A Special Theodolite deviced for the Measurement of the Duration of Sunshine, according to the Heights of Obstructions on the Ground

[摘要] According to the ordinary sunshine recorder, we can not distinguish the effects from the records produced by clouds and by the obstructions on the ground. In order to distinguish them (from the stand point of my cloud study), I tried to make a special theodolite deviced for the measurement of the duration sunshine, with the consideration of the heights of obstructions on the ground.This theodolite is composed of four principal axes of rotation which are arranged by special relation between their positions.The principle is the same as that of an astronomical telescope, but this small telescope can instantly have an axis of rotation, at any district, parallel to that of the earth.

[学科分类] 大气科学