spherograph

📖 中文释义

  1. 球面三角计算盘
📘 English Definition(英文释义)
  1. n. An instrument for facilitating the practical use of
  2. spherics in navigation and astronomy, being constructed of two
  3. cardboards containing various circles, and turning upon each other in
  4. such a manner that any possible spherical triangle may be readily
  5. found, and the measures of the parts read off by inspection.