“I thought they might have determined to try a little raid when I saw all that smoke,” said Lord Hastings. “We’ll stop her, at any rate.”

He took Frank’s place at the periscope and then commanded:

“Ten knots ahead, Mr. Templeton, and prepare for action!”

Jack jumped to obey this order, and a moment later the D-16 was in fighting trim. The engines throbbed and fussed, the water parted before the sharp prow of the vessel with an angry hiss, and the men stood at their posts.

The signal board flashed its first command, in letters of fire.

“No. 1 torpedo!”

The gunner was ready, and the second command—“attention”—was scarcely necessary.

Now, through the periscope, Lord Hastings gauged the range, and the signal board showed:

“Submerge!”

Almost at the same moment a second command showed plainly.