy coating on brick developed in the firing. The coating consisted entirely of silica, produced from the reduction of silica and vaporized as silicon and reoxidized.
THE EFFECT OF ADDITIONS OF CaO AND MgO ON ENAMEL GLASSES1
Authors: Parmelee C. W. , Shaw D. T. H.
Published: June 2006

An attempt to determine quantitatively the effects of various additions of CaO and MgO to a simple soda‐lead‐silica glass upon the physical properties of the glass and the working properties of the Same when used as an enamel was made in this investigation. The tests on glass consisted of thermal expansion, softening range, compressive strength, modulus of elasticity, solubility in acid and alkali, and index of refraction.
DIMENSIONAL CHANGES CAUSED IN GLASS BY HEATING CYCLES1
Authors: Tool A. Q. , Lloyd D. B. , Merritt G. E.
Published: June 2006

In obtaining expansivity curves for a medium flint glass, samples of the glass were tested which had previously received one or another of several different heat treatments, and in these tests heating cycles were employed which made it possible to determine that the magnitude of the so‐called “permanent” changes in length are caused either by the annealing or the “disannealing” which may result from the heat treatment imposed on the glass by the heating cycle employed. Annealing decreases the length and specific volume, while disannealing increases them. It is shown that these effects are related to certain ice‐point shifts observed in thermometers, and to other effects sometimes observed in various types of glassware.
COLD CRUSHING STRENGTH OF FIRE BRICK1
Authors: Mitra Himansu K.
Published: June 2006

Data on cold crushing strength in three directions, viz., flat, edge, and endwise of six brands of fire brick are given. Transverse strength data of all these brands are also given. Porosities of all the brick used in these tests were determined by the air‐expansion method. The purpose of the investigation was to find whether it is possible to translate the values obtained for crushing strength of fire brick in one direction (flat) into values for the other directions (end and edge); to determine whether transverse strength data can similarly be transformed to crushing strength data and vice versa and whether porosity and crushing strength of fire brick are correlated. The data herein presented do not show the existence of any such simple mathematical relationship between the different properties of the brick.

A new capping material, a mixture of sand and molten sulphur, was used for the crushing tests, and was found to be more satisfactory than the other materials commonly used for the purpose.

It is recommended that in reporting crushing strength data of fire brick, the brick be tested on end.
DETERMINATION OF THE ALKALIS IN VITREOUS ENAMEL1
Authors: Schaal Robert B.
Published: June 2006

Sodium and potassium comprise from 5 to 25%, of the total composition of vitreous enamels. The other 75% is comprised of a wider variety of other elements than is found usually in materials which are analyzed for their alkali content. No less than twentyfive oxides are used commonly in enamel glass, and often fifteen of these are in a single enamel.

The task of removing all interfering elements from the alkalis is an analytical problem of more than ordinary difficulty. The process is necessarily long and tedious. It calls for the most exact attention to detail and the most careful manipulation.

This article tells of attempts to use the usual methods for determination of alkalis in vitreous enamel, and also the procedures found to be most useful and accurate for all classes of enamels.
PROGRESS IN THE ELIMINATION OF SAGGERS IN THE FIRING OF GLOST AND BISQUE GENERAL WARE AND GLOST WALL TILE1
Authors: Dressler Philip
Published: June 2006

During the past fourteen years the use of saggers has been largely eliminated in the sanitary ware industry by the use of cars equipped with permanent superstructures of slabs and posts in muffle tunnel kilns.

