bluuebunny/crossref_metadata_2025 huggingface dataset:
NOTE ON AN UNUSUAL CASE OF WARPING OF FLAT WARE IN THE GLOST KILN1
Authors: Shecog Thomas A.
Published: June 2006

The warping of flat ware in the glost kiln can apparently be caused by the “pull” of a cooling glaze, provided the glaze solidifies before the body has become entirely rigid.
CLAY SEWER PIPE MANUFACTURE.—IV. THE INFLUENCE OF DIFFERENT SALT GLAZING TEMPERATURES UPON THE COLOR AND GLOSS OF GLAZES OBTAINED ON CLAYS WITH VARYING SILICA, ALUMINA, AND IRON OXIDE CONTENTS1
Authors: Schurecht H. G.
Published: June 2006

Object .—A study was made of the effects of different salt glazing temperatures upon the color and brightness of salt glazes produced upon clays with varying silica, alumina, and iron oxide contents.

Results .—In tests conducted in commercial kilns operating under normal conditions, it was found that increasing the salt glazing temperatures has a tendency to produce duller and darker glazes on clays containing iron oxide.

The brightness of the glazes produced may be approximately represented by the following formula: ‐1.00×1+ 0.376×2 ‐ (1.885 + 0.385(1.01253)(T‐1110))×3= 100G ×1, ×2 and ×3 represent the percentages of silica, alumina and iron oxide, respectively. T is the salt glazing temperature in °C. When G was greater than 0, the glazes were bright; when between ‐0.1337 and 0 they were semi matt; and when less than ‐0.1337 they were matt.

The color obtained may be approximately represented by the following formula: 10.3x1 ‐ 2.65x2+ (14.6 + 54.1 (1.0066)(T‐1110))x3= 100°C

When C was between 0 and 2, white to tan glazes were produced; when between 2 and 3.5, light brown glazes were obtained; when between 3.5 and 4.75, brown glazes were produced; when between 4.75 and 8.2, mahogany colors were obtained; and when above 8.2, dark brown to black glazes were produced.

Clays containing a high iron oxide content should be salt glazed at low temperatures while clays containing a low iron oxide content should be glazed at high temperatures to produce the best glazes. Decreasing the iron oxide and alumina contents will improve the brightness of the salt glazes. High alumina clays will produce darker colors than high silica clays with the same percentage of iron oxide.
SOME UNAVOIDABLE HEAT LOSSES IN THE USE OF PERIODIC SYSTEMS1
Authors: Armstrong Robert H.
Published: June 2006

This paper deals with an approximation of the heat lost: (1) In cooling ware from drier temperature to air temperature and the subsequent reheating. (2) In getting rid of moisture absorbed while ware is cooling and being set in kilns. (3) In a waste heat drier system. All heat values are summed up both for one single burn and over a year's time in tons of average coal representing these losses.
THE OXIDATION OF CERAMIC WARES DURING FIRING.—III. THE BEHAVIOR OF CALCIUM COMPOUNDS IN CLAYS1
Authors: Jackson Frederick G.
Published: June 2006

Previous theories on the formation and decomposition of calcium sulphate as kiln scum are confirmed. Quantitative analyses on the effect of definite heat treatments put the subject on a more definite basis.
COMPARATIVE TESTS OF POROSITY AND SPECIFIC GRAVITY ON DIFFERENT TYPES OF REFRACTORY BRICK1
Authors: Pressler E. E.
Published: June 2006

Comparative data of porosity and specific gravity on several types of refractory brick are presented. Apparent porosity is obtained directly by the water absorption and air expansion methods. Total porosity is calculated from the true specific gravity and apparent specific gravity is calculated from the observed porosity values.

The results indicate (1) a more accurate measurement of open pore space in bricks by means of the air expansion method than by water absorption, and (2) the absence of sealed pores in some types of refractory brick.
NOTE ON SECONDARY EXPANSION OF FLINT CLAY
Authors: Harvey Fred A.
Published: June 2006

Certain flint fire clays show a secondary expansion, which may amount to several per cent, at a temperature much below that at which dangerous expansion begins. Some specifications discriminate unjustly against brick containing fire clays of this the.
THE METHOD OF SELECTING REFRACTORIES FOR MARINE PURPOSES OF THE NAVY1
Authors: Norton H. H. , Porters R. L.
Published: June 2006

Trouble was experienced with refractories when oil fuel supplanted coal in the furnaces of naval boilers.

The selection of refractories for naval oil‐fired boiler furnaces done at the Philadelphia Navy Yard is described.

