Page:Popular Science Monthly Volume 92.djvu/859

 Popular Science Montkhj

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��The doors of large public garages have to be opened very frequently and at all hours of the day or night. This neces- sitates constant attendance upon them. The device shown in one of the illus- trations enables t he clerk or stenogra- pher in the garage office to open or close the heavy gar- age doors without leaving her desk, simply by pressing a button. The de- vice consists of a small electric mo- tor geared to a cable-drum. The current is controlled through a set of push buttons and a relay. When the starting button is pressed, the current is sent through the motor which operates the drum and, by winding up the cable, pulls open the door until a metal contact on the door itself comes into play against a switch-bar, supported by the small overhead frame that carries the motor. This shuts oflf the current and leaves the door open. To close it, a second button is pushed and the door is closed in the reversed order, with a simi- lar switch to shut off the current when the door is closed.

It is self-evident that the ease with which large doors

���This garage has folding doors that slide in grooves and require little "elbow room"

��may be operated depends primarily upon the nicety with which all parts are fitted and upon the quality of the materials used. An ounce of prevention being worth a pound of cure, it would be poor economy to resort to inferior labor or material to save a few dollars on the initial expense, only to have to pay a repairman a more or less heavy bill after a short time.

���This sliding garage door swings around the comer and requires very little inside space

��An Automobile that Got Its Power from the Street Mains

AN automobile provided with a com- ^ pressing plant by means of which gas could be taken from mains in the streets and compressed into the cylinders, in which it was stored as fuel for the machine, is the work of W. H. Dunkley of Bir- mingham, Ala. The plan included the employment of charging stations erected in the streets. Payment for the gas could have been made by means of slot me- ters and gas pass keys.

The Dunkley automobile was made in the early days of the use of coal-gas as a fuel for machines. It had a twin-cylinder opposed horizontal engine and the port- able gas compressor was made up of two water-cooled cylinders at right angles to and above the power cylinders. The cylinders in which the gas was stored were of the standard type used for oxygen. An idea for fitting hollow disk wheels as auxiliary reservoirs for gas was also evolved by Mr. Dunkley.

���D i f f er ent styles of roll- ers that are used for the sliding doors of garages

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