Page:Popular Science Monthly Volume 92.djvu/466

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��Popular Science MontJily

��brass pipe, K, is fitted to the cone with solder. This pipe is so arranged that one end is near the hole of the stop-cock, the other end being a short distance from the top. Its function is to allow the gas to ascend, thus allowing the fluid to enter the economizer freely. As soon as the charge is completed, the stop-cocks are closed and the charging tank is unscrewed. When the operation is completed, the filling tank may be removed and used for charging a num- ber of economizers in a bat- tery, or it may be employed as a single piece of apparatus. — Alfred J. Jarman.

��Making Diagrams for Lantern Slides

PROCURE a thin trans- parent sheet of zylonite or celluloid, and wash it thor- oughly in distilled water. When dry, rub it with a little whit- ing in order to remove any grease. Drawings or writing can now be placed on the prepared plate as easily as if it were paper. Tracings made on the surface of the zylonite with India ink are superior in every way to those made on a gelatinized surface. The finished product should be clamped between two glass plates 334 ^■>y 4 in. The edges may be bound with paper.

A Glass of Water, Some Magic Passes, and Lo! The Water Is Wine

PUT a pinch of finely ground and sifted red Sanders in a glass of water and the liquid will at once assume a red color similar to that of claret. If this liquid is poured into another glass previously rinsed with vinegar, it will assume a tint resembling that of brandy. If a little potash be added to it, it will change back into the original color and finally if a little alum be introduced it will become as black as ink. To a person not ac- quainted with the secret, it would appear as if claret, brandy and ink had been

���A filling arrangement to intro- duce the liquid without waste

��obtained from a glass of water.

The spectators should think that only magic passes were responsible for the astonishing results. The fol- lowing method is good. The performer comes forward showing a glass and passing it around for inspection. Up- on receiving it back, he fills it two-thirds full of water from a pitcher. He then ofifers to allow anyone to taste the water, or tastes it himself to show that it is pure water. The red sanders may be in his vest pocket, and while the water is being tasted, the fingers carelessly seek the pocket and obtain a small pinch, which is all that is necessary to effect the change. A borrowed handkerchief may then be placed over the glass which is then held at arm's length in one hand while magic passes are made with the other, or the glass may be placed on a stand at the front of the stage. The handkerchief is placed over the glass for an instant and the water becomes rosy, the san- ders being introduced while the handkerchief is being adjusted. The other changes are as easily effected and shown, the glass being previously dip- ped in the vinegar, and the alum introduced in the same way as was the red sanders. Wine may be changed into water with equal facility and may be very nicely con- nected with the foregoing trick. The method is as follows: Dissolve 15 grains of permanganate of potash into 1 qt. of water. The resultant liquid will resemble claret in color. Add to this solution 45 grains of tartaric acid. Put into a bottle a few crystals of hypo- sulphate soda and a little water and rinse a glass with this solution. If the per- manganate solution is poured into the glass it will be instantly decolorized. The tartaric acid should be introduced into the pitcher when the handkerchief is withdrawn, and the glass of course should be previously rinsed with the hyposulphate soda solution.

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