The Navy's test for refractories (chemical analysis, fusion point determination, and the Simulative Service Test). The Simulative Service Test.—Description of, and its value in obtaining satisfactory refractories. The Navy's “Acceptable List of Refractories.” The results of the Simulative Service Test (about 26% of the refractories submitted passed).
ORIGINAL PAPERS THE BONDING EFFECT OF BALL CLAYS IN FIRED BODIES1
Authors: Sortwell H. H.
Published: June 2006

Seven American and fourteen English ball clays were compared in regard to bonding effect, (a) after burning, in a composition containing no fluxes, at cones 5, 8, 10 and 12; (b) in a semi‐porcelain body burned to cone 8; and (c) in a vitreous china body burned to cone 11. The English clays developed greater strength in the absence of fluxes. The semi‐porcelain and vitreous china bodies containing the imported clays were in general of greater strength than those bodies in which the domestic clays were used, but most of the bodies containing American clays were of good transverse strength.
HANDLING AND STORING RAW MATERIALS TO PRODUCE UNIFORMITY IN A BODY1
Authors: Twells Robert
Published: June 2006

Ceramic raw materials are usually heterogeneous mixtures rather than pure substances. Variations in composition are likely to occur in the materials as received at the plant both within individual carloads and between successive carloads of the same material. Such variations often cause trouble in plants making vitreous porcelain. The article describes ways of avoiding trouble, (a) by rendering each carload homogeneous as it is stored, (b) by withdrawing a material from several lots simultaneously to make the body; in withdrawing from several lots simultaneously, the process should preferably be continuous, one lot being finished as a new one is started, (d) and by keeping accurate records of the materials going into each production batch of body.
THE RELATION OF TEXTURE AND COMPOSITION OF CLAYS1
Authors: Grout Frank F.
Published: June 2006

Twelve Minnesota clays of diverse origin and character, which had been analyzed, were separated mechanically into five fractions, from coarse sand to fine clay, and each fraction was analyzed.

Silica is at a maximum in the find sand portion of most clays. Alumina, iron oxides and potash are at a minimum in this portion, but while they rise a little in the coarse sand, they reach their highest proportion in the find clay portion. Other oxides show less regularity.

An estimate of the minerals is made on the basis of all available information though it may never be possible to tell how much colloidal material is present, making the calculation inaccurate. It seems clear that kaolinite and limonite are larger in clays than in silts, while quartz and carbonates are smaller. Others are less regular.

A detailed comparison of “fluxing constituents” and the temperatures of viscous fusion, led to the suggestion that the behavior of a clay in firing is determined not so much by the total fluxes as by the proportion of fluxes in the fine clay fraction. If this proves to be true, as it seems to be in the Minnesota clays, it should be possible to foretell more accurately than heretofore, the thermochemical and physical changes, on the basis of preliminary laboratory work. Not only the firing of the clay itself, but its effect on admixtures of other clays and its modification by washing can be fairly well estimated from a combined mechanical and chemical test.
THE DEAD BURNING OF DOLOMITE—II1
Authors: Robson James Thomas , Withrow James R.
Published: June 2006

There are many large deposits of dolomite in the United States. These range from the very pure dolomite of Ohio and the eastern states, notably New York and Pennsylvania which correspond very closely to the theoretical formula CaCO3 MgCO3 to dolomites which are very low in MgO content.
A SIMPLE BRICK POROSIMETER1
Authors: Pressler E. E.
Published: June 2006

A brick porosimeter based upon the air‐expansion principle is described, and various considerations of design discussed. The apparatus described is adapted for testing refractory brick, but. the considerations of design presented are general in character. The design is adapted for commercial control work, and the descriptions serve as complete construction references.

Porosity values obtained by the porosimeter and water absorption methods are compared to the values calculated from true sp. gr., to indicate the relative accuracy of the methods.
THE OXIDATION OF CERAMIC WARES DURING FIRING.—I. SOME REACTIONS OF A WELL KNOWN FIRE CLAY1
Authors: Bole George A. , Jackson Frederick G.
Published: June 2006

After a review of the literature, a chemical laboratory study is made of the gases evolved on heating a lower Kittanning fire clay at various rates to various temperatures in a current of pure oxygen. The rates of evolution of CO2, SO2, and SO3 are determined under varying conditions. Determinations of the remaining sulphur in the clay after heating are made. Possibilities as to the chemical mechanism of sulphur evolution are suggested. Plans for continuation of the work are outlined.
COMBUSTION IN KILNS BURNING REFRACTORY WARE1
Authors: Sherman Ralph A.
Published: June 2006

The results are presented of a study of the process of combustion in kilns burning refractory wares, using coal as fuel. The work was undertaken in connection with the investigation of burning problems in the manufacture of refractories, conducted by the Bureau of Mines in cooperation with the Refractories Manufacturers Association.
STRENGTH, ABSORPTION AND FREEZING RESISTANCE OF HOLLOW BUILDING TILE1
Authors: Foster H. D.
Published: June 2006

This paper describes the test methods and gives a summary of the compressive strength and absorption determinations of nearly 350 tests of tile selected from twenty five representative sources. A preliminary report of the resistance to freezing and thawing of tile from seventeen representative sources is also given. The following conclusions were made: (a) The weight of tile per unit of solid material varies from 20 to 30%. (b) The weight per unit volume of material is closely related to the absorption and decreases as the absorption increases. (c) The strength of tile varies with the type of raw material used. (d) The unit strength based on gross area of an end construction tile tested on edge is 38% of that obtained when tested on end. (e) The relation between strength and absorption is not linear but a plotted curve shows increasing gain in strength with a decrease in absorption. (f) Color cannot be taken as indicative of strength. (g) The modulus of elasticity varies from 1,600,000 to 6,060,000 and is approximately directly proportional to the strength and inversely proportional to the absorption. (h) An absorption of 16% apparently marks a very definite line in the resistance of tile to freezing and thawing
BRICK AT LESS COST1
Authors: Richardson W. D.
Published: June 2006

