Underground mine

“ Underground surveys are calmly and efficiently made, huge mine charges deliberately and quietly placed, electrical connections carefully tested, and at the precise moment fired with terrific detonation and damage. ”

“ As the mines go deeper and further away from the opening they accumulate gas and underground water. The greatest number of injuries and deaths in the mines, and coal mining is among the most hazardous of all occupations, result from the falling of overhanging rock and coal; but the catastrophies which have shocked public opinion into a sympathetic attitude toward the commoners of the mines do not come from this steady death toll but have resulted from explosions or fires that have trapped and suffocated or burned their scores and hundreds. ”

“ When the men get out of the skip down in the mine, there are many different roads in it, and each man has to go to his own part to work. When he reaches his place he has to drill holes in the rock for the dynamite which breaks up the rock, and the loose stones are taken away along the roads to the lift and then up to the top. There it is stamped with great hammers into dust, and washed, until the gold-dust is separated from the rest. There are thousands of men, both underground and at the top, always at work at the mines. ”

“ It is well known that, under present methods of mining, from 10 to 75% of any given deposit of coal is left underground as props and supports, or as low-grade material, or in overlying beds broken up through mining the lower bed first. An average of 50% of the coal is thus wasted or rendered valueless, as it cannot be removed subsequently because of the caving or falling in of the roofs of abandoned galleries and the breaking up of the adjoining overlying beds, including coal, floor, and roof. ”

“ The descriptions of underground workings that have now been given have, of necessity, been very general in their character. It is impossible, in a limited space, to describe the various methods and modifications of methods which are in use. No two mines, even in the same district, are worked exactly alike. Sometimes they differ widely in plan and operation. That system must be employed in each one which will best meet its peculiar requirements. ”

“ In a few of the largest collieries it has been found advantageous to establish underground stationary engines, which bring the trains of waggons, by means of an endless rope, along the galleries to the bottom of the shaft. In other mines, such as those of Worsley in Lancashire, subterranean canals are cut, upon which the mineral is transported in boats.
In the European mines, the ores are usually lifted from the bottom of the shaft to the surface by steam-power, or horse-gins; but in Spanish America, men, and even women, are employed for this purpose. ”

“ Nothing so startles a mining community as to have this signal come from underground. It may mean death and disaster. It surely means that there are injured men to be brought up to the surface, and the time elapsing before their arrival is always filled with deepest anxiety.
[Pg 51]
It was so in the present case, and when the cage containing the two battered miners, one of whom had also every appearance of being dead, emerged from the shaft, a throng of spectators was waiting to greet it. ”

“ So long as they last these easily accessible alluvial deposits will always be cheaper to work than the deep mines. On the other hand, they may give out, and recent explorations underground seem to indicate that there is still much valuable ore not only of tin but of other metals too, to be obtained from the old mines of Cornwall. ”

“ On account of the large number of men, quantity of material, expense, etc., the use of mining operations is very carefully considered beforehand, and careful plans devised before starting on any underground operations. Attacks are sometimes undertaken only to demolish a portion of the hostile trenches, in view of a local operation. At other times they form a part of a large offensive movement. Generally speaking, speed and silence are the first requisites. If these can be obtained with any degree of certainty, mining operations are nearly always successful. ”

“ The sturdy, honest toilers of this city work on without the inspiration that prompts460 deeds of valor upon the field of battle. They do their duty because it is their duty. They have made Underground Butte even greater than the greatest mining camp on earth.”
For further illustration of the greatness of the mines of Butte I have in my possession the following statement from the Anaconda Company’s last year’s report. There were brought by rail to the smelters at Anaconda one million four hundred and fifty-nine thousand tons of ore from the Butte mines. ”

“ If one is in the mines without a light, he has before him, behind him, everywhere, utter blackness. To be lost in this way, a mile from any opening to day, in the midst of a confusion of galleries, in an abandoned mine, and to be compelled to feel one’s way to safety, is a painful experience, is one indeed which the writer himself has had.
There comes a time in the history of every mine when it is pervaded only by silence and darkness. All the coal that can be carried from it by the shaft or slope or other outlet has been mined and taken out, and the place is abandoned. ”

“ In drift-mining the rich gravel is covered by hard lava rock thrown up by some old volcanic outburst. Tunnels are driven by blasting with dynamite, or by drilling under the rock to reach the gravel which usually lies in the buried channel of an old river. The long drifts, or tunnels, needed are very expensive and only mine owners with capital can work these claims.
Richest of all are the quartz mines, where beautiful white rock, rich with sparkling gold, is found in veins, or "lodes," cropping out of hillsides or dipping down under the earth. ”

“ It is a waste of crushed pillars, fallen rock, and blocked passages. Indeed, it is difficult to conceive of anything more weird and desolate than an abandoned mine. To walk or climb or creep through one is like walking with Dante through the regions of the lost. There are masses of rock piled up in great confusion to the jagged roof, dull surfaces of [135] coal and slate, rotting timbers patched here and there with spots of snow-white fungus, black stretches of still water into which a bit of falling slate or coal will strike and send a thousand echoes rattling through the ghostly chambers. ”

“ A gold mine now consists of a shaft or pit dug several hundred feet down into the rock, with levels or galleries running off from it and with big openings like rooms made where the rock was dug out. The roofs of the rooms are supported by great timbers. To break away the rock, the miner makes a hole with a rock drill worked by electricity or compressed air, puts powder or dynamite into the hole and explodes it. The broken rock is then raised to the surface and crushed in a "stamping mill." Here the ore is fed into a great steel box called a "mortar." ”

