."

He soon obtained a glow in the tinder, lit a match, and set a candle
burning. Then taking each one of the small mining-picks, the two lads
descended into the solitary place, Dummy bearing the light and beginning
to run along cheerily, as if familiarity with the long wandering
passages and gloomy chambers had made them pleasant and home-like. Mark
followed him briskly enough, for the solemn silence of the place was
familiar enough to him, and he looked upon it merely as a great burrow,
which had no terrors whether the men were at work or no.

Dummy went steadily on, taking the shortest way to the chamber where he
had shown his companion that it was no _cul de sac_, but the entrance to
the grotto where nature had effected all the mining, and at last the
great abyss where the sound of the falling water filled the air was
reached. Here Dummy seated himself, with his legs swinging over the
edge, and looked down.

"That's where the river water comes in," he said, "through a big crack.
Now let's see where it goes, because it must go somewhere."

"Right into the middle of the earth, perhaps," said Mark, gazing down
into the awful gulf, and listening to the rushing sound.

"Nay," said Dummy; "water don't go down into the earth without coming
out again somewhere. Dessay if we keep on we shall come out to
daylight."

"Eh?" cried Mark; "then we had better find it and stop it up, for as I
said the other day, we don't want any one to find a back way into our
mine."

"That's what I thought, Master Mark," said Dummy quietly. "Wouldn't do
for Purlrose and his men to find it, and come in some day, would it?"

"No; that wouldn't do at all, Dummy."

"No, sir. But how's your head?"

"My head? Oh, I'd forgotten all about it."

"I know'd you would," said the lad, grinning. "Don't feel so tired,
neither?"

"No."

"Then I'll light another candle, and we'll get on: but don't you get
slipping while we are going round here, because I don't know how deep it
is, and I mightn't be able to get you out."

"You take care of yourself, and lead on," said Mark shortly. "I dare
say I can go where you do."

Dummy nodded, and after handing the second candle to his master, he went
along sidewise, and then lowered himself over the edge of the gulf, and
dropped out of sight.

"Only 'bout a fathom, Master Mark," he shouted, "and plenty of room."

Mark did not hesitate, but lowered himself in turn, and dropped upon his
feet, to