视距测量方法的改进

在视距测量中．本文应用上、下视距丝与中丝所夹视角均为17′11″这一原理，证得：上、中、下三丝读数与坚盘读数之间存在着一个多余观测；去除中丝读数同样能求得测站点与碎部点间的平距及高差，且不影响结果的精确性。碎部测量时，对每个碎部点就从根本上减少了一个观测要素。实践证实：此法可节省约15％的碎部测量时间.

AN IMPROVEMENT ON STADIA SURVEY

In stadia sarvey, it is concluded that there is a redundant observation among the observations of upper, middle and lower reticule and the observation of vertical circle. Saving the observation of middle reticule, the horizontal distance and the difference of elevation between stationpoint and detail point still can be computed without any influence upon the accuracy of computedresults. One observation factor can be cut down fundamentally to each detail point in detail survey. It is confirmed in the practice that about 15% working - hours of detail survey can be economized by this method.