Page:Popular Science Monthly Volume 91.djvu/909

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Popular Science Monthly

��Incandescent Lamps May Now Be Used to Project Motion Pictures

IT has always been more or less difficult to give motion pictures in places other than a regular theater equipped for the purpose. A lamp has been devised recently which will make motion pictures possible in churches, schools and even in the home. There is nothing which equals motion pictures as a means of popular enter- tainment. Many a small fair, held for charity, would be more successful from a financial point of view if the added attraction of lively motion pictures could be offered.

��A low voltage con- centrated filament lamp has been de- veloped which may be used with a new lamphouse designed especially for motion picture use. The lamphouse contains a double lamp holder with several adjust- ments, a reflector and two sets of condens- ers, one for stereopticon and the other for motion picture use.

A compensator with ammeter and resist- ance regulator is used for alternating cur- rent and a small rotary converter for direct current. Where the amount of electricity consumed is not important a specially designed resistance with ammeter may be used on direct current.

All conditions which might make op- eration difficult may be met by the use of this lamp and lamphouse. A twelve-foot pic- ture has been shown success- fully at one hun- dred feet. The apparatus may be used, how- ever, to project small pictures such as would be suitable for an entertainment to be given at home.

���Switch Details of the low voltage concentrated fila- ment lamp and lamphouse for motion pictures

��893

The War Gardens of Railroad Em- ployees and Station Agents

STATION agents of many railroad com- panies have become war gardeners this year. There are one thousand two hun- dred such war gardens on the vacant lands of the Pennsylvania Railroad. It is ex- pected that the value of the crops raised in these gardens will be two hundred and fifty thousand dollars.

The crops tilled by the rail- road employees aver- age a little less than an acre. They are planted with potatoes, peas, beans, tomatoes, corn, and various other vegetables.

An agent on the New York Central, stationed at Chau- mont, New York, has specialized in beans. He planted a plot one thousand five hundred feet long and twenty-five feet wide on the off- side of the station platform.

���How a tug was raised out of the water by the dredge and held until the propeller shaft was repaired

��A Dipper Dredge That Served as a Temporary Dry Dock

THE propeller of a tug on the Black River was injured. It was necessary to straighten the propeller shaft. But the owners did not want to put the tug in dry dock. So the dipper of a dredge was lowered on to the stern of the tug. Then a cable was passed around the hull of the tug and fastened to the [dipper. When the dipper was raised the stern of the tug was lifted Gut of the water to al- low the propeller shaft to be taken out. The shaft was straightened and replaced in much less time than if the tug had been put into dry dock and with no inconvenience.

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