Page:Popular Science Monthly Volume 92.djvu/934

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918

��Popular Science Monthly

���The fumes of the volatile liquid are forced into the open- ings of the tunnels and kill every ground squirrel in them

Making a Gas Attack on the Pesky Ground Squirrel

FULLY a score of men, each carrying a mysterious long-handled container resembling a churn with an end of hose attached, have reached the field. They do not march in close formation, but scatter in every direction, apparently in search of something. First one then an- other stops, puts down his churn, fumbles with the hose and then grips the handle of his churn and begins to work it up and down like the handle of a bicycle pump. What are these men doing and why are they doing it? Is this war? — Yes, it is war — not against a nation, however, but against the ground squir- rel, feared because of its destructiveness and be- cause it is known to be a carrier of the germs of the bubonic plague and other diseases.

Under the direction of the United States Public Health Service these men are sent out to extermi- nate the ground squirrels by pumping the fumes of carbon disulphide, a high-

Iv volatile and inflamma- I*!' 'MTr'J^nfmT

- , the old servmg mal-

ble liquid, into the tunnels i^t and his improved

dug by the squirrels. substitute for same

��Saving Time in Insulat- ing Electric Cables

EVERY motion picture studio uses hundreds of yards of electric cable. It is important that the cable shall not be damaged when it is walked on or when a truck should run over it. Electric cables are therefore wrapped to protect them — • an expensive business. To simplify and cheapen the process, William T. Kearns, mechanical superintendent of the Balboa Motion Pic- ture Company, has invented a clever de\dce.

Kearn's invention consists of a reel attachment for a serving marlin. A reel of twine is held in a metal frame and the twine is wound off the reel around a marlin onto the cable. The marlin is nothing more than a wooden mallet grooved to fit against the cable, and the frame holding the spool of twine is fast- ened upon the handle of this marlin. The device makes it possible to bind the twine tightly on the cable.

The device saves labor. In the older and more tedious method, one man didthe wrap-

ping while another

passed the twine around the cable. With this device one man does both.

��This picture shows how the new serving reel is used for winding a cable by one man

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