Page:Popular Science Monthly Volume 90.djvu/615

 Popular Science Monthly

��599

��Safeguarding Open Drawbridges by an Automatic Car-Stop

��BUMPER -CONNECTING ROD

���time plunged

��DRAWBRIDGES which have been opened too quickly have caused many fatal accidents. Only recently accidents were caused in this manner in Boston and Chicago, where in each case trolley cars that could not be stopped down into the water. Some type of safety stop should be provided on every draw- bridge. That it is perfectly feasible to provide such stops is proved by the ac- companying photograph which show*s the type of stop now being used on a bridge having an upgrade approach. It is the de- sign of a Chicago engineer, J. B. Strauss.

The Strauss safety-stop is placed at the end of the approach to the bridge. When not in, use, it lies flat on the bed of the track. But just as soon as the bridge is opened, an electric motor is automatically started which swings the front end of the striking-frame around on its pivot, until it is raised about two feet above the track. The heavy pivoted end of the heavy steel s t r u c t u re of this frame is held se- curely down. A car which strikes the frame can get very little nearer the edge of the approach than the front of it. In all ordinary cases, the collision will not be severe and the bump will certainly be pref- erable to a plunge into the river.

���A push of the thumb operates the hammer on this Chinese typewriter and moves the spacer

��As soon as the bridge is opened an electric motor is automatically started which raises the bump- er into position

It Takes Four Thousand Characters [to Typewrite in Chinese

A MECHANICAL engineer of Shanghai, China, has invented a Chinese type- writer with a revolving cylinder about six inches in diameter and sixteen inches in length, on which four thousand of the multi- tudinous Chinese characters are distributed over an ordinary matrix.

The "keyboard" consists of a flat table surface upon which are duplicated the type characters. To write the letter "A," for instance, the pointer at the end of a rod attachment is placed directly above the character as it ap- pears on the flat table keyboard. Then a hammer is dropped on a plunger and the impression is made. Several carbon copies may be secured.

The rod attachment which locates the characters on the keyboard also turns the type cylinder and moves the car- riage.

The machine weighs about forty pounds.

�� �