been in the same space ashore. The vessel contained
sufficient air to last them several hours, and when it became vitiated
there were always the tanks of compressed air ready to be drawn upon.

Except for the hum of the motor and the slight clank of the
steering-gear, all was silent; none of the noises of the outer world
penetrated the watery depths; neither the slap of the waves, the whir of
the breeze, the hiss of steam, nor rattle of rigging accompanied the
progress of this submarine craft. As silently as a fish, as far as the
outer world was concerned, the _Fulton_ crept through the submarine
darkness. If an enemy's ship was near it would be an easy thing to
discharge one of the five Whitehead torpedoes she carried and get out of
harm's way before it struck the bottom of the ship and exploded.

In the tube which opened at the very tip end of the nose of the craft
lay a Whitehead (or automobile) torpedo, which when properly set and
ejected by compressed air propelled itself at a predetermined depth at a
speed of thirty knots an hour until it struck the object it was aimed at
or its compressed air power gave out.

The seven Holland boats built for the United States Navy, of which the
_Fulton_ is a prototype, carry five of these torpedoes, one in the tube
and two on either side of the hold, and each boat is also provided with
one compensating tank for each torpedo, so that when one or all are
fired their weight may be compensated by filling the tanks with water so
that the trim of the vessel will be kept the same and her stability
retained.

The _Fulton_, however, was bent on a peaceful errand, and carried dummy
torpedoes instead of the deadly engines of destruction that the
man-o'-war's man dreads.

"Dive thirty," ordered the captain, at the same time giving his wheel a
twist to direct the vessel's course according to the pointing finger of
the compass.

"Dive thirty, sir," repeated the steersman below, and with a slight
twist of his gear the horizontal rudders turned and the submarine
inclined downward; the level-indicator showed a slight slant and the
depth-gauge hand turned slowly round--twenty-two, twenty-five,
twenty-eight, then thirty feet, when the helmsman turned his wheel back
a little and the vessel forged ahead on a level keel.

At thirty feet below the surface the little craft, built like a cigar
on purpose to stand a tremendous squeeze, was subjected to a pressure of
2,160 pounds to the square fo