Lowering cost of making brick should increase their use. This is a function of the AMERICAN CERAMIC SOCIETY. Drying brick in kiln is practical and economical. Adapted to clays that stand rapid drying and for common brick, paving brick and stiff‐mud fire brick. History of kiln‐drying system. Open‐top continuous compartment kiln best adapted for system. Description of system in plant at New Hope, Pa. Saving in labor, damage to brick on cars and in deterioration of cars. More compact plant, all under roof.
WASTE HEAT DRIERS FOR WHITEWARE
Authors: Walker Thomas C.
Published: June 2006

This drier is so constructed that the flow of air is transverse to the tunnel. A fan produces a change of air four to six times per minute, drying ten tons of filter‐pressed clay in twenty‐four hours. The drier may obtain its heat either from the kilns, glass or bisque or steam coils, or the use of both.
GAS AS FUEL FOR VITREOUS ENAMELING1
Authors: Clark H. H.
Published: June 2006

The typical furnace described has a burning chamber four feet wide, ten feet long and thirty‐four inches high, no muffle being necessary. The furnace is of the intermittent type. All the details of normal production are given together with a resume of the surprisingly low total cost per hour. A comparison of the average hourly production on 24‐ and 22‐hour bases is given. Also several suggestions are made that will materially effect additional economies in the use of gas for vitreous enameling.
VARIATIONS IN GLASS CAUSED BY HEAT TREATMENT1
Authors: Tool A. Q. , Eichlin C. G.
Published: June 2006

The exothermic and endothermic effects detectable from the forms of the heating curves of a glass vary in magnitude depending on the previous heat treatment. With many of the common glasses, these variations bear a relatively simple relation to any changes in this treatment, but with others the relationship is not so easily established. Some glasses which are exceptional in this respect have a rather high silica content. It is shown in this paper that the previous heat treatment is always the chief determining factor in these variations. It should be possible therefore to obtain considerable information relative to the treatment a glass sample has received by simply studying such curves. It should also be possible to study in the same way, the relative effectiveness of the various heat treatments which may appear desirable.

It is further shown that the density is affected by the heat treatment and in the discussion reasons are given for believing that many of the other properties of glass may be varied by the same means. In this connection some speculative views as to the nature of glass are included as aids toward explaining effects already observed and also for suggesting others which should be sought.
CASTING CONTROL1
Authors: Gerber Albert C.
Published: June 2006

Casting bodies can be toned to a point of success by a proper manipulation of carefully chosen clays, with particular emphasis upon the china clays. A simple casting test will shed light on their individual casting properties. Regulation of casting salts and slip density, and the employment of grog in casting bodies offer means for a certain amount of control, but the preëminent qualifications of a good casting body are a balanced clay content and a correct ratio of clay content to non‐plastics.
THE CHANGES WHICH TAKE PLACE IN SILICA BRICK DURING THEIR USE IN OPEN‐HEARTH FURNACES1
Authors: Rees W. J.
Published: June 2006

A test on silica brick during their use in open‐hearth furnaces is described. Four zones of varying characteristics in a silica brick are noted. A table presents the changes composition and refractoriness which take place in brick used in basic and acid open‐hearth furnaces. With highly converted brick, durability may be promoted indirectly greater structural stability of the roof.
TERRA COTTA IN ARCHITECTURAL DESIGN1
Authors: Laurence F. S.
Published: June 2006

Emphasis is made of the use of terra cotta as an artistic and decorative material. Its successful use demands an architecturally educated talent and a ceramic chemist who appreciates texture, hue and the required colors. The tendency to employ terra cotta to bring out effects of stone masonry design is shown.
NOTES ON TERRA COTTA BODY SHRINKAGE1
Authors: Larkin P. G. , Curry E. R.
Published: June 2006

Notes on method of preparing a terra cotta body, proportioning by volume and using unground material, and method of preparing body, proportioning with ground materials, using disc feeders, are given. Notes on checking laboratory work with these two methods and variation in shrinkage due to amount of water in the body are also considered.
DYNAMIC SYMMETRY AS APPLIED TO POTTERY1
Authors: Richter Gisela M. A.
Published: June 2006

A presentation of the fundamental principles of dynamic symmetry including an explanation of its mathematics and an analysis of Greek vases. The application of dynamic symmetry as applied to the designing of Greek vases is given.
THE COURSE IN POTTERY AT THE PENNSYLVANIA MUSEUM SCHOOL OF INDUSTRIAL ART1
Authors: Curtis Edmund DeF.
Published: June 2006

A description of a simple kiln for firing pottery. The kiln consumes about $1.68 worth of kerosene as against $25.00 worth of city gas which had been previously used. Formulas used at the Pennsylvania Museum and School of Industrial Art are given.
PRESENT AND FUTURE WALLS FOR USE AGAINST MOLTEN GLASS1
Authors: Montgomery Robert J.
Published: June 2006

The early glass pot was made of German clay, which, because of its lack of refractoriness, was later mixed with Missouri fire clay. The war made it necessary to substitute American bond clay for the German which was still used. The batch drifted from one of high silica, such as that obtained with all German clay, to one of comparatively low silica without its being realized. While German clay is now available, it is recognized to be unnecessary.

