Page:Popular Science Monthly Volume 90.djvu/212

 196

��Popular Science Monthly

���The car-puller is located beside the track and is belted to a motor or to a line-shaft through a clutch-pulley

��Car-Pullers Take the Place of Switch Engines

SHIFTING railroad freight cars at in- dustrial plants by hand labor is both expensive and slow. With a switch engine it is still more expensive. ' These are two reasons why car-pullers are -coming more and more into use. The car-puller consists of an electric motor which drives a cable drum, winch-head or capstan around which a rope or steel cable attached to one freight car or a string of cars is fastened. When the drum revolves the rope tightens and the cars are slowly pulled toward the machine. In one plant a twenty horsepower motor was strong enough to handle ten loaded freight cars on a slight down grade and to shift from six to ten loaded cars daily. The maximum length of haul is about three hundred feet. The car-puller shown in the accompanying illustra- tion is capable of hauling from three to five loaded cars. It is small and very compact.

��favored blue-black variety and is guaranteed by Nature not to fade. To be sure, it is rather a long way off, being located in Algeria, but that is not much of a considera- tion.

The ink river is formed

by the union of two

streams, the water from one

of which is impregnated with

gallic acid and the other with

iron. These are the two

necessary elements of the

best ink.

The earliest ink of the man- made variety was prepared by suspending a bag of soot or other carbonaceous ma- terial in some sticky solution such as glue or varnish. Later the cuttlefish was found to yield a secretion which could be used for the purpose. But the modern blue-black ink is obtained from gallic acid, usually from China or Turkey galls, mixed with iron sulphate. This is the kind with which the Algerians might flood the market.

��Mahogany Cigarette Mills That Pass the Cigarettes

A STRIKING and convenient accessory for the smoking room is a cigarette mill. One type is turned by the hand as shown in the illustration; at each revolu- tion it turns out a cigarette from the "hopper." In the stork type the user pushes the button; this causes a panel to open, and the stork puts his head down into the in- terior, takes out a cig- arette and hands it to you politely.

��Is Ink Becoming Scarce ? Not in Algeria

WITH the price of ink soaring to keep pace with paper, and the cuttle-fish seemingly on strike, the manufacturers of writing fluids will probably be glad to have their attention called to a river of the purest kind of ink waiting to fill the demand from a seemingly inex- haustible source. It is of the

���To get a cigarette you turn the mill at the left or press the button at the side of the stork

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