Our boys; what they can do and how to do it (1893)
Stoddart, William, [from old catalog] comp · New York, Hunt & Eaton; Cincinnati, Cranston & Curts · leaf 196
When motion encounters an impenetrable body it is thrownback so that the angle a, b, c (Fig. 3) will always equal c, b, d. This great law of reflection not onlyapplies to motion, but is also trueof light, heat, and sound. Most motions result from the ac-tion of two or more forces. Flying,swimming,… … 192 OUR BOYS. This fact was discovered by Kepler. Let us draw an ellipse.Drive two tacks into a board a few inches apart. Drop overthem a loose loop of string. Place a pencil inside of the stringand, keeping the string tight, move on with the pencil untilthe ellipse is completed (Fig. 4). Did you…
Handicraft · Amusements · Sports
Internet Archive · Library of Congress · Public Domain Mark 1.0. Free to use for anything.
![An illustration from Nicolai Copernici Torinensis De reuolutionibus orbium coelestium, libri VI : Habes in hoc opere iam recens nato, & aedito, studiose lector, motus stellarum, tam fixarum, quàm erraticarum, cum ex ueteribus, tum etiam ex recentibus obseruationibus restitutos: & nouis insuper ac admirabilibus hypothesibus ornatos. Habes etiam tabulas expeditissimas, ex quibus eosdem ad quoduis tempus quàm facillime caculare poteris. Igitur eme, lege, fruere. [Line in Greek] (1543)](https://img.insideoutlibrary.com/img/200/ia-nicolaicopernici00cope-256-161.webp)
![An illustration from Nicolai Copernici Torinensis De reuolutionibus orbium coelestium, libri VI : Habes in hoc opere iam recens nato, & aedito, studiose lector, motus stellarum, tam fixarum, quàm erraticarum, cum ex ueteribus, tum etiam ex recentibus obseruationibus restitutos: & nouis insuper ac admirabilibus hypothesibus ornatos. Habes etiam tabulas expeditissimas, ex quibus eosdem ad quoduis tempus quàm facillime caculare poteris. Igitur eme, lege, fruere. [Line in Greek] (1543)](https://img.insideoutlibrary.com/img/200/ia-nicolaicopernici00cope-331-222.webp)