Aside from going back to a high silica pot and the use of porcelain pots for special glasses, little progress has been made in pot composition. The pot of the future will probably be of clay, but of white firing clays, carefully selected. The structure will be uniform, rather fine grained with greater refractoriness, depending upon greater freedom from impurities. Its chemical composition will be suited to the composition of the glass melted and the temperature of the furnace. The density will be under control and will depend upon the fluidity of the glass at the temperature of melting.
THE USE OF MUFFLE TUNNEL KILNS FOR THE “ARCHING” OF PLATE GLASS POTS1
Authors: Dressler P. d'H. , Strommer L. T.
Published: June 2006

Muffle tunnel kilns have now been in use for five years for the purpose of preheating or “arching” plate glass pots. The use of this type of equipment has brought about substantial savings in labor and fuel, and has increased the average life of the pots by approximately 21%.
THE EFFECT OF RED HEARTS IN FIRE CLAY BRICK1
Authors: Booze M. C.
Published: June 2006

Laboratory tests made on two brands of fire clay brick indicate that red hearts, which are normally considered as being detrimental, add to both the hot and cold strength and would not be objectionable except in furnaces operated at a low temperature, and in which spalling is an important item. Results of load, reheating and spalling tests are given, together with porosity and iron oxide determinations. A short discussion of the causes of red hearts is also included.
AN ANALYSIS OF THE SUSPENSION OF ENAMEL BY CLAY IN TERMS OF THE COLLOID THEORY1
Authors: Poste Emerson P.
Published: June 2006

A detailed review of the literature on the action of electrolytes and organic matter on clays is given.
FINE STONEWARE FROM FLINT CLAY
Authors: Cox Paul E.
Published: June 2006

Based on an observation by Karl Langenbeck1 in his “Chemistry of Pottery” a fine and very dense stoneware fired at cone 9 has been developed with a Missouri flint clay as the principal raw material. The resulting product is non‐absorbing, tough, and a very satisfactory body for ball mill jars, fine art stoneware, and any work where such a body is desired. Plasticity is equal to that of any standard that may be chosen and the body mixture can readily be thrown on the potter's wheel. Control of plasticity can readily be had so that such a body is available for use by any process. The color when fired is that of a poor grade of hard porcelain.
MEDIEVAL EUROPEAN POTTERY1
Authors: Sherwood Robert F.
Published: June 2006

This paper deals with pottery and porcelain from the time of the Fall of Rome through the sixteenth century. Italian pottery before the Renaissance and Majolica ware are discussed under Italian pottery. French pottery is classed under the two heads of Faience and Palissy ware. The influence of the Moors and Arabs upon Spanish pottery and also the origin of Majolica ware is taken up under Spanish pottery. The pottery of England before the Norman period and after the Norman Conquest is discussed. The pottery of Central Europe is dealt with under the head of German pottery. Porcelain is discussed from 200 B.C. on through its introduction into Europe and up to the earliest imitations of porcelain in the sixteenth century.
QUANTITATIVE DETERMINATION OF THE DEVELOPMENT OF MULLITE IN FIRED CLAYS BY AN X‐RAY METHOD1
Authors: Navias Louis
Published: June 2006

Firing clays alone or with fluxes to high temperatures results in the formation of mullite crystals in a highly siliceous vitreous mass. Quantitatively, the extent to which mullite in clays is developed by firing to cone 10 has been determined for Ivory Fat English ball clay, Great Beam ball clay, Jernigan Tennessee ball clay, M. & M. English ball clay and A‐1 English china clay.

The method consisted in procuring X‐ray patterns by the powder method of the clays fired with feldspar as a flux, using mullite as a reference material. The intensities of the lines in these photographic films were then compared with the intensities of lines obtained from a series of mullite and feldspar mixtures, fired to vitrify the flux.

The results given in Table II indicate that each clay develops the maximum quantity of mullite in crystalline form, which the chemical composition of the clay allows.
A METHOD OF CONTROL OF ENAMEL FOR DIPPING FLAT WARE1
Authors: Fusselbaugh R. R. , Sweely B. T.
Published: June 2006

Development of varying specific gravity to control the dipping consistency of ground coat. The necessity of constant mill load and milling. Most efficient milling reached when 1/2% of glass was retained on 150‐mesh screen.
A SLIP PAINTING PROCESS SUITED TO THE CRAFTSMAN WHOSE EQUIPMENT IS LIMITED1
Authors: Cox D. W.
Published: June 2006

The raw materials of the common stoneware business are used. The temperature needed is that of the maturing point of Albany slip, or cones 6 to 9. The kiln should be one designed to stand up under rather high temperatures. The ware is essentially once fired common stoneware decorated with a slip painting process.
SOME OBSERVATIONS ON THE DRYING PROPERTIES OF CLAYS1
Authors: Lindsay D. C. , Wadleigh W. H.
Published: June 2006

