a suction screw which revolved just underneath the ram. This was a
mass of steel weighing fifty tons and curved upwards like the inverted
beak of an eagle. Erskine had taken this idea from the Russian
ice-breakers which had been designed by the Russian Admiral Makaroff and
built at Elswick. The screw was protected by a steel grating of which
the forward protecting girder completed the curve of the stem. Aft,
there was a similar ram, weighing thirty tons and a like protection to
the after-screws.

The driving power was derived from a combination of petrol and
pulverised smokeless coal, treated with liquid oxygen, which made
combustion practically perfect. There was no boilers or furnaces, only
combustion chambers, and this fact made the carrying of the great weight
of armour under the waterline possible. The speed of the _Ithuriel_ was
forty-five knots ahead when all four screws were driving and pulling,
and thirty knots astern when they were reversed. Her total capacity was
five thousand two hundred tons.

Behind the three forward guns was a dome-shaped conning-tower of
nine-inch steel, hardened like the rest of the armour by an improvement
on the Harvey process. Above the conning-tower were two searchlight
projectors, both capable of throwing a clear ray to a distance of four
miles and controlled from within the conning-tower.

"Well, I am afraid I have kept you waiting, Mr Lennard," said Erskine,
as the platform brought him up again into the conning-tower, in much
shorter time than was necessary to make this needful description of what
was probably the most formidable craft in the British Navy. "We're off
now. I've fitted up half a dozen shells with that diabolical invention
of yours. If we run across a battleship or a cruiser, we'll try them. I
think our friends the enemy will find them somewhat of a paralyser, and
there's nothing like beginning pretty strong."

"Nothing like hitting them hard at first, and I hope that those things
of mine will be what I think they are, and unless all my theories are
quite wrong, I fancy you'll find them all right."

"They would be the first theories of yours that have gone wrong, Mr
Lennard," replied Erskine, "but anyhow, we shall soon see. I have put
three of your shells in the forward guns. We'll try them there first,
and if they're all right we'll use the other three. I've got the after
guns loaded with my own shell, so if we come across anything big, we
shall be able to try