The Measurement of the Insolation Duration in Hakone Mountain Range

Abstract

I tried to measure the insolation duration at 18 places in Hakone mountain range by using the Topoheliometer Which I deviced and annoumced in the Geophysical Magazine, Vol. X, No.3 & 4, 1935.
The result of this measurement showed us interesting relation between insolation duration and the shape of mountain range.