But as it actually happened, the sand bar upon which the tug had driven lay some distance beneath the surface. And it had caught the vessel by the keel.
The engines throbbed wildly, doing their noblest to pull the vessel off; and then one after another came the great waves, tossing her this way and that, wrenching and twisting, lifting and lifting again, while every one on deck clung for his life.
There was a minute or two of agonizing suspense, while the shore batteries kept up a galling fire and the merchantman steamed out to sea, proud of her triumph.
And then suddenly came a wild cheer from the imperiled Americans. Then men fairly shrieked in a transport of delight.
"She's moving! She's started! She's safe!"
And the men fairly hugged each other for joy. Slowly, then faster, then faster still, and finally at full speed backward. The gallant tug had torn herself loose from the grip of the sand—and was free!
The baffled Spanish batteries redoubled their fire at that. One could almost imagine the gunners grinding their teeth with rage as they saw their prey escaping.
But grinding their teeth did not seem to sharpen their eyes. Their aim was as bad as ever, and the Uncas seemed like the proverbial man in the rainstorm who keeps dry by "dodging the drops."
The confusion on board of the "escaped" vessel may be imagined. How that triumphant captain must have sworn Spanish oaths.
It was a ticklish task that Lieutenant Raymond had before him then. He knew there were sand bars about. But he did not know where they were. And the task was to avoid them.