Page:Popular Science Monthly Volume 89.djvu/67

 Popular Science Monfhhf

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��An Inverted Steam-Hammer for Drawing Piles

THE time rc'(|iiir(.Ml for drawing sheet steel piling is reduced to seconds by the use of an inverted steam-hammer. Two hundred and seventy-five upward blows per min- ute, with an S^^'.J'-in. stroke are able to remove piles in less time than it takes to dri\-c ihem. This has been proved. The l)uil<ling of the new warehouse for the Pittsburgh and Lake Erie Railroad necessitated the use of cofTer-dams for constructing the foundations. Concrete five feet thick was poured directly against the piling, with no intervening material to prevent adhesion. In this case, ninety seconds was the average time required for drawing these 35-foot piles, which was a minute less than the time used in driving.

The hammer which does this rapid work is sus- pended from the cranebyahea\^ wire cable. A massive strap of steel passes around the anvil block in the form of a loop, the ends uniting below for at- tachment to the pile. A rubber tube con\eys the supply of steam from the crane.

The inverted hammer was also em- ployed in the construction of the Lexington Avenue subway in New York city, with a great saving of time. Not only is the work hastened, but the piles are kept in good condition, being ready for redriving as soon as pulled.

���Six Battleships Go Into Reserve

THE navy department announced recently that six of the older battleships of the Atlantic fleet have been ordered into reserve. They are the Nebraska, New Jersey, Rhode Island and Virginia at the Boston Navy Yard and the Louisiana at the Norfolk Navy Yard. Lack of men was admitted to be the reason for this unusual measure.

��Piles can be drawn in less

time than it takes to

drive them with this

inverted steam-hammer

��When the Fighting Man Dreams

THE harmony of the sleep of the exhausted soldier has but one discordant note, and that is the dream of battle," declares Dr. George \V. Crile. ("A Mechanistic View of War and Peace." The Macmillan Company.) "The dream is always the same, always of the enemy. In the hospital wards, battle nightmares were common, and severely wounded men would often spring out of their beds. An unexpected analogy to this battle nightmare was found in the anesthetic dreams. Precisely the same battle nightmare that occurred in sleep occurred when s<jldiers were going under or coming out of anesthesia, when they would often struggle valiantly against the enemy's surprise attack."

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