This is a preliminary report. After calling attention to some phenomena brought out, the authors discuss the effects of shape, temperature, vapor pressure, humidity and the velocity of air currents as affecting the rate of drying. It is shown that evaporation from the clay sample is directly proportional to surface area exposed per unit weight of the dry clay body and that successful drying is a function of the rate of drying, but a different function for each different type of clay. Data are presented on the relation of transverse breaking strength to residual moisture content for each of several typical clays. The causes of the varying types of drying injuries are pointed out, sample drying schedules are given and a method is suggested whereby the clayworker may without great expense quickly work out for himself in the laboratory the most rapid and safe drying schedules possible for his particular type of material regardless of its character or its source, and to alter his drying practice so as to overcome present difficulties. Brief descriptions are given of the drying cabinet used and of a simple weighing device for automatically indicating, through loss of weight, the amount of moisture already evaporated and the amount of shrinkage the clay has undergone at any moment of observation during the drying process. The information supplied should operate to bring about a reduction in production costs of clay products, and hence of selling prices, to the ultimate consumer. A brief outline of the proposed extension of the investigation is given in the conclusion.
REFRACTORY REQUIREMENTS IN THE GRAY IRON FOUNDRY1
Authors: Moldenke Richard
Published: June 2006

The author calls attention to the lack of information on foundry refractories on the part of both foundrymen and makers of refractory materials. The applications of these materials in foundry practice are enumerated, and the requirements detailed sufficiently to enable the manufacturer to selcct the proper grades of brick and clay for cupola and air furnace operation, as well as for the lining up of ladles.
THE EFFECT OF VARIATIONS IN CUPOLA PRACTICE ON THE LIFE OF THE REFRACTORY BLOCKS1
Authors: MacKenzie James T.
Published: June 2006

This paper discusses chemical, mechanical and physical influences acting on cupola linings and their combined effects. A brief description of common practice in lining, preparation and charging of the cupola is followed by a discussion of the effect of the daubing practice, the character of fuel, metal, flux and blast. The principal point of the paper is the injurious effect of oxidation resulting from thin or rusty scrap and from too high velocity of the blast.
EFFECTS OF COMPOSITION ON THE PROPERTIES OF SHEET STEEL ENAMELS1
Authors: Wolfram H. G. , Harrison W. N.
Published: June 2006

The effects produced by the substitution of feldspar for flint and flint for feldspar together with variations in other constituents commonly used in enamels were studied with reference to their resistance to mechanical shock, thermal shock and acid attack. Tests were made on three series of enamels of twenty each which were applied to 8‐ inch steel dinner plates over a standard ground coat. The enamels of the series containing both flint and feldspar were found to be most satisfactory for general use. Results indicate that enamels having certain excellent properties, making them more suitable for special purposes, may be found in the other two series.
THE EARLY STAGES OF THE SCIENCE OF CERAMICS IN AMERICA1
Authors: Lancenbeck Karl
Published: June 2006

Metallurgical operations and growth of white pottery and tile manufacture stimulated search and analyses of desired clays, by state and national departments, after the Civil War. A chemical relation between composition of pottery bodies and glazes was not surmised in English‐speaking countries, until projected by the writer. Finding the idea in operation in current work of Seger, his methods of investigation were applied to American raw materials and ceramic processes during ten years, without followers in any other country but Germany. Native clay resources, white vitreous ware, standardization of production and control were developed independently, and introduced commercially.

Growth of the large body of ceramic engineers, obligated by immediate demands for technical results, has prevented true scientific study, of common ceramic phenomena, under known laws of modern physical chemistry. Research is entirely empirical, and hand‐books of constants, available to engineers in other fields, are still impossible. To this need of the profession all should now make systematic contribution.
CONVENTIONAL VERSUS NATURALISTIC DESIGN1
Authors: Yancey Mary Lanier
Published: June 2006

Growth from the naturalistic to the conventional type of design is the resultant of certain definite causes. The way for this growth among the people has been made smooth by the change from factory production to individual production in the crafts, and by more widely spread art education. Naturalistic design is based on imitation of natural forms and is enjoyed by the average man because of its likeness to life. The result of this satisfaction is a loss of interest and the need for a conventional treatment. Conventionalism is an adaption of natural forms through the addition of the designer's personality. It is interpretation as opposed to fact. Conventionalism is sometimes misrepresented as being a kind of cleverness and inventiveness, and as a way of hiding bad drawing. Correctly understood, however, conventionalism is construction, not invention, and requires more skill in drawing than does mere representation.
“BALLING” IN CAST WARE1
Authors: McApee W. K.
Published: June 2006

“Balling” is caused, for the most part, by supply of slip being cut off from a thick section of the ware
STUDY OF SEGREGATION IN PORCELAIN FILTER CAKE BY PETROGRAPHIC METHODS1
Authors: Navias Louis
Published: June 2006

The segregation which takes place in a filter cake of a porcelain mixture has been studied in thin sections made from slices of the filter cake fired to cone 10. A lenticular segregation is illustrated by photomicrographs.
THEORY OF EVAPORATION WITH SPECIAL REFERENCE TO THE EFFECT OF AIR VELOCITY AND OF MOISTURE DIFFUSION1
Authors: Tacey A. E.
Published: June 2006

This paper discusses the fundamental principles of drying and shows their practical application to the problems in the drying of clay ware.
PROGRESS REPORT ON THE USE OF ANDALUSITE AS A REFRACTORY1
Authors: Twells Robert
Published: June 2006

An account is given of the development of andalusite for refractory purposes with descriptions of some uses to which it has been put.
NOTES ON THE OPERATION OF DIRECT FIRE TUNNEL KILNS1
Authors: Roehm V. J.
Published: June 2006

The successful application of the direct fire car tunnel type kiln in firing of semivitreous chinaware is described. The bisque kiln firing to cone 9 one‐half down is 332 feet 11 inches long, the placing height at middle of crown being 6 feet and the placing width 5 feet 1 inch. The glost kiln operating at cone 5 has the same placing height and width as the bisque but the length is 301 feet 1 inch long. The ware is placed in saggers as formerly. Natural gas is used as fuel and is supplied to kiln through Maxon Premix burners; an auxiliary fuel oil system can be used in case the gas is not available.

