How deep and large the tunnel or drift might be, the boys could judge only by the size of the dump, for a heavy door prevented entrance. From under the door trickled a stream of clear cold water, which had already proved a great convenience. The Aurora mine, a hundred yards below, was almost precisely similar in outward appearance—even to the rivulet, but it had no door.

Breakfast dispatched and overalls donned, their picks sharpened, their lamps “trimmed and burning,” the firm marched up to the portal in single file, Max at the head.

“Open, sesame!” shouted the leader.

“Allee samee open,” echoed Len, in the best Chinese he knew.

“Kai duxon parasitidos gignotai,” muttered McKinnon in broad Gaelic Greek.

But his talisman was no more effective than that of the others, and the door stood firm.

Max struck an attitude resembling Thor with his hammer, and made ready to deal the barricade a splintering blow.

“He that would eat the kernel maun crack the nut,” pronounced Sandy, in as solemn a tone of voice as though he were giving a death-warrant.

“Hold on!” exclaimed Len, seizing his partner’s uplifted arm. “Don’t smash it. I reckon we can get in more peaceably. Let’s try to pry off the lock.”

“Very well,” assented Max; “here goes!”