"Quick! Open the man hole cover!" said Amos Henderson.

Washington threw back the lever cams, and in rushed the fresh air. It was a blessed relief from the terrible oppressiveness of the foul atmosphere of the boat. They all breathed deeply, and, in a few minutes the effects of their long imprisonment had passed off.

They went out on the small deck. It was getting dusk, and the reflection of the red sunset shone brightly on the heaving water.

"I 'spected I'd neber see dis again," said Washington. "Thought suah I was a gone chicken!"

"We had a most fortunate escape," said the professor. "You did the trick for us when you let the acid run from that tank into the sea. It mingled with the water and burned or ate through the stems of the grass so they no longer held the ship. I saw what had happened as soon as I looked out of the bull's-eye, and that's why I had you turn out all the acid you could. It was just as if liquid fire had touched the sea weed and burnt it off."

"Golly!" exclaimed Washington. "Fust I know I'll be a perfessor myself!"

Supper was eaten with the ship on the surface of the ocean, for it was impossible to go below until the leak in the air tanks had been repaired. Work was begun on this the next day, and though it proved a difficult job it was accomplished by Mr. Henderson and the boys.

There were several minor repairs to be made to the machinery, and it was a week before all was in readiness for another descent beneath the waves. In the meanwhile the craft had moved slowly southward on the surface, where no very great speed was possible.

Toward evening, on the seventh day after their adventure with the Sargasso Sea, the travelers closed the man hole, and with air tanks well filled slowly sank beneath the waves. Supper was eaten at a depth of sixty feet, and after the meal, while Washington was washing the dishes, the others sat and looked out through the bull's-eyes at the big fishes which floated past.

"I wouldn't like to catch one of them air things on my hook an' line," observed Bill, as a particularly large fish went past. "I reckon I'd have trouble landin' him."