After a year's operation some of the important concliisions drawn are as follows:

The heat distribution is not ideal.

There is no appreciable difference in labor cost a t this plant than in the older ones.

There is a considerable saving in fuel.

The sagger loss is much less than in the older type plants.

The direct fire tunnel kiln has proven siiccessful from the commercial standpoint in manufacturing semi‐vitreous china.
RECUPERATOR OIL SMELTER1
Authors: MacDougall Robert
Published: June 2006

A recuperator was built at small cost to serve a unit of two oil‐fired smelters. These smelters have shown a fuel saving of $2500.00 per year over cost of coal for smelters formerly used, besides saving the labor of one man. An improved product results from better furnace control possible with oil fuel and preheated air for combustion.
SOME OBSERVATIONS IN THE CASTING OF HEAVY ELECTRICAL PORCELAINS1
Authors: Fritz E. H. , Donnenwirta A. L.
Published: June 2006

A summary is given of experiences had in the manufacture of heavy and intricate electrical porcelains by the casting process. Some of the subjects discussed are selec‐ tion and test of clays, mixing of casting slip and its control, and several details of the methods used in casting the ware. Special emphasis is placed on the limits established for viscosity and specific gravity of the casting slip and the general proposition that the slip must be within the limits set for viscosity regardless of specific gravity.
THE FAILURE OF THERMOCOUPLE PROTECTION TUBES IN GLASS MELTING FURNACES1
Authors: Insley Herbert
Published: June 2006

The unusually rapid failure of thermocouple protection tubes when used in glass furnace atmospheres has been found to be due to reaction of the volatilized alkalis in the atmosphere with the aluminum silicates of the tube. Failure of the tubes is due either to differential thermal contraction between the outer reaction layer and the inner unaltered layer of the tube on cooling or to actual corrosion and dripping away of the tube. It is suggested that the use of a much higher percentage of alumina and lower percentage of silica in the tubes may prevent failures from this cause.
AN X‐RAY STUDY OF CYANITE AND ANDALUSITE1
Authors: Norton John T.
Published: June 2006

Samples of cyanite and andalusite have been examined by the X‐ray diffraction method, and it has been found that the structures of these two compounds are Merent from one another and from sillimanite. Upon heating, the compounds are converted into another form which gives the diffraction pattern of mullite or sillimanite.
SEGREGATION IN BINS1
Authors: Garve T. W.
Published: June 2006

The formation of a cone in filling a bin causes ground materials to segregate. We have shown that bins will empty first through the center where the fine material is located and that the sides, where the coarser particles are, will follow through the center afterwards. This takes place regardless of the shape or the angle of the hopper bottom within practical limits. A retarder in center will somewhat correct segregation. To overcome segregation fully, the aforementioned cone formation must be avoided.
THE QUANTITATIVE DETERMINATION OF IRON EXISTING AS FERROSILICON IN ARTIFICIAL CORUNDUM
Authors: Heindl R. A.
Published: June 2006

A procedure is given for determining quantitatively the iron existing as ferrosilicon in artificial corundum.
ECONOMICS OF THE CAR TUNNEL KILN
Authors: Carruthers John I.
Published: June 2006

The advantages of the car tunnel kiln over the periodic kiln claimed by different designers are reviewed. The installation of a car tunnel kiln from an investment standpoint is discussed. Consideration of factory layout, capacity, nature of raw materials and the characteristics of the ware to be fired is essential in planning a tunnel kiln installation. The economic features of tunnel kilns to be investigated before buying are discussed, as are also the problems that may arise in a factory incident to the installation of this type of kiln.
ANALYSIS OF RECENT MEASUREMENTS OF THE VISCOSITY OF GLASSES.—II1
Authors: Fulcher G. S.
Published: June 2006

Viscosity of two series of four component glasses .—The results recently reported by S. English2 are here analyzed by the method used in a previous paper.3 (1) Series 6SiO2, 1.2Na2O, 0.8(CaO+MgO). The temperature at which the difference between the viscosity of a glass and the viscosity of 6SiO2,2Na2O at the same temperature makes a sharp bend is called the aggregation temperature Ta. It seems to correspond to the devitrification temperature. For this series Ta reaches a sharp minimum for the composition 6SiO2, 1.15Na2O, 0.45MgO, 0.39CaO. The viscosity for any temperature also reaches a minimum at or near this composition. (2) Series 6SiO2, 1.1Na2O, 0.9(CaO+Al2O3). The curves are similar to those for the first series, TA reaching a sharp minimum for the composition 6SiO2, 1.11Na2O, 0.81Ca0, 0.14Al2O3.
A METHOD FOR TESTING THE CROSS‐BENDING STRENGTH OF ENAMELS1
Authors: Danielson R. R. , Lindemann W. C.
Published: June 2006

