Page:Popular Science Monthly Volume 90.djvu/298

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��Popular Science Monthly

��A slight tap of the paper will cause the filings to take on the lines of the magnet force beneath the paper, as shown in the illustration. It is necessary that the printing paper be handled in a dark room and exposed to a light only after the filings have taken on the lines of force. After the paper is exposed to the light long enough it is develop^ in the usual manner. Blue prints may be made in the same way but the paper must be printed in the sun- light. — Alexander V. Bollerer. -

��A Gas-Lamp Riddle for a Store Window Display

A GAS-FIXTURE dealer in Brooklyn, N. Y., who was something of a window display expert as well, recently hit upon an

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���The lamp is suspended by wires and is with- out visible connection with the gaspipe line

ingenious scheme for attracting attention to his window. From an inverted U-shaped gaspipe he suspended by two fine wires a gas-lamp of the inverted incandescent- burner type. The wires were attached to a T-joint from which the lamp hung. The lamp burned brightly and attracted crowds just as he knew it would. Nobody could solve the riddle as to how the gas got into the lamp? The answer was this: Two tiny holes were bored in the upright posts of the U-bend. The holes were aimed exactly at the holes in the end of the gaspipe T-joint. Below the window, the U-joint was con- nected to the gas-main. When the gas was turned on, it shot from the two small holes straight into the ends of the T-joint and the lamp was lighted.

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��Cleaning Steel Pens with a Glycerine Sponge

THE illustration shows a European idea that is said to be a decided improve- ment on ordinary pen-wipers. It rubber sponge, wet with glycerine and placed in a glass holder. The sponge does not dry and is always ready. Glycerine takes up liquids readily, and it absorbs the ink from the pen by a mere con- tact or capillary attrac- tion. A thin layer of glycerine adheres to the pen and preserves it, making it take the ink at once when dipped.

���Glycerine-dampened sponge pen-wiper

��Bending Brass and Copper Tubing Easily

THE following is an easy method of bending brass tubing so that it will not kink or split in the seams: Plug one end of each tube with a piece of soft wood. Place the tubes in an upright position and fill them with hot melted resin. The resin may be heated in a glue pot or a similar utensil. When cool the tubes can be bent to any desired shape. After bending, the resin is removed by holding the tube with the tongs or a rod and applying a blow torch, bunsen burner or other flame. The resin will run out and the tubing will retain its shape. — G. W. Jager.

��A Cigarette Holder Which Expels the Burned End

THE illustration shows a new cigarette holder fitted with a convenient device for expelling the burned end. This consists of a split ring which fits in the end of the holder as shown. On the outside is a pro- jection joined to the ring so that by push- ing on it the split ring can be slid par- tially out of the holder. The cig- arette is inserted when the ring oc- cupies the inside po- sition. To throw

���The split ring holds the cigarette end

��out the burned end, slide the button for- ward. This opens the split ring and frees the end of the cigarette.

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