the other to a ring-bolt in the massive rudder, the officer turned with a sigh and walked away.
On the following morning the Spanish spy, weary and cramped with his long vigil, was amazed to see an utter stranger emerge cautiously from beneath the wharf he had been watching, and walk quickly away. For a moment the spy was undecided as to whether he should follow this person or seek to discover where he had come from. Then choosing the former course, he followed Professor Rivers at a respectful distance, until he had the vast satisfaction of seeing him meet, near the custom-house, the captain of the tug that was avowedly bound for Havana.
There was a connection then between those who hid beneath the wharf and the suspected tow anchored in the harbour. Undoubtedly a store of contraband goods was concealed under the wharf, and an effort would be made to convey them on board the tug before she sailed. What a reward was in prospect for him could he but discover it!
A little later the spy, with two companions, all armed, occupied a skiff that made its way cautiously through the dark spaces beneath the wharf he had watched so long. Suddenly between them and the outer daylight two men appeared one after the other. Both slid down one of the piles supporting the pier and dropped into the water, or at least the exulting spy thought they did so as he hastily urged his boat in that direction.
To his amazement and disgust, when he reached the spot where they had disappeared, he could discover no trace of them. Neither was there a boat or a hiding-place into which they could have gone. The man was furious at being thus baffled, and uttered many a fierce Spanish oath. Finally, convinced that further search in that direction was fruitless, he pulled out into the harbour to watch the mysterious tow that still lay at anchor. As