Methods which have been proposed for measuring the strength of enamels, by means of impact tests, are not entirely applicable to enameled flat ware, where the ordinary strains are due to bending of the sheets. An apparatus has been devised by means of which bending stresses can be applied in gradually increasing increments so that the normal behavior of enamels under such stresses can be observed and measured.
METAL POROSIMETER FOR DETERMINING THE PORE VOLUME OF HIGHLY VITRIFIED WARE1
Authors: Navias Louis
Published: June 2006

A metal porosimeter of the McLeod‐Gage type has been developed for use in determining the porosity of highly vitrified ware. The glass capillary is welded directly on to the 20% chrome‐steel metal cap. The metal construction gives a rugged apparatus that can be safely handled for routine work. It is as sensitive as the similar glass apparatus of Washburn and Bunting, but is not structurally delicate. A photograph and drawing with details are included. The suggestion is made that the results obtained by these types of apparatus be expressed as “per cent pore volume,” and that the results obtained by water soaking be specifically named “per cent water absorption” to distinguish between them. Results are given to show that for fairly vitrified ware, the water boiling method gives much lower porosity than the method using air as the fluid.
A LABORATORY KILN FOR OBTAINING HIGH TEMPERATURES1
Authors: Norton F. H.
Published: June 2006

A small, gas‐fired, laboratory kiln is described capable of firing or melting refractory materials up to 1850°C (cone 38). It is pointed out that the flame temperatures reached approach the theoretical values computed from the heat of combustion and the specific heat of the products of combustion.
THE APPLICATION OF PEBBLE OR BALL MILLS IN ENAMELING1
Authors: Lawler Edw. W.
Published: June 2006

A description of pebble mills in enameling is given; details of design and results are discussed.
THE MULLITE CONTENT OF SOME AMERICAN TANK BLOCKS1
Authors: Thompso Fred S. , Vormelker Howard I.
Published: June 2006

Samples of the various glass tank blocks manufactured in the United States were analyzed for mullite by the hydrofluoric‐acid method.
GLASS WOOL AS INSULATOR FOR REFRIGERATION PURPOSES1
Authors: Bates H. C.
Published: June 2006

A new method has been used to measure the thermal conductivities of insulating materials which consists of the observation of the rate of melting of ice in a vessel insulated with the material under investigation. This is done by noting the change of volume of the mixture of ice and water by means of a graduated glass tube connected to the vessel. Results are given for glass wool of various densities, powdered cork, magnesia asbestos composition, slag wool, Sil‐O‐Cel powder, cotton waste and sheep's wool. It is also shown that glass wool that can be kept dry is a very superior insulating material.
MODELED TREATMENT OF POTTERY1
Authors: Fosdick Marion Lawrence
Published: June 2006

This paper is intended as one of a series on processes of decoration of pottery, and is a discussion of modeled treatment, where and how it is successful decoratively and from the point of view of practicality. The process of modeling with coils in low relief is given in detail. Vigorous pattern is used if the glazes are to be matt because of the thicker nature of the glaze which will obliterate subtlety in the modeling. Delicate pattern is used under thinner and more fluid glazes. Formulas are given for one series of vivid colors of a matt glaze and for a treatment of transparent, rather neutral glazes, on a clay red‐orange in color.
CHARACTERISTICS OF PYROMETRIC CONES1
Authors: Fairild C. O. , Peters M. F.
Published: June 2006

For the first time the characteristics of pyrometer cones have been determined under definite and reproducible conditions of heating. The temperatures of the “end points” of a complete set of cones together with their bending intervals were measured at carefully controlled rates of heating in clean air and in various kiln gases. Heated at 20°C per hour in furnace gases free from SO2, the end points of cones 015 to 01 are somewhat higher than those observed when the cones were heated in clean air. Cones 022 to 016 and 1 to 42 were acted upon only slightly by kiln gases free from SO2. There is more significance in the demonstration of the utility of measuring the end points of the cones under accurately controlled and known conditions of heating than in the numerical results obtained.
A COMPARISON OF THE SOFTENING POINTS OF SOME FOREIGN AND AMERICAN PYROMETRIC CONES1
Authors: Geller R. F. , Pressler E. E
Published: June 2006

This paper is a report of results obtained from a study of the softening points of pyrometric cones as made in England, France, Germany, and America. The results are briefly discussed and are also shown photographically so that interested readers can best obtain the specific information they desire from a study of these photographs. The data obtained further indicate that the temperature at which the cones most used in the trade (Nos. 1 to 20) soften can be determined with an accuracy of ±15°C in laboratory kilns of the gas‐fired type, provided good pyrometric equipment is used and reasonable precautions are taken to maintain definite rates of heating. Errors of as much as ±25° can be expected in the determination of temperatures at which cones less refractory than No. 1 or more refractory than No. 20 soften. In the case of more refractory cones this is due principally to the difficulty of maintaining definite rates of heating while, in the case of the less refractory cones Nos. 022 to 01 inclusive, inaccuracies can be attributed both to difficulty of maintaining definite heating rates and to the sensitiveness of the softening behavior of the cones to furnace atmospheres. This is particularly true of the “red series” (cones 010 to 01) the softening points of which are materially affected by changes of a few per cent in the CO2 and SO2 content of furnace gases.
PERSONAL EXPERIENCES AND NATIONAL LIFE AS SUBJECT MATTER FOR DESIGN1
Authors: French Myrtle Merritt
Published: June 2006

