Smith, David Eugene, 1860-1944 · Boston, New York [etc.] Ginn and Company · leaf 254
instruments are easily made. The mir-ror is always at hand, and a paper protractor on a LEADING PROPOSITIONS OF BOOK III 243 t? piece of board, with a plumb line attached, servesas a quadrant. For a few cents, and by the expendi-ture of an hour or so, a school can have almost asgood instrumentsas… … ,i» / ■<±**A The Speculum Finaeuss De re et praxi geometrica,:Paris, 1556 Run a line from A to C by standing at C in line with A and P.Then run two perpendiculars from A and C by any of the meth-ods already given, — sighting ona protractor or along the edge ofa book if no better means are…
Geometry
Internet Archive · Wellesley College Library · Public Domain Mark 1.0. Free to use for anything.
