THE ELECTRIC TELEGRAPH. 



Ten conducting wires are enveloped in a covering of gutta- 

 percha, so as to be completely separated one from another. Thus 

 prepared they are deposited in a square creosoted wooden trough 

 measuring three inches in the side, so that nearly a square inch 

 of its cross section is allowed for each of the wires. This trough 

 is deposited on the "bottom of a trench cut two feet deep along the 

 side of the common coach road. A galvanised iron lid, of about 

 an eighth of an inch thick, is then fastened on by clamps or small 

 tenter hooks, and the trench filled in. 



A section of the trough in its actual size is given in fig. 23. 



Fig. 23. Galvanised Iron Lid, No. 14, Birmingham Wire Gauge. 



Creosoted Deal Troughiug. 



The method of laying the wires in the streets adopted by this 

 company is a little different. In this case iron pipes are laid, but 

 they are split longitudinally. The under halves are laid down 

 in the trench, and the gutta-percha covered wires being deposited, 

 the upper halves of the pipes are laid on and secured in their places, 

 by means of screws through flanges left outside for the purpose. 



To deposit the rope of gutta-percha-covered wires in the 

 trough it is first coiled upon 1 a large drum, which being rolled 

 along slowly and uniformly over the trench, the rope of wires is 

 payed off easily and evenly into its bed. 



So well has this method of laying the wires succeeded that in 

 Liverpool the entire distance along the streets from Tithe Barn 

 145 