Methods are described by which saggers can be eliminated for firing general ware and wall tiles with correspondinn benefits.
SOME DATA ON THE WHITEWARE INDUSTRY OF WEST VIRGINIA1
Authors: Koehler W. A.
Published: June 2006

Most of the usual types of whiteware are manufactured in West Virginia by 24 different firms. Data are given on the kinds of body raw materials used, and their geographic sources; the materials used for glazes; lawn meshes used; number and kinds periodic bisque kilns and glost kilns; number of car tunnel bisque and glost kilns; horns kilns are on fire and the cones reached in each of the various types of whiteware.
THE KAOLIN MINERALS1
Authors: Ross Clarence S. , Kerr Paul F.
Published: June 2006

A report of an investigation of the clay minerals, nacrite, diekite, and kaolinite is presented in which the methods of study are explained. The optical and physical properties, chemical composition, and X‐ray studies of these kaolin minerals are discussed and the results of the study are outlined.
AN ELECTRIC SPALLING FURNACE1
Authors: Baumann Henry N.
Published: June 2006

An electric spalling furnace, heated by means of a graphite resistor and holding twelve test brick at a time, is part of the equipment for the routine testing of refractories in the Research Laboratory of The Carborundum Company at Niagara Falls, N. Y. It is more compact, more easily handled and repaired, more closely controlled, free of flame impingement, and much to be preferred to the fuel‐oil fired type of furnace which it replaced.
GEOLOGY OF THE FIRE CLAYS OF SOUTHERN SASKATCHEWAN1
Authors: Hutt G. M.
Published: June 2006

The fire clays belong to the Whitemud formation, which is of Lance (late Cretaceous) Age. The formation is usually represented by three zones: at the bottom a maximum 45 feet of partly kaolinized feldspathic sands, a thin carbonaceous zone in the middle, and at the top a maximum of 35 feet of plastic clays intercalated with fine sands and silts. Increase of the sands in coarseness eastward implies an eastern source of the sediments, possibly the pre‐Cambrian of northern Canada. The plastic clays are probably derived from the feldspathic sands and are due to a reworking of the sands and their kaolinization in Whitemud time. The strata are practically flat lying, with a regional eastward, and possibly northward, dip. The eastern clays, having fusions as high as cone 33, are more refractory than the western ones.
A QUICK METHOD OF DETERMINING THE WATER CONTENT OF CLAYS1
Authors: Deeds C. L.
Published: June 2006

The water content of clay is determined by taking a representative sample of the material, weighing out 2 kg. of it and adding 4 kg. of water. The sample is blunged quickly. A 250‐cc. flask is filled with the resulting slip and weighed. The amount of dry clay is determined from the relation:

D= (P−250)(G/G−1)

where D= weight of dry clay

P= weight of slip

G= specific gravity of dry clay.

From this the per cent water in the moist clay is readily computed.
A RAPID METHOD FOR THE ESTIMATION OF THE ALUMINA CONTENT OF DIASPORES AND HIGH ALUMINA CLAY1
Authors: Phelps Stuart M. , Hughes A. C.
Published: June 2006

A simple but rapid method is presented for the estimation of the alumina content of diaspores and high alumina clay. A comparison of results between chemical and physical analyses is given and even closer accuracy is promised with the use of an improved apparatus in process of construction.
ABSORPTION: ITS RELATION TO DURABILITY1
Authors: Whittemore O. J.
Published: June 2006

This paper shows instances of Iowa tile of variance from general classifications, of maximum absorption limits below which building tile are durable against freezing and thawing. Exception is taken to the A.S.T.M. Specification C34‐27 as to nomenclature and tests by which tile are classified.
THE RELATION OF METAL CLEANING TO PERFECT ENAMELING1
Authors: McIlhenny Edw. L.
Published: June 2006

The importance of the cleaning phase of the enameling process as related to production of uniformly good work is not always appreciated. Many troubles encountered commonly in porcelain enameling plants can be traced to the pickling department turning out unclean work. In order to control the cleaning properly there are a number of points which should he considered, such as type of lubricant used, production schedule, evidence of water hardness, and selection of proper type of cleaner.

