The most indifferent person would have been touched at the appearance this deserted spot presented. It was like the skeleton of something that had formerly lived. A few wretched trees bordered a plain where the ground was hidden under the black dust of the mineral fuel, but no cinders nor even fragments of coal were to be seen. All had been carried away and consumed long ago.
They walked into the shed which covered the opening of the Yarrow shaft, 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.