"Now, was this tunnel constructed on purpose to reach this spring?" asked Harry.
The lads examined the walls minutely, but there was no opening from the chamber, save the one by which they had entered.
"This must have been the milk house," laughed Frank, always ready to turn any subject under discussion into a joke. "I wonder if they kept their cows on the top of the peak? If they had tied their tails together and put one over each side, they never could have run away."
On their way back to Chamber B the boys discovered an opening in the north wall of the tunnel. This led to another tunnel, running in a northwesterly direction for about one hundred feet and ending in a chamber larger than any of the others. Nestor caught sight of a sparkle on the walls as he swung the flashlight about and pointed glittering sections out to the boys.
"Gold!" cried Frank.
"I'll bet a cooky we've found the hidden mine!" cried Jimmie.
"It is gold, all right," Harry Stevens said, "but there's no knowing whether it is here in quantities sufficient to pay the expense of mining and crushing the ore."
"Huh!" cried Jimmie, in a tone of reproach. "Don't you know that rock that will produce a dollar a tone is worth working? Well, then, look at this! There's ten dollars worth in the spot I cover with my hand! We've found somethin', boys!"
"So it wasn't to escape their enemies that the old chaps sequestered themselves here," said Fenton. "It was to dig out gold!"
"I never heard that there was gold in this part of Mexico," observed Jack. "I reckon we'll wake up when we get out into the sunlight."