暗筒式日照计记录比它偏少5 %左右，主要差在日出、日落时段，基本满足业务使用。

The record of Jordan is 5% less than that of Campbell Stokes and most of this error appear at sunrise or sunset. In the main, Jordan is suitable for routine observations.

并从几何、成像原理加以论证，证明了利用感光迹线检查暗筒式日照计方位、水平、纬度安装正确与否，隔光板构造是否精确是可行的。

It is feasible to inspect the azimuth, level and latitude of the dark-tube sunshine recorder, as well as to inspect whether the installation i…