AUXILIARY APPARATUS 



411 



the gases in the container suddenly expand, and blow 

 out of the opening. This explosive action of the hot gases 

 effectually puts out the arc formed by the melted fuse. 

 In Fig. 268 is shown a special type of such an expulsion 

 fuse. The fuse container is mounted in a frame which 

 serves as the blade of a switch; the switch is intended for 

 use when the line which it supplies is carrying no load. 



FIG. 268. An Expulsion Fuse, 

 Mounted in a Disconnecting 

 Switch. This fuse is for use 

 in a 15,000 volt line. Gen- 

 eral Electric Co. 



FIG. 269. The Disconnecting 

 Switch of Fig. 268 Shown 

 in the " Open " Position. 



It is styled a disconnecting switch. Fig. 269 shows how 

 the switch looks when open. 



Before leaving the subject of fuses we must say a word 

 regarding the practice of substituting copper wire, nails, 

 etc., for fuses that have been blown, due to an overload 



