無雪期の航空写真から測定または判読できるなだれ発生斜面の固定因子として植生, 傾斜, 方位, 斜面形をとりあげ, 陵線と谷線で区分した単位斜面を分類し, 84のパタンにまとめた。
積雪期の航空写真からなだれを判読し, 84のパタンおのおのについて, なだれが発生した確率を求めた。
この確率を使って固定因子を判読または測定できれば, 積雪深に応じたなだれの発生率を計算することができる。

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ある地域において起る雪崩は, 例年その個所や径路がほとんど決まっているようである。従って道路計画などにおいて雪崩の影響を推定した暢合には, 山頂或は尾根附近で発生した雪崩が, それらの径路に沿って崩落してゆくうちに摩擦や衝突によってエネルギーを失ない, その結果.計画路線に達したときにどのような速度, エネルギー, 衡撃力になるかを調べてみるのも一案であろう。
この報告は某地の道路設計の予備調査として行なったもので, 例年の雪崩糖個所のうち計画路線に影響があるものと思われるものを選び, 鱈時の航空写真によって雪崩の径路を測定し, これにもとずいて本文に述べるような方薯去で, 単位体積の雪崩の速度, エネルギー, 衡撃力を計算し, それによってこの地域の各雪崩の等級ずけを試みた。
又, 当地の昭和42年度の最大雪積時および雪崩最多発生直後の航空写真について, これら雪崩常習個所のうち, 雪崩が計画路線あるいはその近くまで到達しているもののみについて, 雪崩の高さと, 雪崩の量を測定した。

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The structure of the terrain is being constantly changed by continuous geological processes. A corresponding ground plan cartography is a essential basis for a clear representation of the detail of the terrain structure. A terrain photogrametric representation is notable for the sharp measurements and mappings of the irregularities corresponding to the actual detail of the terrain surface.
For the measurements and mappings of the terrain surface by mean of a photogrametric survey, the ground and picture control points are inevitable and those are surveyed through triangulation and analytical triangulation respectively. Actually, it is very difficult to get adequate number of ground control points within the changing area whose speed of changes are very fast and also to apply process of analytical aerotriangulation directly to the picture control points survey for the terrain photogrammetry, because a serial pictures like those for aerial photpgrammetry are not available commonly due to topographic conditions. In short, bridging of the models must be considered instead of that of pictures.
The authors, here, examined analytical picture control points survey for the terrain photogrammetry experimentally. The base-distance ratio which corresponds to the base-height ratio in the aerial photogammetry is usually very small and it affects largel to the accuracy of the measurements. When forward intersections from the known camera positions are applied, corrections for inherent errors of the phototheodolite and distortion of camera lens must be severely considered.

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Several physical sources of errors have been neglected in photogrammetry because of their negligible effects compared to the required accuracy, for example, the minimum size of sensitized particle of film, tangential distortion of lens, irregular film shrinkage, image movement due to the motion of aircraftetc.
But several of them should not be ignored if the higher accuracy is considered, and some of them often produce larger errors than commonly believed.
They shall be pointed out, criticized, and estimated about their effects and correlations, some of them such as colour abberation, and image movement, result the error greater than 30cm, which can not be reduced by simple change of photo-scale.
As the conclusion, reduction of errors beyond 30cm can not be obtained for any photoscale, unless necessary physical considerations are given to those physicalphenomena.

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To interpretate photographs can be said to interpretate what are taken or printed on filmes or on photographic papers.
When we take all things (objects) in cosmos and make images of those, in this case, those contain not only visible ray and invisible ray, but also visible ray can not be recognized, the relation between such objects and images of those make correlation.
In this case, we have to analyze images by using index which comes from a law between objects and photographs (images) and also, confirm what are taken on photographs by using the synthetic effect (result) of analysis.
In those factors, there are factors of proximaty, factor of good form (good continuation, symmetry, closure, connontate) hue, lightness, saturation, quatify and intensity.
But, this time I should like to report about applications of photographic interpretation by using Panchromatic, Rontgen, False Color Film, etc.

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