were rather surprised to find that it was the glass windows, or prisms, that revolved by means of the clockwork, and not the lantern itself. If the lantern went around it could not be trimmed without being stopped, and this would make a difference in the flashes, Lucy explained, and so confuse the sailors.
At certain places in the glass sides of the lantern room, there were blank spaces where no light could flash out, and this gave the proper signal for that part of the coast.
If you will take a pasteboard tube, such as calenders are mailed in, cut two or three holes near the top, making the holes the same distance apart, with blank spaces in between, and set this tube over a candle, you will have a good idea of a lighthouse. Then if you will turn the tube around, with the lighted candle still inside, you will get the effect of a flashing light, such as Bob and his chums were shown.
They were much interested, and stayed in the tower some time, watching Mr. Floyd trim and fill the lamp, to keep it bright.
"This is certainly great!" exclaimed Frank, when they were ready to leave."
"It sure is," agreed Sammy. Then he was unable to restrain his curiosity in spite of what he had agreed with his chums. "Say," he asked earnestly, when they were down in the living-room again, "did you ever hear anything of the pirate gold buried around here, Mr. Floyd?"
The light-keeper laughed.
"Oh, yes, I've heard," he said, "but I don't take any stock in it."
Sammy was not discouraged by this answer.
"Did you ever dig for it?" he persisted.
"Oh, yes, when I first came here, and heard the story, I was young and foolish, and I had my try at it," answered the
