For measuring bin loads, the authors devised and used a small and sensitive pressure cell to find out the vertical pressure distribution of the bed of powder or granular materials filled in a cylindrical bin with a flat bottom.
As the results, it is found that the vertical pressure distribution of fine powder becomes higher in the central part of a bed than in the part closed to the wall. The patterns of pressure distribution of granular materials are very complicated according to the filling method of materials.
These facts can be explained by arch formation in the bed caused by both internal and wall friction forces.

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The density of a Na₂SO₄ smoke particle formed by means of spray-drying of the aqueous solution was determined by measuring the particle size and mass concentration of the spray-dried smoke and further the change due to aging in the sedimentation velocity of the particle. It was found that the particle density is smaller by several times than the bulk density of crystalline solid of Na₂SO₄.
The effect of water vapor upon the stability of the smoke was also examined, with the result that the higher the humidity, the lower the stability.

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Thin layers or tracing points were marked in a two dimensional fan shaped moving bed by using coloured particles. Then, movement of them was observed through the front plate made of perspex and recorded by photographing.
The experiment revealed following flow properties.
1. Particles in the bed flowed down along the line drawn from the origin of the fan shape.
2. Boundary layers were formed near the walls if the surface of the wall would be rough.
3. When the boundary layer was formed, the width of it enlarged linearly according to the moving down of the bed.

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