"Grace thinks she saw a big negro come on board," answered Dick. "We are trying to root him out."
The houseboat was searched from end to end, but nothing could be discovered of any intruder.
"Must have sneaked off again," said Sam. "If he did, I hope he didn't steal anything."
"We'll keep our eyes open after this," said Captain Starr.
The night passed quietly enough, but, for some reason she could not explain, Grace awoke long before the others. She tried to go to sleep again, but, finding that a failure, dressed and went out on the deck.
She had been out only a few minutes, when, on walking past the dining-room window, she saw a sight that filled her with amazement. By the closet was a burly negro, filling a carpetbag with silverware!
"Oh!" she cried. "Stop that!"
At the sound of her voice, the burly negro turned and scowled viciously at her.
"Yo' dun keep quiet!" he said in a low, intense voice.
"I shall not," answered Grace. "Help, somebody!" she called.
"Hush up, yo'!" fairly hissed the burly intruder, and sprang for the doorway. In another moment