Artists who lack ideas for design often resort to copying something made by a different people to express the life of a different age. As a result the design does not express America and is not in harmony with the natural expression of the American home. Many interesting symbolic designs have been worked out in class using personal experiences for the subject matter. Thus the designs have a new interest both to the artist and the public. If American industrial art would encourage the artistic use of the wealth of material in our national life, the products produced would be given a soul which would make them alive.
AN ACCELERATED ABRASION TEST1
Authors: Geister Carl H.
Published: June 2006

A suitable abrasion apparatus is described which is capable of measuring the wear resistance of flooring materials having widely varying physical properties. The requisite conditions of wear necessary to produce results comparable to those obtained in actual service are given. Other abrasion methods and their shortcomings for use in this problem are summarized.
PROGRESS REPORT ON INVESTIGATION OF SAGGER CLAYS1
Authors: Heindl R. A.
Published: June 2006

This paper is the first progress report of a comprehensive study of sagger clays. It includes the results of a preliminary study of clays representative of those used in sagger making throughout the United States. Chemical analyses, and a summary of physical tests, petrographic examinations, and the effect of repeated burns in pottery kilns are given. As a result of this work the clays have been classified into five groups characterized by properties in the fired state. The paper also contains an outline of a proposed intensive and fundamental study of a limited number of clays typical of each group.
A CHEMICAL STUDY OF THE ABSORPTION OF SULPHUR DIOXIDE FROM KILN GASES BY CERAMIC WARE1
Authors: Jackson Frederick G.
Published: June 2006

Two clays rich in scum‐forming bases are studied. One is practically free from sulphur, the other heavily charged with it. Draw trials of these clays are taken from laboratory and commercial kilns at suitable temperature intervals. Commercial firings typify minimum, average and extreme sulphur exposure in coal‐fired kilns. Laboratory firings are in imitation of them. The draw trials are analyzed for water‐soluble sulphates and bases and the percentages of the appropriate sulphates are presented in the form of tables.

Comparisons of results show that the temperature attained has much more influence on the amount of sulphates formed in the ware than concentration, or time of sulphur exposure. Calculations show that even under the most favorable firing conditions, with 0.5% sulphur coal on a 64‐hour schedule of firing, twelve times as much sulphur is available as is actually absorbed. Even under the most severe conditions the concentration of sulphur gases from the coal in the kiln gases is so small, (1%), and the maximum evolution of sulphur gases from the ware is such a small fraction (2.6%) of the volume of kiln gases, that the effect of the former in retarding the formation of the latter according to the Law of Mass Action, must be unnoticeable. It is, therefore, futile to try to avoid sulphate formation with coal as a fuel by seeking a coal low in sulphur. The method of study used is recommended for intensive investigation of firing conditions with the object of attaining maximum economies.
AN INVESTIGATION OF CHECKER BRICK FOR CARBURETERS1
Authors: Parlielee C. W. , Westuah A. E. R.
Published: June 2006

A progress report of an investigation of checker brick for carbureters which is being conducted by the Department of Ceramic Engineering of the University of Illinois in coöperation with the gas companies of northern Illinois has been presented. The methods used in carrying out commercial and laboratory tests and the data so far obtained have been submitted for discussion and criticism. When the investigation has been completed a final report will be made.
USE OF EUTECTICS AS GLAZES1
Authors: Kraner Hobart M.
Published: June 2006

The properties of the high silica eutectics of some of the common ternary systems are given consideration in suggesting them for use as glazes on ceramic bodies.
INTERFEROMETER MEASUREMENTS OF THE THERMAL DILATATION OF GLAZED WARE1
Authors: Merritt G. E. , Peters C. G.
Published: June 2006

The network of fine cracks often seen in the surface of glazed products not only mars the surface but shortens the life and lowers the price of the ware. Since the relative expansivity of the glaze and body is a very important factor in controlling this condition reliable measurements of both are of the utmost importance. Until recently the difficulty has been that the expansivity of the glaze has been measured on specimens of the material melted to glass and drawn into rods or cast in molds of sufficient length. Owing to the difference between this treatment and that received by the material when spread on the ware, it was realized that these methods might lead to unavoidable errors.

By the interference method, specimens 0.2 mm. in length can be measured with sufficient accuracy. Therefore in measuring glazes the samples may be taken directly from the finished ware. In this paper the thermal expansion of glaze materials prepared in the form of drawn glass or cast rods is compared with that of the same material taken from the finished ware. From the measurements, the expected divergence is found to be as much as 20% in the case of drawn glass specimens, and 10% for cast specimens.
A NEW GLASS STONE: Na2O · 3CaO · 6SiO21
Authors: Peck Albert B.
Published: June 2006

Attention is called to a stone of different composition than any heretofore recorded, and but recently possible of identification by petrographic‐microscopic means through the work by Bowen and Morey on the system Na2SiO2‐CaSiO3‐SiO2. Various ways by which attempts were made to determine the composition of the crystals are described and a summary of the optical properties of these crystals from three sources is given. Probable places for the formation of these stones in the tank are also indicated.