At about five o'clock in the afternoon the work of securing ballast was completed. The captain then announced that there was some work still to do in the hold. They would make their real start with daylight.
Dave and Bob were taking a last swim in the cool of the day. A clear sky and a fine breeze made the exercise delightful. Finally they got daring one another. Dave swam to the little sand islet next to the large one. Bob beat him in a race to the third of the group.
"Come on, if you've got the nerve," hailed Dave, making a quarter-mile dash for a sand mound still beyond them.
Bob started, but turned back. Dave made port and threw himself on the dry sand to rest. He got back his breath and sat up ready to take the home course, when his eye was attracted to something on an island about a furlong beyond the one he was on.
This was the nearest of the wooded islands. Dave had not noticed it much before. What made him notice it now was that, half-hidden in a great growth of bushes and vines, he noticed a small log hut.
In front of this a mast ran up into the air. At the moment that Dave looked he saw a man fumbling at the lines along this mast. It was to raise a blue bunting.
"Hello, hello," murmured Dave slowly, staring hard and thinking desperately fast. "Why, that's easy to guess. That man is Schmitt-Schmitt."
Dave could not precisely recognize the man at such a distance, but felt sure that it was Schmitt-Schmitt. He thought this the more positively as he saw that piece of blue bunting run up the mast.
"That was one of the signals I heard Schmitt-Schmitt tell the pilot about," mused Dave. "Red for provisions, blue for sickness or help wanted. Lantern at night, bunting by day. That's it, sure. He is signaling the pilot. That island is Schmitt-Schmitt's place of hiding. Say, here's something to think about."
Dave did not stay long to think about it. His eyes brightened and he seemed moved by some inspiriting idea as he jumped into the water and was soon back in the company of his chum, Bob Vilett.