Stránka:roll 1917.djvu/250

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218 Woodcraft Manual for Boys upper edge on the centre and set it exactly pointing to the Pole Star (a b); that is, the same angle as the latitude of the place, and fix it there immovably; it may be necessary to cut a notch (c) 1n the board to permit of a sight line. The hours eight at night to four next morning may aswell be painted black. As a time- piece, this shadow clock will be found roughly correct. “ The Indians of course used merely the shadow of a tree, or the sun streak that fell on the lodge floor through the smoke opening. The Watch as a Compass In case one desires to locate north and has no compass, a watch may be used. Point the hour hand to the sun. In the morning, halfway be- tween the outside end of the hour hand and noon is due south; in the afternoon, one must reckon halfway backward; for instance, at 8 A. 11., point the hour hand to the sun and find the place half- way to noon. It will be at 10, which is due south. At 4 o’clock, point the hour hand at the sun and reckon halfway, and the south will be found at 2 o’clock. ' The reason “halfway” is used, is that, while the sun makes a course of 24 hours, the clock makes a course every 12 hours. If our timepieces were rational and had a face showing 24 hours, the hour hand pointed to the sun would make 12 o’_,clock noon, always south. If the sun is clouded and you cannot see it, get into a clear open space. Hold your knife point upright on the watch dial, and it will, unless the clouds are very heavy, cast a faint shadow, show- ing where the sun really' is. A Home-made Compass If you happen to‘ have a magnet, it is easy to make a compass. Rub a fine needle on the magnet; then on the side of your nose. Then lay it gently on the surface of a cup full of water. The needle will float and point north. The cup must not be of metal. Lights For camp use, there is nothing better than the Stonebridge folding lantern, with a good supply of candles. A temporary 'l‘o make a more scientifically accurate Sundial. Ice Collins’ “ Book of the Stars," 1). 41. _ ‘HMM‘mn~d—l_k kh—