Page:Popular Science Monthly Volume 90.djvu/784

 768

��Popular Science Monthly

��It is necessary to select the proper style of wheel for the fall of water. In this case, due to the small amount of water and head, it was advisable to use an overshot wheel. Where a stream has a greater head or volume of water a turbine wheel would be much better. The water is run into a pipe which terminates in a nozzle, and as the water spurts out at a high velocity the force is brought against cups on the wheel, making it turn and generating the power.

In the installation shown, a flume was made of 2-in. white pine stove pipe, with an internal diameter of 6 in, and the out- side lo in. This conveys the water from the ditch at the head over a distance of 250 ft. to the wheel. The flume is sup- ported on wood frames. A steel gate for regulating the flow of water is located at the end of the flume just above the wheel. The gate is regulated at the wheel and one setting was found to be sufficient at all times, the head being about 14 ft. The wheel runs at about 9 revolutions per minute and the dynamo is driven at a speed of 900 through a gearing to a counter- shaft.

A Small Rotary Pump of Novel Construction

A SMALL rotary pump is very use- ful in a laboratory or for pumping liquids in window-displays. The one illus-

���The rollers turning on the hose press it flat and force the water through it

trated is of unusual and simple construc- tion. It is very efficient and can be run with a small battery-motor. The casing of the pump is made of wood. The materials required are two pieces 6 in. square and }4 in- thick, one piece 4^ in. long and i in. square, one piece 434 i^- long ^"d i in.

��square and a piece cut like the one shown at A, which is curved along the inside edge to receive the rubber hose, B, that is of ^-in. stock.

From sheet metal, cut out two pieces as shown at C and solder them to the shaft D, 7/16 in. apart. At the ends of each pair of arms, rollers % in. in diameter are pinioned as shown at E. These rollers should be made of hardwood with their edges slightly rounded to prevent them from cutting the rubber of the hose. The operation of the pump is apparent from the illustration. — E. R. Thomas.

��for

be

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��A Sheet Metal Door-Stop for Swinging Doors

A DOOR-STOP especially adapted double and single swing doors can quickly made of sheet brass, as shown in illustration. To make one stop it will require a piece of brass 8 in. long and about i}/2 in. wide. This is cut in two

��pieces, one piece

being 5 in. and

the other 3 in.

long. Bend 2

in. of the longer

piece back to

form- an angle

as shown. Drill

or punch two

holes in the longer end for screws to fasten

it to the floor. Make two similar holes,

one in each end of the short piece, and fasten

it to the door as a bumper-plate for the end

of the stop. When the door is opened it is

automatically held in place. A slight

pressure of the foot will immediately release

it. — Jennie E. McCoy.

���Sheet metal stop and bumper on door rail

��A Simple Solution for Cleaning Straw Hats

STRAW hats can be cleaned with the following mixture: 83 Barium super- oxhydrate; 17 sodium disulphite; 88 borax powder. To prevent the hat from becom- ing hard afterwards, dip it in a solution of glycerine and water (about 10 per cent) or wash it with peroxide of hydrogen. The mixture is applied with a small stiffs scrub- bing brush or a large tooth brush until the straw is bright.— C. F. Oursler.

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