FIG. 6. THE NORDENFELT SUBMARINE.
The first submarine to be propelled solely by electricity was designed and built about 1886 by Campbell and Ash, of England. The outstanding features of this undersea craft were the storage batteries, which were formed of 104 cells, and the electric motors, of which there were two and each one developed 45 horsepower.
The boat had a speed of 6 knots, and it had a cruising radius of 80 miles, without recharging the batteries. She is shown in [Fig. 7]. The electric submarine never got out of the experimental class, because of the imperfections of the storage battery at that early date and in virtue of the fact that its range of travel was very limited.
But the experiments were not without value, though, for they led to the use of electricity as the ideal power for undersea propulsion, as you will presently learn.
FIG. 7. THE NAUTILUS, AN ELECTRICALLY DRIVEN SUBMARINE.
What the Gas Engine Did for the Submarine.—Greater effort to use electricity as a motive power for submarines would doubtless have been made had not the gas-engine been invented in 1888.
This new kind of engine was the ideal motive power for propelling a submarine on the surface of the sea, and at the same time it could drive a dynamo which would generate an electric current to charge the storage batteries with.
And when the boat was submerged the engine could be stopped and there was no smoke or burnt gases to escape; the storage battery then gave up its electric current, this energized the motors, and these in turn drove the propellers. This combination system of gas and electric power is used in all submarine boats at the present time.