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'ent was measured by the heating effect 

 ipon compound strips of metal. The 

 leat caused the strips to deflect, and the 

 notion was recorded by a pointer. There 

 vas also shown a safety fuse which 

 vould be melted, and thus interrupt the 

 current when it exceeded a predeter- 

 nined limit. With a pressure of 2,000 

 rolts it was necessary to have a long 

 use- wire, because the arc set up upon 

 he melting of the fuse would remain, 

 mless its length were considerable. As 

 l further precaution to make the arc 

 :ease, the wire itself was within a slot in 

 he slate base, and the arc was thus sub- 

 ected to the chilling effect of the cold 

 ilate. He was able to exhibit a portion 

 >f a switch of Mr. Lowrie's installation 

 n Kensington, by which the connection 

 >etween the different dynamos and cir- 

 uits could be effected. Also an ex- 

 remely neat arrangement for showing 

 he insulation of the cables. It was 

 lothing more than a Geissler tube. One 

 >ole was put to earth, and the other was 

 >ut to any one of the circuits which were 



