The steamer was now getting well down toward the Mona Passage, and on the day following land was sighted in the distance, a series of somewhat barren rocks. A heavy wind was blowing.

“Now we are going to pass through the monkey,” said Darry, after a talk with the professor.

“Pass through the monkey?” repeated Frank. “Is this another of your little jokes, Darry?”

“Not at all. Mona means monkey, so the professor told me.”

“Will we stop?”

“No, we won’t go anywhere near land. The next steamer stops, I believe, but not this one.”

“I wouldn’t mind spending some time in Porto Rico and Cuba,” put in Mark. “There must have been great excitement during the war with Spain.”

“Perhaps we’ll stop there on our way home,” said Sam. “I should like to visit Havana.”

The Mona Passage, or Strait, passed, the course of the steamer was changed to the south-westward. They were now in the Caribbean Sea, but the waters looked very much as they had on the bosom of the Atlantic. The wind increased until the blow promised to be an unusually severe one.

“My, but this wind is a corker!” ejaculated Frank, as he and Mark tried in vain to walk the open deck. “Perhaps we are going to have a hurricane.”