In Part I of this series of papers (J. Ceram. Assoc. Japan, 68 [9] 194-204 (1960)), we have described the effect of different methods of kneading clay bodies on the orientation of particles. The present paper deals with the difference of texture in a suspension-insulator green body. The dried body was cut along different directions to get the test pieces for measuring the particle size distribution, DTA, imbibibitional swelling in water, thermal expansion and porosity, and also the thermal expansion of fired specimens.
From a detailed study of the effect of plastic forming method of the body on the texture, not only the orientation of clay particles was strictly different partially, but also non-plastic grains were concentrated to interior parts of a body associated with flow-phenomena of a plastic mass.

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Hot-pressing of Linde C alumina was carried out at the temperature range from 1700° to 1900°C. Average grain size, bending strength and transmission of light were measured. The rate of grain growth for hot-pressed alumina was compared with that for ordinarily sintered alumina.
Results obtained are as follows:
(1) The rate of continuous grain growth of alumina during hot-pressing was smaller than that during ordinary sintering. In other words, continuous grain growth was hindered by pressing at high temperatures. This phenomenon might come from the concentration depression of lattice vacancies caused by compressive stress.
(2) Continuous grain growth of alumina during hot-pressing was retarded by addition of 0.16wt% magnesia.
(3) Alumina was subjected to discontinuous grain growth easily in carbon-monooxide and nitrogen atmosphere.
(4) The bending strength of specimens was in the range from 20 to 67kg/mm², and was inversely proportional to 0.6 power of the average grain diameter.
(5) Hot-pressed alumina specimens showed good translucency. Transmission of light was about 55%/mm for a specimen hot-pressed at 1900°C for 60 min.

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The subject of the swelling properties of clay-water system are valuable to know the working properties of clays for ceramic uses and the effects of treatments of raw ceramic bodies such as sponging.
An apparatus was devised for measuring the linear imbibitional swelling expansion of clays. It is obvious that the swelling of clays is rather complicated physical phenomenon, so that it depends on various factors.
Several important phenomenon were derived from the experiments, and the results obtained are summarized as follows:
(1) Swelling expansions of highly dispersive clays such as Kibushi-clays, Gaerome-clays, and bentonites are much greater than kaolins, pyrophyllites, sericites, or milled pottery-stones.
(2) In general, highl plastic clays show high swelling expansions, but the reverse is excepted.
(3) Organic matter exerts an interesting effect upon clay swelling. Generally, organic matter has a high absovptive capacity for water, but some clays rich in organic matter do not always show high swelling expansions.
(4) The swelling expansion of clays increases as the temperature of water increases.
(5) The swelling expansions are affected by the drying temperature of clays.
(6) In general, the swelling expansions of clays in salt solutions conform to the lyotropic series of cations. But the quantity of the expansion varies with the concentration of salts. Kaolin do not expand in salt solutions.
(7) In alkali solutions clays show high swelling phenomenon, but do not show in acid solutions. Kaolins display swelling phenomenon in alkali solutions.
(8) The relations between exchangeable cations and degree of swelling are differ from clays.
(9) The swelling expansions of bentonites in water show four steps.

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Arsenic-sulfur glasses can be directly prepared in the film form by thermal evaporation under normal pressure employing an evaporation outfit devised so as to prevent oxidation by atmospheric gas. The prevention of oxidation is made by contacting a plane target of a moderate thickness with the top edge of batch container. The moderate thickness of target is in the neighborhood of 0.05mm when the target material is aluminum.
The preparation of transparent glass films requires control of the target temperature. In general, during an evaporation the batch has been heated up to 120°-150°C higher than the target temperature. In the case of As₂S₃ batch, target temperatures below about 345°C have been resulted in opaque and/or crystalline films whereas at temperatures of 345°-365°C transparent glass films of good quality have been obtained. Target temperatures above about 365°C, however, cause the formation of bubbles in the film. Transparent glass films can be successively obtained by replacing the target during the continuous evaporation. The optimum temperature of target is shifted toward the lowered temperature and at the same time the optimum temperature range is widened with the increase in the sulfur content of batches. In the case of the batch of As₂S₃+11S in mole ratio, the optimum range of target temperature has been 250°-290°C. The direct preparation of transparent glass films from the batch mixture of arsenic and sulfur can be made by the almost the same temperature control of target as in the case of the batch of As₂S₃-S system. The rate of deposition of the glass films has been about 0.01mm/min. when the difference in temperature was 120°-150°C between target and batch. When the material of target is aluminum, the dissolution of the target in dilute hydrochloric acid is one of the convenient ways of separating the glass film from the target. In this way, transparent glass films of 0.05-0.3mm thickness have been successfully obtained without special care.
The arsenic content of transparent glass films obtained is increased with that of batches, and is increased with raising the target temperature within the optimum range. The arsenic content of the glass films is increased to some extent by the continuous evaporation and successive depositions of the film on new targets. The composition of the films obtained from As₂S₃ batch has been in the range of about 59 weight% arsenic (As₂S_3.2) to about 63 weight% arsenic (As₂S_2.7), and the compostion of the films from As₂S₃+11S batch in the range of about 23 weight% arsenic (As₂S₁₆) to about 37 weight% arsenic (As₂S₈). In this paper, the arsenic-sulfur mole ratios are expressed in the form of formulas for each glass film.
The X-ray diffraction measurements on the transparent films of the compositions near to As₂S₃ and As₂S₈ and on the ircrushed powders show that these films are glassy. A few additional properties observed from glass films of the composition ranging from As₂S_2.7 to As₂S_8.2 are as follows: Infrared transparent up to about 12μ (transmission=about 70%); no appearance of devitrification after the heat treatment in moist air at about 95°C for 9 hours and/or after the exposure to moist air at room temperature for 1 year; inert to both hot water and 10 weight% hydrochloric acid at about 95°C (weight loss after 9 hours=10^-4-10^-5g/100g of reagent); high electric resistivity (volume resistivity at room temperature=10¹⁵-10¹⁶ ohm-cm).

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