Page:Popular Science Monthly Volume 91.djvu/427

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��Hill in San Francisco

N one of the residential sections of San Francisco is a hill so steep that an ordinary trolley car can not climb it. The chief engineer adopted a principle made familiar by many mountain rail- ways. A channel was cut between the rails of each track from the base of the hill to the summit. In each channel was placed a heavy steel cable, which travels over a huge pulley at a point where the two

���Popular Science Monthly 411

Street-Cars Pull Each Other Up This Device Won't Let Your

Hat Blow Off

^TEW hats have a way of blowing off i their owners' heads largely because no two heads are shaped exactly alike, and until the hat has been worn long enough to conform to its owner's head it will not fit properly. A simple device has been invented to make any hat conform to the wearer's head. It is an open-ended tube of cloth made of a single strip of material. The tube contains a strip of sprin g-steel, one end of which is doubled back while the op- posite end extends beyond the cloth tube. When the device is in use this is inserted in the other end of the tube, thus closing the conformer in the hat.

The metal strip has needle-like pro- jections which are stuck through the cloth tube. These serve to keep the cloth attached to the metal strip and may be pushed through the hat crown to keep the device in place. The finishing touch is an elastic cord which is used to tie the ends of the tube together.

By means of this cord the hat is made adjustable to fit the head even when the wearer has just received an inordinate amount of unexpected praise. Its elasticity will take care of any ordinary expan- sion, but it may be untied and loosened up on special oc- casions.

A hat so equipped will be as stationary on the motorist's head as the approved peaked cap and equally as defiant of the wind. .

���Too steep for cars to climb. The diagram shows how one car pulls the other up

��tracks meet and become one at the summit.

The car at the top of the hill and the car at the bottom each pick up the cable. The car at the top of the hill is per- mitted to run under its own power down the slope, thus furnishing the energy necessary to pull the other car up the hill on the opposite track. Compressed air is used to retard the cars when necessary and to pre- vent a runaway should a cable break, which is not probable.

The solving of this problem has placed at the dis- posal of homeseek- ers a delightful section of the city for residences.

���A simple device which may be attached to any hat to make it conform closely to the shape of the wearer's head

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