A method has been suggested which applies to the water‐break test for determining the exhaustion point of the cleaning tank. Rinsing, packing or racking, and electrolytic cleaning are also of importance and merit consideration.
REFRACTORIES AND REFRACTORY CEMENTS FOR THE NONFERROUS FOUNDRY1
Authors: White Harold E.
Published: June 2006

Development in refractory linings for the various furnaces encountered in the nonferrous foundry industry is outlined, and figures given showing the present trend. These include open‐flame, crucible, and electric furnaces. The open‐flame furnaces formerly used firebrick linings, but silicon‐carbide and high alumina refractories are coming into use. The crucible furnace linings show a decided preference for silicon‐carbide refractories, while the electric furnaces are partial to the alumina and mullite bearing types.

Progress in the manufacture of refractory cements and their use in the various types of furnaces is discussed. Data are given which indicate that the use of the proper types of cements for maintaining furnace linings of similar composition is becoming more general.
OPACIFYING EFFECT OF SOME FLUORIDES IN ENAMEL MILL ADDITIONS1
Authors: Pearce R. Melville , King R. M.
Published: June 2006

This paper describes the results of a study of the effect of barium fluoride and zinc fluoride on enamels when added in the mill. These fluorides were used with high silica, high borax, high lead oxide, and high antimony oxide enamels. The effect of these fluorides upon opacity and the creation of such defects as crawling and crazing are shown by triaxial diagrams and photographs.
A SIMPLIFIED PRACTICE OF MIXING COLORED GLAZES1
Authors: Roehm V. J.
Published: June 2006

A simple method of mixing colored glazes is discussed, using one base glaze, by means of curves plotted from predetermined values for the percentage of solids and ounces per pint in both base glaze and colored stains.
A METHOD FOR DETERMINING THE LOSS OF WEIGHT OF CLAYS DURING FIRING1
Authors: Morgan W. R.
Published: June 2006

A simple apparatus has been devised for the comparison of the loss of weight of clays during firing by the direct weighing of the sample while suspended in the furnace. Preliminary results indicate that while the total loss of weight of the different clays varies considerably, the losses in any temperature range expressed in per cent of the total weight lost at 1800°F show a much closer relationship. The comparative ease of control will make it possible to examine the clays under a wide range of conditions.
THE THERMAL EXPANSION OF SOME REFRACTORY OXIDES1
Authors: Austin James Bliss
Published: June 2006

The thermal expansion of crystals of alpha‐alumina, magnesia, chromite, mullite, and zircon and of a mass of fused zirconia has been measured up to 1000°C. The results are exhibited in tables and in graphical form.
THE WEATHERING AND IRIDESCENCE OF SOME ANCIENT ROMAN GLASS FOUND IN CYPRUS1
Authors: Laubengayer A. W.
Published: June 2006

Samples of ancient Roman glass taken from burial vaults on the Island of Cyprus have been examined. Analysis shows the glass to be of the soda‐lime type characteristic that period. The heavy incrustation produced by weathering has been studied spectroscopically and microscopically and is shown to consist, for the most part, of hydrated silica, formed by the slow hydrolytic decomposition of the glass. The beautiful iridescence exhibited by the glass is due to the selective destructive interference of light the thin films of transparent incrustation on the surface of the glass.
X‐RAY AND MICROSCOPIC STUDIES OF SILICATE MELTS CONTAINING ZrO21
Authors: Barlett Helen Blair
Published: June 2006

Silicate melts containing ZrO2 were examined by means of the X‐ray and the microscope to establish the form of crystallization of the zirconium compounds under various conditions of temperature and composition. The effect of certain fluxes on these compounds was also determined.
X‐RAY DIFFRACTION EXAMINATION OF HIGH‐FIRED PORCELAIN1
Authors: Martin E. J. , Faulkner D. W. , Fessler A. H.
Published: June 2006

