MAKING AND LAYING SUBMARINE CABLES. 14 $ 
these splendid developments of telegraphy; and, therefore, we 
here place before our readers the portraits of four of the prin¬ 
cipal directors of the great telegraph companies, that have 
their chief offices in London (figs. 87, 88, 89 and 90). 
The essential parts of a cable are: 1, the conductor for con¬ 
veying the currents ; 2, the insulating covering of the con¬ 
ductor, by which the current is prevented from passing into 
Fig. 88.—Le Baron Emile d’Erlanger, of the Eastern Telegraph Company. 
the sea. These two materials, when properly adapted to each 
other, form the core of the cable, and this, were it possible to 
place it at the bottom of the sea without damage, would 
suffice for the transmission of despatches. 
This is, in fact, what was done in the experimental cable 
laid between Dover and Cape Grinez in 1850, and also in the 
cable used by the allied armies in the Crimea in 1855; but, 
although in the last instance it was possible to carry on the 
communications for eleven months, it will readily be under¬ 
stood that a wire covered by gutta-percha only, cannot in 
general be left to its fate at the bottom of the water. 
The core of the cable is, therefore, generally covered by 
