Popular Science Monthly 



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



Tension Mains without Shock 



^Hi) 



Line of Posts 



M 



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 



