Dodging the low trolley-wire which hung about five feet above the rails, we crawled across the coupling between two of the cars to the other side of the entry, and walked to the left, past the locomotive where the motorman was still sitting in his low seat, waiting to pull out his train of empty cars into the sudden darkness of the tunnel beyond. Then, for the first time, I learned that mines are echoless, and that sound—like light—is absorbed by the blotter-like walls of the tunnels.
We walked down the entry between the rails, and after a hundred yards turned with the switch in the track sharply to the right, and again on. Sense of direction or angles was lost, and, like the faces in a foreign race of people, where one can see little or no individuality, so here, each corner seemed the same, and in a hundred yards I was utterly lost. Above was the smooth, black roof; below, the ties and the rails; and on either side, behind the two long rows of props, the face of the coal-seam, which glittered and sparkled in the light from our pit-lamps like a dull diamond.
We talked a little. My companion asked me where I had worked before, how much I knew of mines, and a few other questions; and still we walked on, dodging the low wire that comes level with one’s ear, and stumbling over the layer of broken coal that lay strewn here and there between the rails.
The silence was like the darkness—a total absence of sound, rather than stillness, as my first impression of the mine had been that of an absence of light, rather than of darkness. The smoking lights in our caps seemed to press out through the blackness twenty feet around us, where the light disappeared and was gone. And always in front of us, out of the black darkness, the two long lines of props on either side of the track stepped one by one into the yellow haze of light and sank again into darkness behind us as we walked.
The air was cool and damp, but as we turned the last corner, the dampness seemed suddenly gone from it. It was warmer and closer. Here the track swerved up from one of the main tunnels into a 'room'; and at the end, or 'heading' of this room, which we reached a few minutes later, empty and waiting for its first load, stood one of the square cars which I had seen before at the mine-bottom and which we passed several times on sidings by the track. The car was pushed up to the end of the track and its wheels 'spragged' by two blocks of coal. Here the tunnel suddenly ended, and from the blank back 'face' a rough, broken pile of coal streamed down on both sides of the car and reared up before it against the roof.
'Just shovel 'er full, then wait till the motor takes her out and sends in an empty, and fill that one. I’ll look in on you once in a while and see how you’re getting along.'
Then he turned and walked down the track and left me in the dim light of my single pit-lamp.
II
In the first days of coal-mining—as in many mines to-day where modern methods have not superseded those of old-time miners—a man did all the work. With his hand-drill he bored into the face of the coal at the head of his room, or entry, and from his keg of powder he made long cartridges and inserted them into his drill-holes. Then, when the coal was blasted down, and he had broken it with a pick, he loaded it with his shovel into a car; and trimming square the face of the tunnel, propping when necessary, he pushed on and on until he broke through and joined the next tunnel or completed the required length of that single entry.
But to-day these conditions are, in most instances, changed. The work begins with the 'machine-men,' who operate the 'chain-machines.' In order that the blast may dislodge by gravity an even block of coal, of the dimensions of the cross-section of the tunnel, these men cut with their machines a 'sump-cut,' or, in other words, carve out an opening level with the floor, about six inches high and six feet deep, at the end of the tunnel. The machines—which are propelled by electricity—consist of a motor and a large oblong disk, about which travels an endless chain containing sharp steel 'bits' or picks. The machine is braced, the current turned on, and the disk advanced against the coal, automatically advancing as the bits grind out the coal. As soon as the machine has entered to the full six feet, the disk is withdrawn and the cut continued until it extends across the entire face.