Page:Popular Science Monthly Volume 92.djvu/245

 Popular Science Monthly

Removing a Fuse from the High- A Bridge Built on a Single

Tension Mains without Shock

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��Line of Posts

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��Detachable

���'ANY a line- man who has not taken the trou- ble to put on his rubber gloves has been severely burned while renew- ing a fuse that has "blown." A new "safety-first" fuse box, however, makes it possible for the most careless line- man to perform his task in safety.

The fuse proper is clipped on the cover of the fuse box. ■ When the lineman opens the door, there- fore, the fuse swings back with the cover and automatically disconnects itself from the dangerous spring contacts on the back of the box. The inspector removes the defective fuse and puts a good one in its place without going near those "live'^ spring contacts. The fuse and its parts are very similar to those ordinarily used and are operated automatically without opportunity to produce a shock.

��Heavy spring contacts the only live parts

��Toggle-lock holds door closed and insures contact

��Double-screw

terminals in

ne with bushinqs

Porcelain expulsion bushing.

��Insulator Porcelain bushing"

The fuse simply swings out with the door, safely away from the dangerous spring contacts which are "alive"

��I

��F you have ever crossed a country bridge which swayed and creaked omi- nously underfoot when the wind was high, and which looked as if the weight of the village "fat man" would be more than it could bear, it will not come as much of a surprise to learn that many bridges of this type are very hastily constructed. The one shown in the illustration took all of one whole day to build.

The novel point in the construction shown is that it rests on only one set of posts, which are^et like a row of telephone poles, only nine feet apart. Each pole is supported by two braces, one on either side, and each has a cap on top. The walk boards are long and narrow. One board covers the distance, in length, be- tween three posts.

���This bridge, which is thirty-four feet from the ground, is -built on only one line of posts. Each pole is supported by two braces, one on either side and each has a cap on top

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