A surveyor is a person whose job is to survey land. (土地的) 测量员
noun [专属名词]测量员;检验员
Because light traveling down from a summit passes through many such layers, a surveyor could sight a mirage rather than the peak itself. 因为从山顶向下传播的光会穿过许多这样的层,所以测量员看到的可能是海市蜃楼而不是山峰本身。