An X‐ray diffraction examination was made of high‐fired porcelain to determine if strains, differences in composition, or density of the crystalline phases could be detected. Both inherent and superimposed strains were studied. Although very small changes in the diffraction pattern of porcelain under superimposed strains have been recorded, not enough data have been obtained to state definitely whether inherent strains can be detected by this method. Details of X‐ray equipment and procedure are given.
PROGRESS OF FLUIDITY IN PORCELAIN BODIES1
Authors: Snyder R. A.
Published: June 2006

Firing characteristics of a group of thirteen clay‐flint‐feldspar porcelain bodies were studied. Firing shrinkage, porosity, and rate of deformation were determined on specimens of all bodies fired at a series of temperatures, thus observing the rate of vitrification and subsequent fluidity of each of the bodies in question. Cross‐breaking strength tests were made in order to ascertain the relation of composition and firing temperature to mechanical strength.
SILLIMANITE KILN REFRACTORIES MADE FROM AN ANDALUSITE BASE1
Authors: Riddle By Frank K. , Twells Robert
Published: June 2006

Some andalusite refractories are high in transverse strength. Bars 12 inches long, 2 inches wide, and 1/2 inch thick tested across an 11‐inch span supported a 45‐pound load with 13/32‐inch sag at cone 161/4 and a 1/2‐pound load at cone 34 down with 1/16‐inch sag. A standard 9‐inch brick tested under a load of 50 pounds per square inch at 1525°C showed no deformation. They are relatively constant in volume, are not affected by kiln gases, and tend to improve rather than to deteriorate under continued heating owing to the formation of an increased amount of mullite. Andalusite saggers used at cone 12 are estimated to have stood 180 cycles and are still in good condition. Saggers in continuous use at cone 161/4 have an estimated average age of 11/2 years and many are four years old. The andalusite lining of a periodic kiln being fired regularly at 3000 to 3200°F is still serviceable after 110 firings. Cars built of andalusite refractories have given five years of continuous service in tunnel kilns operating at cone 161/4, whereas cars built of fireclay refractories were unfit for use after three to four months. Side walls, damper boxes, expansion sleeves, and flame shields of Dressler tunnel kilns operating at cone 161/4 have proved satisfactory.
THERMAL EXPANSION OF SILICA MORTARS AFTER FIRING AT 950°, 1200°, and 1500°C1
Authors: Cole Sandford S. , Lynn Don C.
Published: June 2006

The thermal expansion between 20°C and 950°C of silica mortars after being fired at 950°, 1200°, and 1500°C was compared with the expansion of the materials before firing. The mortars showed marked difference in expansion behavior after being fired to 1500°C, indicating that there was developed a large amount of tridymite The thermal expansion of the fired samples is less than that of the unfired samples.
EXPANSION MEASUREMENTS OF SEVERAL GLASSES BY MEANS OF A SELF‐REGISTERING APPARATUS1
Authors: Cohn Willi M. , Scholes S. R.
Published: June 2006

Applying an apparatus which registers photographically, and using quartz glass as control material, the expansion behavior of several glasses upon heating to temperatures above the softening point was investigated. It is shown that, with the help of the arrangement developed, even slight variations in the expansion‐temperature curve, which might easily escape visual observation, can be detected. It is possible, by utilizing the results of these measurements, to regulate the annealing process of the glasses in the most useful manner.
EXPERIMENTS IN WEATHERING PLASTIC FIRE CLAYS1
Authors: Phelps Stuart M. , Dennet C. G.
Published: June 2006

A description is given of the test method and the data obtained for small‐scale weathering. Extensive data were also obtained on commercially weathered clays. The results obtained show that the changes produced by weathering cannot be readily detected by the usual test methods. Either the changes produced by weathering are over‐estimated, or the present test methods do not measure the properties involved.
THE IMPACT MODULUS OF GLASS1
Authors: PRESTON P. W.
Published: June 2006

This paper straightens out the physical homogeneity of the impact formula used by several American writers on this subject, shows the probable derivation of the formula, and proposes, by taking the square root of the formula, to reduce it to comprehensibility.
SELENIUM DIOXIDE AS A CONSTITUENT OF GLASSES1
Authors: Navias Lotjis , Gallup John
Published: June 2006

