It was first unveiled by the author that the binding power of adsorbed cations to the surface of clay minerals is increased by drying; and it was named as “fixation phenomenon.” As this is accompanied by the change of zeta potential of the clay surface suspended in water it would be very convincing that the fixation brings out some important change in the clay-water system.
The present paper contains the results of the investigations on the influences of drying of Kaolinitic ceramic materials upon the various rheological and physico-chemical properties of slips and plastic masses. The results were interpreted from the view point of the fixation phenomenon as there is no room for doubt that it is one of the highly important factor governing the nature of clay-water system on drying.
It was confirmed that the drying of kaolin minerals in the form of slips and plastic masses gives a considerable change in physical and chemical behaviors even if they were dried at the temperatures as low as below 50°C, which suggests the importance of the “drying history” not only in the studies of colloid-chemical or rheological properties but also in industrial process control. Furthermore, the possibility of the improvement of casting properties of a certain special slips through drying was pointed out.

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Studies have been made on the conditions of the formation of multicomponent glasses assuming that the one to one correspondence between the glassy state and the glass structure does hold good. This idea is strongly supported by the experimental results of the glass formation range of the systems of borate, silicate, germanate, tellurite glasses, etc.
The conditions of glass formation may be divided into two groups, namely, one puts stress on the geometry of the structure, and the other on the strength of chemical bonds. The former is represented by Zachariasen's rule, and the latter by the mixed bond, and electronegativity theories etc. However, the author pointed out that the conditions regarding the bond strength are implied by those of geometry being necessary for giving glassy state.
According to the picture of glass structure consisting of network and modifier ions Zachriasen's rules are to be applied to the network. The important point in this rule is that the valency of the ion of the network is equal to its coordination number, i.e. Z/S (electrostatic valency)=1. For multicomponent glasses this condition is to be extended as follows:
(1) A cation whose valency is less than the coordinate number, an intermediate ion, may join in the network to take the office of a network former if the condition Z/S=1 is satisfied by making up the difference with the positive charge of an attached modifier.
(2) In order to form glass at least one dimentional continuity should exist in the structure. In addition oxygen polyhedra should share corners, and the central ion of the polyhedra should be small.
These conditions of glass formation are supported strongly by the experimental survey of the area of glass formation covering many polycomponent glasses.
Furthermore, the glass forming range involving b-subgroup ions as Pb may be explained by the idea that Pb-ion itself helps the formation of network of four coordinated Pb.
On the other hand, glass formation range changes by the influence of modifier ions. It was concluded from geometrical calculation that the radius of a modifier ion being most suitable to the network atom is 6 coordination. It the network is formed by four coordinated ions the most suitable radius ratio is R_m/R_n=2, where R_m and R_n are respectively the radii of modifier and network ions.

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In the silica brick used in open-hearth furnaces exist two species of crystals, i.e., one birefringent found at the surface exposed to the temperatures higher than 1470°C and the other in the lower temperature area.
Although it is clear that the former is low cristobalite, but there are some questions whether the latter is high or low cristobalite. It was subjected to X-ray analysis.
The diffraction pattern of the crystals collected from the low temperature zone of the brick showed the broadening of lines. From a graph representing β⋅cosθ against sin θ, where β is the half-peak breadth of the line at the Bragg angle θ, it was confirmed that the broading of lines is due to the effects both lattice distortion and small crystal size, and that the apparent isotropic nature of the crystals may be attributed to the aggregate growth of crystallites of low cristobalite whose size is about 800-2700 Å.

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To make up the vacancy of the published data of the viscosity of high-lead-borosilicate glass in the range of 1.2-10, 000 poises some direct measurement were carried out using the drawing sphere method.
Although, in most cases, the results fit closely on the curves given by Fulcher's equation the experimental values are supposed to be slightly higher.
It was revealed that the log. η vs. temp. diagrams of high-lead glasses at the melting temperatures gave a slope being as high as 2-6 times ordinary glasses. This fact indicates that caution should be paged in estimating the suitable temperatures and in controlling the operating temperatures.
The corrosive action of No. 9 (90% PbO, 10% B₂O₃) on platinum was also mentioned.

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