Tyndall figures, liquid water containing a vapour cavity, were formed in grain boundaries and grains of pure ice by focusing light from a small lamp, after water veins were formed along the intersections of three grain boundaries and the temperature of ice became the melting point. The growing Tyndall figures were observed with a microscope and the shape of the figures in the grain boundaries and the grains was compared.
The shape of Tyndall figures in the grains is shown in Photos 1, 2, 3, 4, 5 and 6 and its feature is described as follows :
1) When the growth rate is slow, the shape is a circular disc parallel to the basal plane. Side face of the disc is parallel to the c-axis.
2) When the growth rate is intermediate, the shape is a disc with perturbation of 6 wave numbers. Side face of the disc may be parallel to the c-axis.
3) When the growth rate is fast, the shape is a truncated cone with perturbation of many wave numbers. The perturbation is nucleated at one of the corner edges of the side face of the cone.
The shape of Tyndall figures in the grain boundaries is shown in Photos 7, 8, 9 and 10 and its feature is described as follows :
1) Perturbation of the figures is sharp and large compared with that in the grains.
2) Cross-section of the tip of the figures is sharp and like wedge.
3) When the growth rate is slow, the minimum wave number of perturbation is found to be 12.
4) When the growth rate is fast, the shape is a dendrite which is similar to the shape of Tyndall figures found in single crystals and perpendicular to the basal plane.
The feature of the shape of Tyndall figures in the grain boundaries is considered to be determined by molecular structure in the grain boundaries. The structure of the grains with which the figures in the boundaries contact does not influence the shape of the figures.

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The general theory and experimental formulae of drift snow transport were studied by measuring the vertical distribution of drift snow transport between the snow surface and a height of 30 cm in the Ishikari Plain, Hokkaido.
As a result, it was found that drift snow transport is influenced not only by the wind velocity but also by the condition of snow surface.
It is considered that the suspended drift snow is transported by turbulent diffusion. According to the theory of turbulent diffusion, log Q representing the drift snow transport has a linearly relation to log Z representing the height.
In the case of saltation drift, on the other hand, log Q is represented by a straight line of Z, according to Kawamura (1948).
In the present case, the relation between log Q and log Z has bent at about 8 cm. The relation is linear above the bend and log Q is linear to Z below the bend.
It was concluded that the drift snow above the bend was transported purely by suspension, and the drift snow below the bend was transported mostly by saltation.

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The paper presents two possible methods for detecting the intensity of snowfall making use of the devices of copper plates of size 30 cm × 30 cm equipped with thermocouples on their surfaces and nicrome wire heaters under them.
One of the methods is based on the measurement of temperature change on the heated plates caused by snowfall when a constant heat flow is supplied to the devices, and the other is based on the measurement of changing amount of supplied heat flow when the temperature of the plates is regulated so as to maintain a constant low value.
It is confirmed experimentally that the first method is quick in response to the falling of snow but is not suitable for detection of a large amount of snowfall, and is capable of detecting the intensity of snowfall up to about 2 kg/m²h in the condition of 03 m/s wind in the report area where atmospheric temperature does not change much during the falling of snow. On the other hand, the second method is confirmed to be not quick in response but effective for detecting widely varying amount of snowfall, and be capable of detecting the intensity of snowfall over 5 kg/m²h in the condition of 05 m/s wind.
Especially, the second method offers an exceedingly effective way of detection because it is not affected much by wind and facilitates the continuous detection of snowfall in the open air.

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As is generally known, after a heavy snowfall over a geothermal field the area of melting snow is observed to expand with time, owing to the heat discharged from the ground. By utilizing a heavy snowfall of a brief duration as a calorimeter, a method to measure the heat discharge from the geothermal field was presented by White (1969). This method named snowfall calorimetry was employed to determine the isopleths of heat discharge in two geothermal fields of Japan, Owakudani, Hakone (Sekioka and Yuhara, 1970) and Sessho-gawara, Kusatsu (Hase, 1971). However, since the values obtained by this method are the sum of the heat transfer in vapor and by conduction through the ground, it was difficult to compare the results with those obtained by other methods.
Recently, Sekioka and Yuhara (1974) developed a simple and rapid method for estimating the distribution of geothermal heat discharge. This method uses a heat budget equation for simple vegetationfree surface, on the basis of the distribution of surface temperature measured with an infrared radiation thermometer and some other meteorological parameters in the geothermal field.
The present paper describes the application of the snowfall calorimetry and the results obtained at the above-mentioned fields, and confirms that geothermal heat discharge patterns show a good agreement between the results obtained by the snowfall calorimetry and by the heat budget method.
It may be concluded that the snowfall calorimetry as an example of utilization of snowfall is a simple, rapid and relatively inexpensive method to estimate the heat discharge of geothermal fields.

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It is observed that in a refrigerator the refrigeratory plate coated with polyethylene glycol is hardly frosted, and that the surface of ice, when contacted with polyethylene glycol, melts gradually even at a temperature as low as below -5°C.
These phenomena are largely ascribed to the molecular weight of polyethylene glycol. When the molecular weight of polyethylene glycol used is 1020, the interface between ice and polyethylene glycol melts even at -14°C.
It is considered that ether groups of polyethylene glycol play important parts in these phenomena.

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In January 1974, a surface avalanche occurred in a mountainous region of Niigata Prefecture, causing deadly damage to Japanese ceder forest of more than fifty years old over 0.9 ha.
The avalanche was released on a steep slope where the average inclination is 35 degrees, and ran down through a valley. The forest consisting of a strip of trees along the valley was 60 m wide, 300 m long, and the height of trees was 820 m with average diameter 33 cm at breast height.
There were 350 trunk-broken trees and 46 uprooted trees in the damaged forest. Trunk breaking took place at the average height of 79 cm from the ground surface.
The uprooted trees remained standing supported by snow cover after the avalanche. Hence, an approximate extent of avalanche cloud (wind mixed with ice particles) was obtained from the heights of borken branches of the uprooted trees. It was estimated at 1215 m high above the snow surface.

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