SeO2 is added as selenious acid (H2SeO3) and as sodium selenite (Na2SeO3 to the oxides Na2O, CaO, BaO, PbO, B203, and SiO2 to form glasses and crystalline melts containing apprcciable amounts of SeO2. The chemical analysis of glasses shows the vaporization of SeOn to be high during the melting stage. Most of these glasses are unstable in air or water. A relatively stable glass contained Na2O 33.4%, CaO 12.4%, B2O3 37.6%, SiO2 5.8%, SeO2 10.8%. Melting several compositions in a closed container yielded opaque or crystalline melts, whereas the same compositions melted in air with a partial volatilization of SeO2 gave clear glasses.
POWER COST ON AN ELECTRIC ENAMELING FURNACE1
Authors: Manson M. E.
Published: June 2006

With the furnace operating twelve hours per day, powcr consumption varied from 7 pounds of iron per kw.‐hr. for light loads to 13 pounds per kw.‐hr. for heavy loads. Operating in the daytime, this 215‐kw. furnace increased the average plant demand 150 kw.
THE DEVITRIFICATION OF “PYREX” GLASSES1
Authors: Morey George W.
Published: June 2006

A study has been made of the devitrification phenomena of three “Pyrex” glasses, which were found to have liquidus temperatures lower than any other known mixtures containing 50 high a silica content. “Pyrex” glass 774 (702EJ), refractive index 1.471, has a liquidus temperature of 1077°, 772 (702P), index 1.486, 1042° and 776 (720GO), index 1.473, 1036°. In all cases tridymite is the primary phase and cristobalite was never observed.
VOLUME CHANGES IN BRICK MASONRY MATERIALS1
Authors: Palmer L. A.
Published: June 2006

Volume changes in brick and mortars attending variations in moisture content and temperature have been studied. There were included in the study 21 cements (both Portland and masonry), 7 limes, and 8 makes of brick received from various sections of the United States. The shrinkage of mortars during hardening and the alternate expansion on wetting and shrinkage on drying occurring subsequent to hardening have been measured. Varying the moisture content produced far smaller volume changes in well‐fired brick than in most of the mortars. Underfired brick expanded appreciably on wetting. It is indicated that differential volume changes between brick and mortar caused by variations in moisture content are apt to be greater than those produced by normal temperature variations. Volume changes in hardened mortars were least in the case of straight lime‐sand mortars.
USE OF LEPIDOLITE IN ZINCLESS GLAZES1
Authors: Davis H. E. , Lueders R. L.
Published: June 2006

It is well known that among terra cotta colored glazes, chromium greens and chrometin pinks are the most susceptible to crazing. This is, no doubt, due to the absence of ZnO from the RO. In an endeavor to introduce into the glaze composition some material of low coefficient of expansion, the natural lithia‐bearing mineral lepidolite was tried with fairly satisfactory results.
SOME EFFECTS OF THERMAL SHOCK IN CAUSING CRAZING OF GLAZED CERAMIC WARE1
Authors: Schurecht H. G. , Fuller D. H.
Published: June 2006

The characteristics of glazes are too frequently regarded as the only important factor governing the resistance of glazed ware to thermal shock crazing. In this investigation it was found that thermal shock crazing was caused, in some cases, by craze‐like cracks which developed in the bodies. The importance of selecting suitable bodies, as a means of controlling crazing, became evident at once when it was found that bodies with a high resistance to thermal shock were not so liable to craze when glazed and subjected to sudden temperature changes as those with a low resistance to thermal shock. In general, glazed ware on which the glazes are under fairly high compression are more resistant to thermal shock crazing than those on which the glaze is under either low compression or tension. Glazed ware which is susceptible to thermal shock crazing may be resistant to moisture crazing and vice versa.
ORIGIN OF THE COLOR PRODUCED ON RED BODIES BY ZINC VAPOR1
Authors: Greaves‐Walker A. McKinley
Published: June 2006

The green color produced by zinc vapor on clays that fire to a red color is not due to the formation of a compound of that color but to the absorption of certain rays of the light spectrum by the yellow zinc glaze and the bluish reduced zone beneath it.

