The submarine, well down, now ran across the harbor at an angle, aiming to come up to the starboard of the second cruiser. Captain Nicholson explained his reason for doing this:
"I figure they will expect us on the side nearest the first cruiser," he said. "Therefore, I believe we stand a fair chance of surprising them by attacking on the starboard. At the same time, we will have our movements masked from the third and smaller cruiser by our second victim itself."
This sounded reasonable to the two lads, but they made no comment.
To foster an appearance of an attack off the second cruiser's port side, Captain Nicholson let go a decoy periscope to float with the tide's decided sweep to the left shore and draw the fire of the enemy in that direction.
Slowly the submarine advanced, and presently those on board could hear the unmistakable boom of heavy guns. The ruse had succeeded, and the cruisers and guns of the fort were aiming at the spot in the water where the decoy periscope led them to believe the submarine was floating.
The submarine rose so that the periscope took in the scene above the water. Captain Nicholson, glancing through the instrument, saw that he was at least 500 yards to the starboard of the second cruiser. Under full speed, the Y-3 ran straight up to her enemy's bow.
The periscope, protruding above the water, was quickly sighted by the cruiser, but before the vessel's guns could be brought to bear, Captain Nicholson released the second torpedo. Immediately the Y-3 dived again.
But before the submarine had entirely disappeared under the water, there came a loud roaring boom. The second torpedo had gone home.
"Magazine must have gone too," said Captain Nicholson briefly.
Frank and Jack glanced curiously at the members of the crew. Not at all nervous themselves, they were nevertheless surprised at the apparent coolness of the British sailors.