haft,
whence ladders still gave access to the lower galleries of the pit. The
engineer bent over the opening. Formerly from this place could be heard
the powerful whistle of the air inhaled by the ventilators. It was now a
silent abyss. It was like being at the mouth of some extinct volcano.

When the mine was being worked, ingenious machines were used in certain
shafts of the Aberfoyle colliery, which in this respect was very well
off; frames furnished with automatic lifts, working in wooden slides,
oscillating ladders, called "man-engines," which, by a simple movement,
permitted the miners to descend without danger.

But all these appliances had been carried away, after the cessation of
the works. In the Yarrow shaft there remained only a long succession
of ladders, separated at every fifty feet by narrow landings. Thirty of
these ladders placed thus end to end led the visitor down into the
lower gallery, a depth of fifteen hundred feet. This was the only way
of communication which existed between the bottom of the Dochart pit and
the open air. As to air, that came in by the Yarrow shaft, from whence
galleries communicated with another shaft whose orifice opened at a
higher level; the warm air naturally escaped by this species of inverted
siphon.

"I will follow you, my lad," said the engineer, signing to the young man
to precede him.

"As you please, Mr. Starr."

"Have you your lamp?"

"Yes, and I only wish it was still the safety lamp, which we formerly
had to use!"

"Sure enough," returned James Starr, "there is no fear of fire-damp
explosions now!"

Harry was provided with a simple oil lamp, the wick of which he lighted.
In the mine, now empty of coal, escapes of light carburetted hydrogen
could not occur. As no explosion need be feared, there was no necessity
for interposing between the flame and the surrounding air that metallic
screen which prevents the gas from catching fire. The Davy lamp was of
no use here. But if the danger did not exist, it was because the cause
of it had disappeared, and with this cause, the combustible in which
formerly consisted the riches of the Dochart pit.

Harry descended the first steps of the upper ladder. Starr followed.
They soon found themselves in a profound obscurity, which was only
relieved by the glimmer of the lamp. The young man held it above his
head, the better to light his companion. A dozen ladders were descended
by the engineer and his guide, with the m