To obtain good green colors it is necessary to have the surface of the body reduced to a good blue color. Greens may be produced during the glazing period and lost during the cooling period due to re‐oxidation of the surface of the product. A zinc process is given in detail.
COLORED JEWELRY ENAMELS FOR ART SCHOOL USE1
Authors: Smith Kenneth E.
Published: June 2006

The process of producing easily fusible jewelry enamels is outlined, batch weights are listed, and the type of furnace used is shown. This process is applied mainly to enameling in cloisons, although the same type of enamels may be used in other modes. The use of enamels in jewelry making and in silver smithing is almost unlimited.2
THE EFFECT OF FIRING TEMPERATURE ON THE DIELECTRIC STRENGTH OF PORCELAIN1
Authors: Monack A. J. , Shardlow L. R.
Published: June 2006

An electrical porcelain body (H and G A1 English china clay, 30%; Tennessee ball clay No. 7, 20%; Buckingham feldspar, 30%; Ottawa flint, 20%) was fired to various cone temperatures and the puncture voltages were determined. The mean values in kilovolts per quarter‐inch thickness were cone 7, 37; cone 8, 51; cone 9, 60; cone 10, 63; cone 11, 61; cone 12, 64. The probable error of the mean in each case is approximately ± 1 kilovolt per quarter inch. The differences of the means between cones 9 and 12 were shown statistically to be without significance. Other conditions remaining identical, it was shown that the most uniform body resulted when fired to cone 9.
THE MODULUS OF ELASTICITY AS AN INDICATION OF THE UNIFORMITY OF ELECTRICAL PORCELAIN1
Authors: Monack A. J
Published: June 2006

An electrical porcelain body of the composition 30% H and G A1 china clay, 20% Dorset English ball clay, 20% Ottawa flint, and 30% Buckingham feldspar, fired to cone 11. showed a modulus of elasticity of 9.54 ± 0.02 × 106 1b. per sq. in. (mean of 164 measurements). A similar body with Kentucky special ball clay substituted for Dorset hall clay gave a value of 10.01 ± 0.02 × 106 1b. per sq. in. (mean of 69 measurements) The accuracy of the measurements was ± 1.5%. The use of the modulus as a measure on. the uniformity of electrical porcelain gave excellent results The variations were expressed in terms of statistical constants such ac: the standard deviation and the coefficient of variability.
MECHANICAL AND THERMAL SHOCK TESTS ON CERAMIC INSULATING MATERIALS1
Authors: Kraner H. M. , Snyder R. A.
Published: June 2006

Simple tests, as developed for daily production of electrical porcelain are given. Laboratory tests are described and results for a number of ceramic insulating materials are given. From these it is shown that mechanical strength and resistance to thermal shock are valuable indications of the mechanical properties of bodies and glazes. Results obtained in testing foreign‐ and American‐made porcelains are compared.
PICKLE ROOM CONTROL FOR PORCELAIN ENAMELING PLANTS1
Authors: Lindemann W. C.
Published: June 2006

A procedure for pickle room control for porcelain enameling plants is outlined and “make up” for four cleaning solutions are given in detail.
OBSERVATIONS ON THE FIRING OF A DOWNDRAFT KEN WITH A STOKER SITUATED OUTSIDE THEREOF1
Authors: Rice W. E. , Harrison H. C.
Published: June 2006

This paper presents some observations that were made during a series of tests on round downdraft kilns fired with a single stoker, and shows the economies that can be expected with this method of firing and the disadvantages that must be overcome.