Page:Popular Science Monthly Volume 90.djvu/96

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��Popular Science Monthly

���The wgj^r is shot out from the nozzles at the rate of one thousand gallons a minute

Cooling Off a River with Its

. Own Water ,,

'T^.HE- large manyjacturing

X plants of the'Wdstinghouse Company in Pennsylvania re- quire a whole river of cool water to run them efficiently. The water is needed to condense the*steam which has been used to drive the steam-engines. After serving this purpose in the first few plants, the water becomes hot, and unless it is artificially cooled, it is unfit for further use. In the summer, the temperature of the river often reaches nearly a hundred degrees.

By artificially cooling the river, thou- sands of dollars have been saved because of the increased efficiency of the steam- engines. To cool it off, the river's own water is used as it emerges from the dis- charge-tunnels of the plants. The hot water from the tunnels is forced by two huge centrifugal pumps into a battery of forty-five large nozzles. These are stretched along a large cast-iron pipe, six hundred feet long, and a continuous spray is formed which reaches fnr out into the river. Each spray is directed against another, and the collision breaks up the sprays into particles microscopically small but millions in num- ber which of course, quickly cool as they travel through the air. When they finally fall and- mingle again the whole river is cooled more than twenty degrees.

Such a spray is a rare spectacle when the sun shines on it. The particles of water shot out from the nozzle at the rate of one thousand gallons a minute form a continuous rainbow.

��Felling a Stack of Steel by Means of a Flame

THE felling. of this great steel stack below was accomplished by means of a single oxy-acetylene cutting- torch.

Acetylene-gas was stored under great pressure in a steel tank and as it slowly issued from the tank into the torch it was ignited. As the acetylene burned in the air a great r.mount of heat was devel- oped; but when oxygen was turned on from another tank, the heat then developed was many times greater. In fact, so hot was the small flame that it bit into the solid metal as if it had been so much putty. The places that were cut being carefully selected near the bottom of the stack, the huge column of steel was made to fall in a predetermined spot.

The stack was on the old Harrison Street station of the Commonwealth Edison Company, in Chicago, now being dismantled to make way for a new sixty million dollar terminal.

���This huge steel stack was felled in a few min- utes by the flame of an oxy-acetylene torch

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