But he was mistaken, for the killer, after coming a little distance after the whale, suddenly turned, hesitated for a moment, and then disappeared in the depths of the ocean.

The whale, however, continued to come on, speeding through the water with powerful strokes. There was an uneasy movement among some of the passengers.

“Suppose he strikes the ship,” suggested one woman.

“Nonsense! He couldn’t,” said her husband.

“The old man had better get under way, just the same,” remarked a sailor near Tom, as he looked up at the bridge where the captain was standing.

The “old man,” or commander, evidently thought the same thing, for, after a glance at the oncoming leviathan, which was still headed directly for the vessel, he shoved the lever of the telegraph signal over to “full speed ahead.”

Hardly had he done so than the whale sank from sight.

“Oh, I’m so glad!” exclaimed the woman who had first spoken of the possibility of the whale hitting the ship, “I am afraid of those terrible creatures.”

“They’re as harmless as a cow, unless they get angry,” said her husband.

Slowly the great ship began to move through the water. Tom and his friends were about to go back to their cabin, for they thought the excitement over, when, as the young inventor turned from the rail, he felt a vibration throughout the whole length of the steamer, as if it had hit on a sand-bar.