“ When we have to use drainage tunnels for our mines we carry the water off from the mouth of the tunnel in a flume, placing quicksilver in the riffles, and if it is a copper mine we place scrap iron in the water and we also use the water for power to assist us in mining, so that at the present time we extract and reduce ore at a lower rate than in other parts of the world, for there is no wastefill management and no overproduction, for in all our mining operations we work those that cost the least, and we operate our coal mines in the same way. ”

“ The passages to the mines are so narrow, that persons can with difficulty pass each other; they then expand into high vaults, the roofs of which are ornamented with beautiful crystals of celestine and gypsum. On account of the excessive heat, the workmen labour in a nearly nude state, their dark brown skins sprinkled with light yellow sulphur dust, making them look savage and strange in the extreme. Towards the end of the last century, the sulphur mine of Sommatin caught fire, the conflagration causing the complete abandonment of the pit. ”

“ When the crater radius is equal to the line of least resistance, the mine is termed common; when this radius is greater than the line of least resistance, the mine is termed overcharged; and when the radius is less, undercharged. A mine of small dimensions, formed by sinking a shaft in the ground, is termed a fougasse. The term camouflet is applied to a mine used to suffocate the enemy's miner, without producing an explosion. Small mines made in rock or masonry, merely for the purpose of excavation, without any considerable external explosion, are called blasts. ”

“ In some of the dark and dusty chambers which open here the miner's pick is heard, and now and then the muffled report of the miner's blast comes echoing through the vaulted aisles.
"But this is not the station where we are intended to stop. Our car moves on, and we plunge through two hundred feet more of the rocky rind of the earth. Above us the mouth of the shaft seems narrowed into an insignificant hole; before us opens a dark street, over which, on a tramway, mules are hauling carloads of coal, which is starting on its way to the surface. Miners with picks are moving to and fro ”

“ The want of capitalists in the mine country, and of practical skill in the boring, blasting, sinking shafts and galleries, oppose obstacles to the [Pg 160] successful progress of mining. There is but one regular hearth-furnace for smelting in the whole district; and that is on the modern plan of English furnaces. There are not over four or five regular shafts in about forty mines; there is not an engine, either by horse, steam, or water power, for removing water from the mines, several of which have been abandoned on this account, with rich prospects of ore in view. ”

“ The method used in Mine 33 was what is known technically as “shooting off the solid,” that is, drilling a deep hole in the solid coal body and blasting it down very much as rock is blasted in railroad building operations. This method, while it procures the greatest amount of coal with the least expenditure of labor, is at the same time very expensive to the miner who must buy his powder and in addition to his regular blacksmith tax must pay for the sharpening of all the drill bits.
It is in these blasting operations that so many men in soft-coal mines lose their lives. ”

“ The machinery used for crushing the rock is set in motion by these streams. On every side the men, women, and children employed on the works are seen moving about in all directions, like a busy colony of ants. The ore is obtained without much difficulty.
A tunnel has been formed at the bottom of the mine through which the waters flow after they have performed their task, which also carries away the crushed granite, while the heavier metalliferous substances are precipitated into the troughs. ”

“ Since the first discovery of lead in this Territory, the number of mines has been much increased, and hardly a season passes without some new discovery. Every discovery of importance soon becomes the centre of mining attraction. As the ore is found in the diluvial soil, it is generally exhausted on reaching the solid rock; and after penetrating a considerable area of the surface with any, or but partial success, the locality is abandoned, and a new one sought. As the mines are worked without capital, and the ore is dispersed over a wide area, the number of localities is almost indefinite. ”

“ There are extensive coal mines about eight miles from us. Some of them are very deep under-ground, but others are not, but the coal is brought up a slope in wagons on wheels. I was up last winter, and saw the men and boys that work in the mines. They were terribly black with coal dust. Each of them carries a safety-lamp, which gives but a feeble light in such dark places. I was up two winters ago, and saw one of the places for myself. At one of the largest mines, about two years ago, there was an explosion, which killed forty men, and ruined the mine. ”

“ Upon the bed-rock is a deposit, from three to four feet in depth, of gravel and boulders, in which the gold is hidden. This is called by the miners "pay-dirt," and to remove it to the surface and wash it is the end of mining. It is an expensive and laborious process indeed. The water has first to be controlled; and in mines of not too great depth this is done by a drain ditch along the bed-rock, commenced many claims below. In this all the claim-holders are interested, and all contribute their quota of the labor and expense of digging it. ”

“ More than fifteen thousand men find employment in this weird city. Day after day the brave miners go down into the mines, never sure that they will see the sunlight again, for many are the perils of mining. Who has not read of the terrible disasters caused by suffocation from fire damp, by flood, the falling of walls, or the explosion of coal dust? Small particles of coal dust are constantly floating in the mines, and much is stirred up by the cars used to carry the coal to the outside world. ”

“ A similar sacrifice in the shape of pillars is often necessary to support the surface, either to avoid injury to valuable structures or to prevent a flooding of the mine. As already noted large pillars must always be left to protect shafts, adits and the more important mine-passages necessary for drainage, ventilation and the haulage of mineral. In the early history of mining there was but little attempt at systematic development and working, and the mines were often irregular and tortuous. ”