Pictomaps were made by tone-line process transforming the continuous tone aerial photography into line type map images.
The various factors which contribute to the quality of the pictomap were discussed.

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The movement of unstable deposits in a wild stream is a important problem to study the erosion control in mountain areas.
We have obtained the cross sections by aeria photograph in order to decide the unstable degree of delposits for several years in a wild stream.

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A new topographic plotter has been developed by Geographical Survey Institute of Japan in cooperation with Nippon Kogaku Optical Co.
The improved model of the instrument is named Nikon Plotter.
Nikon Plotter is designed for one man operation. It consists of four main systems; projection system, intersection system, drawing table, optical system. Explanation of the systems is given with illustrations and photographs.
Accuracy of the instrument is reported. It is also discussed how PG-2 principle can be adopted into the instrument.

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