Page:Popular Science Monthly Volume 91.djvu/616

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A Wooden Lighthouse Candlestick and How It Is Made

IT is easy to make a wooden candle- stick in the shape of a lighthouse. The one illustrated is about six inches high and about four inches in diameter. The lighthouse is white, with yel- low and red ornamentation; the windows are painted.

The saucer in which the lighthouse stands can be used to receive burnt matches. It is nailed or glued to the lighthouse. Every lighthouse keeper has a daughter. Carve her out separately if you like and glue her into the saucer so as to have her leaving the door. Let her dress be yellow and her belt red.

The depth of the saucer is about two inches. It is painted red. These colors can be varied to suit the tones of the room or the owner's fancy.

A hole is cut in the top of the lighthouse to allow the candle to be placed inside. •

��Popular Science Monthly

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���The lighthouse candlestick makes a pleasing table decoration. The colors are varied to suit the fancy

��Intake

��Getting Rid of the Poppet- Valves on a Gasoline Engine

THE trend of the times in engine construc- tion as well as in every other kind of manufac- ture is toward simplicity. Wherever one thing' can be made to do the work of two or even more parts, nothing is left untried to facilitate the merger. A

western manufacturer has brought out a new gasoline engine in which the poppet- valve, camshaft and associated parts are eliminated and a common rotary valve substituted in their stead to perform the same functions.

When the rotary valve is in a position opposite the apertures in the cylinder head, the burnt gases pass out through the aper-

��tures to the exhaust pipe. The exhaust part of the valve opens when the piston has reached the limit of its downward travel on the power stroke. As the piston approaches the top of the cylin- der in the usual manner, the valve is rotated counter clockwise by means of gears which are securely fastened to the crankshaft and valve respectively. They are in a ratio of two to one and are tied by means of a suitable belt or chain.

The by-pass in the valve remains open until the piston has reached the limit of its upward travel. When the piston starts back the aper- ture in the valve is rotated opposite the aperture in the cylinder head. The influx of gas is through the aperture in the cylinder head, through the rotary valve and its aperture, and through the aperture in the cylinder head to the cylin- der. The valve aperture remains open until the piston has reached the limit of its downward travel.

In this way the mechanism of the engine is so simplified that there is little chance of anything getting out of order and the life of the engine is considerably lengthened on account of the elimination of friction.

��haust

��Section through in- take and exhaust portion of cylinder head on angular line gas supply

���When the rotary valve is opposite the apertures in the cylinder head, the burnt gases pass out through the apertures to the exhaust pipe

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