GENERAL VIEW OF MINING OPERATIONS.
The principle of long-wall working (Shropshire and Derbyshire method) is the extraction of all the available coal by the single process of first working, maintaining the roads by means of stone-walls or wooden props. This system is applicable with advantage only to thin seams which lie near to the surface, and in which the workings may be of a very limited extent.
TOOLS USED BY MINERS IN CORNWALL.
a. Pick. b. Gad. c. Shovel. d. Mallet. e. Borer. f. Claying-bar. g. Needle or nail. h. Scraper. i. Tamping-bar.
According to the various hardness of the minerals or of the rocks in which they are embedded, different means and implements for dividing the masses are employed. In loose earth, sand, and clay, shovels and scrapers suffice; in gypsum, coal, and rock-salt, the pick becomes necessary; in many hard slates, gads must be driven into the small openings made with the point of the pick. In still harder stones, forming the great majority of those which occur in veins and strata, recourse must be had to the explosive power of gunpowder, which is also largely employed in our coal-mines. The tools used for this purpose are the borer, an iron bar tipped with steel, formed like a thick chisel, which is held by one man straight in the hole with constant rotation on its axis, while another strikes the head of it with the iron sledge or mallet; the scraper for clearing out the hole from time to time; the claying-bar, a tapering iron rod, which, after the introduction of some tenacious clay into the cavity, is forced into it with great violence, and, condensing the clay into all the crevices of the rock, secures the dryness of the hole; and the nail, a small taper rod of copper, which, after the charge has been introduced, is inserted to reach the bottom of the hole, which is now ready for tamping. For this purpose, any soft species of rock free from flinty particles, which might provoke a premature explosion, is introduced in small quantities at a time, and rammed very hard by the tamping bar, which is held steadily by one man and struck with a sledge by another. The hole being thus filled, the nail is withdrawn by putting a bar through its eye and striking it upwards. Thus a small perforation or vent is left for the safety fuse, a woven cylinder containing gunpowder, and protected by a coating of tar. The fire being applied, the men retire to a safe distance.
Often, in order to lose as little time as possible, a number of shots are fired together, so that the explosions, pouring out their tongues of flame in rapid succession, and awakening the subterranean echoes far and wide, afford a highly interesting spectacle. But woe to the miner if he be too hasty to return to his post, for it often happens that a treacherous shot goes off several minutes after being lighted, and, exploding in the face of the imprudent workman, disfigures him for life, or kills him on the spot.
Accidents in blasting arise also from other causes, such as a negligent handling of the powder while preparing the charge, or some delay in retiring after the fuse has been kindled. It was an incident of the latter kind which some years back called forth the following instance of heroism.
‘In a certain Cornish mine,’ says Thomas Carlyle,[[36]] ‘two miners, deep down in the shaft, were engaged in putting in a shot for blasting; they had completed their affair, and were about to give the signal for being hoisted up. One at a time was all their coadjutor at the top could manage, and the second was to kindle the match and then mount with all speed. Now it chanced, while they were still below, one of them thought the match too long, tried to break it shorter, took a couple of stones, a flat and a sharp, to cut it shorter, did cut it off the due length, but, horrible to relate, kindled it at the same time, and both were still below. Both shouted vehemently to the coadjutor at the windlass, both sprang at the basket; the windlass-man could not move it with them both. Here was a moment for poor miner Jack and miner Will! Instant horrible death hangs over both, when Will generously resigns himself. “Go aloft, Jack, and sit down. Away! In one minute I shall be in heaven!” Jack bounds aloft, the explosion instantly follows, bruises his face as he looks over; he is safe above ground; and poor Will? Descending eagerly, they find poor Will, too, as if by miracle, buried under rocks which had arched themselves over him, and little injured; he too is brought up safe; and all ends joyfully, say the newspapers, which have duly specified the event.
‘Such a piece of manly promptitude and salutary human heroism was worth investigating. It was investigated and found to be accurate to the letter, with this addition and explanation, that Will Verran, an honest, ignorant, good man, entirely given up to Methodism, had been perfect in the “faith of assurance;” certain that he should get to heaven if he died, certain that Jack Roberts would not, which had been the ground of his decision in that great moment; for the rest that he much wished to learn reading and writing, and find some way of life above ground instead of below. By aid of the Misses Fox and the rest of that family, a subscription (modest Anti-Hudson Testimonial) was raised for this Methodist hero; he emerged into daylight with fifty pounds in his pocket; did strenuously try, for certain months, to learn reading and writing; found he could not learn those arts, or either of them; took his money and bought cows with it, wedding at the same time some likely milkmaid.’