Page:Popular Science Monthly Volume 89.djvu/789

 Popular Science Monthly

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��A Scheme for Soldering Metals Difficult to Join

MANY times wluMi soldering together different metals which do not join easily it is better to put acid on each piece and fasten the solder to it separate- ly. The pieces can then l)e soldered to- gether without using more acid.

This method is especially advanta- geous for fastening two pieces together, where if acid were used, it might run into places difficult to reach with a cleaning cloth so that it could not be wiped away and would corrode the metal.

A Heat Deflector for a Hot Air Register

A SHEET metal canopy placed over the ordinary hot air register will direct the heat toward the bottom of the

���The metal canopy deflects the hot air outward and down toward the floor

room where it is most needed. Strips of fairly heavy metal about 7 in. wide are cut as shown in the illustration. The back is turned in at an angle of 90 deg. and fits in behind the register. After the canopy has been bent into shape the screws in the register are loosened and the back slipped behind it. Then the screws are replaced. — E. C. Stilweli,.

��How to Straighten the Crooked Straws of a Broom

TAKE a pail of boiling hot water and completely immerse the straw end of the broom for ten minutes. After the straws have become completely soaked,

��withdraw the broom and suspend it by the liandle. When the straws are dry they will be found to be perfectly straight. — E. Huntsman.

��An Automatic Cleaner for Bicycle Hubs

HUBS of bicycles readily collect dirt, and because of the spokes they are very hard to clean. With the little

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���The weight of the chain link keeps the leather from turn- ing with the wheel

��de\'ice illustrated the cleaning is done automatically and the surface kept polished. The device consists of a piece of leather shaped as shown, then hung over the hub, the ends being fastened with a link of chain. This link besides holding the leather on the hub is also conve- nient for repairing a broken chain in an emergency. — M. J. Silverstein.

��An Improved Force-Filter Which Is Easily Cleaned

MOST force-filters, used for rapid quantitative work, catch the fil- trate in flasks, which are often hard to clean after a filtration, especially if some of the precipitate passes through the filter-paper.

This disad\'antage can be overcome b>- catching the filtrate in a beaker under a bell-glass, with a top for a two-hole rubber stopper. A funnel is inserted with a glass tube which is connected b>- means of a rubber tube to an aspirating-pump. If the suction is strong, a platinum cone should he placed in the funnel to prevent the paper from tearing. The glass or metal plate, upon which the bell-glass rests, should have a slight coating of some sticky, pasty material, such as that used on the disk of an exhaust pump, which will render the contact perfectly air-tight. — Ed\v.\rd Mutch.

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