Page:Popular Science Monthly Volume 91.djvu/937

 �FOR PRACTICAL WORKERS

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��Chemical Flasks Made from Electric Light Bulbs

CHEMICAL flasks are indispensable around the laboratory. Very service- able ones can be made, at practically no expense, from worn-out electric bulbs. Since the bulbs are manufactured in various sizes, it is possible to construct flasks of many dimensions according to the sizes of the electric globes.

The essential materials are a Bunsen burner and a three-cornered file. If a Bunsen burner is not available, any burner giving a hot blue flame can be utilized in- stead. Hold the brass base of the bulb in the flame for a few seconds, until the cement surrounding the glass has melted sufficiently to enable you to pry the base off with the pointed end of the file. Allow the glass to cool; then with warm water clean off the cement that still adheres to the bulb.

Carefully make a scratch with the file around the circumference of the bulb where the globe proper is sealed to the filament. A light blow will separate the filament from the bulb. If the mouth is left rough, it may be smoothed by revolving it in the flame. While the bulb is soft at its mouth, it may have a small taper put on it with the sharp end of the file. When it has cooled, hold the mouth of the flask in a cloth, and permit the large end to revolve in the flame, taking care to heat the glass evenly until it softens. Have a clean dry slab of marble, slate or similar substance at hand, and press the flask down on it evenly so that the flask can stand by itself.

After a few flasks have been com- pleted, they should be placed in a strong salt solution. Heat the solution, while the flasks are in it, bringing it gradually to boiling point; then when the brine has cooled, take the flasks out. They are then ready for use. — Herman Neuhaus.

��A Concrete Mixer Made Out of an Old Mower

AN old dismantled mower constituted jTjl the foundation for this unique con- crete mixer. One mower wheel was planted in the ground and weighted with rocks, while the other was supported on a beam to stand the axle at an angle. The sickle driver head was removed and a band wheel put in its place. A rough wood box constructed of matched lumber to make it water-tight was fastened to the spokes of

���The axle of an old mower set at an angle and used to revolve a box for mixing concrete

the upper wheel. A hinged cover was fastened to the open end. In this the cement was whirled.

A portable farm engine was used for the power, which was connected up to the mixer with a belt. — J. E. Grinstead.

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