192 



THE ELECTRIC TELEGRAPH. 



that, when the latter is deflected by the wind, the line-wire, 

 in swinging, may not come into contact with it. The hook 

 Q, Fig. 102, held in the loop p of the bracket M M', is 



Fig, 102. 



twisted so that, in case of a sudden jerk, the line cannot be 

 thrown upwards and the insulator disengaged from the 

 bracket. The carrier o is also bent over the wire, to prevent 

 the line jumping out. The bracket is formed so that the 

 insulator hangs quite free of the stem. 



The Spanish insulator consists of a porcelain bell, b, Fig. 

 103, supported by a strap of hoop-iron fitting into the groove 

 g, and screwed to the post. The line-wire is carried by a 

 stalk cemented into the inner recess of the bell. The chief 

 merit of this insulator is its cheapness. In climates like 

 that of Spain it answers well enough, but would be utterly 

 useless in England, where the atmosphere is always charged 

 heavily with water vapour, which, condensing on the surface, 

 would soon occasion a material loss of current. 



Varley's insulator is that most commonly employed in 

 England. It consists of two separate red -earthen ware cups, 

 a and , Fig. 104, cemented together with sulphur. The 



