(noun.) a portable balance consisting of a pivoted bar with arms of unequal length.
整理:莫尼卡
双语例句
They converted the steelyard into platform scales. 威廉·亨利·杜利特.世纪发明.
The compound lever scale on the principle of the steelyard, but arranged to be used with a platform, was invented and came into use in the United States about 1831. 威廉·亨利·杜利特.世纪发明.