A voyage in space; a course of six lectures "adapted to a juvenile auditory" delivered at the Royal Institution at Xmas 1913 (1915)
Turner, Herbert Hall, 1861-1930 · London Society for Promoting Christian Knowledge · leaf 38
A Sextant used byTycho Brahe. THE STARTING-POINT, OUR EARTH 17 — Keplers Laws. The first is that the planetsmove round the Sun in ellipses. You can easilydraw an ellipse for yourself with two drawing-pinsand a loop of string. Fix the pins in a drawing- … TV/</*/ +£a ruf((e-rV A: Ay^t board and put the loop of string round them, keeping it stretched into a triangle with a pencil point. You can still move the pencil about and it will draw you an ellipse. The drawing-pins are called the foci of the ellipse, and when a planet moves in an ellipse the…
Astronomy -- Juvenile literature
Internet Archive · Gerstein Library, University of Toronto · Public Domain Mark 1.0. Free to use for anything.
