"Probably a tin can," said Betty.
"No," spoke Mollie, resolutely.
"Here, let me help you!" exclaimed Amy.
She looked about for something with which to dig. Near where Mollie had uncovered the piece of metal a queerly shaped stick stuck upright in the sand. Amy pulled it out, with no small effort, and at once began digging.
"Oh, it's some sort of a box—an iron box!" cried Mollie, with eager, shining eyes. "We have really found something."
Mollie and Amy dug until they had wholly uncovered the object. Then, with a quick motion, Mollie put her hands under the lower edges, and with a sudden effort brought up out of the hole in the sand a curious iron box.
"It—it really is—something!" she said.
Instinctively Betty looked out over the bay in the direction taken by the strange, quarreling men in the motor boat.