Fire Damp.An opportunity presented itself several years after my examination of Vesuvius of witnessing another form under which fire occasionally exerts its formidable power.I was visiting a friend37at Merthyr Tydfil, who possessed very extensive coal-mines. I inquired of my host whether any fire-damp existed in them. On receiving an affirmative answer, I expressed a wish to become personally acquainted with the miner’s invisible but most dangerous enemy. Arrangements were therefore made for my visit to the subterranean world on the following day. Professor Moll of Utrecht, who was also a guest, expressed a wish to accompany me.37The late Sir John J. Guest, Bart.The entrance to the mine is situated in the side of a mountain. Its chief manager conducted our expedition to visit the ‘fire-king.’We found a coal-waggon drawn by a horse, and filled with clean straw, standing on the railway which led into the workings.The manager, Professor Moll, and myself, together with two or three assistants, with candles, lanterns, and Davy-lamps, got into this vehicle, which immediately entered the adit of the mine. We advanced at a good pace, passing at intervals doors which opened on our approach and then instantly closed. Each door had an attendant boy, whose duty was confined to the regulation of his own door.{226}Many were the doors we passed before we arrived at the termination of the tram-road. After travelling about a mile and a half, our carriage stopped and we alighted. We now proceeded on foot, each carrying his own candle, until we reached a kind of chamber where one of our attendants was left with the candles.〈DRIVE INTO THE MOUNTAIN.〉We, each holding a Davy-lamp in our hand, advanced towards a small opening in the side of this chamber, which was so low that we were compelled to crawl, one after another, on our hands and knees. A powerful current of air rushed through this small passage. On reaching the end of it, we found ourselves in a much larger chamber from which the coal had been excavated. At a little distance opposite to the path by which we entered was a continuation of the same narrow hole which had led us to the waste in which we now stood. From this opening issued the powerful stream of air which seemed to pass in a direct course from one opening to the other.On our right hand the large chamber we had entered appeared to spread to a very considerable distance, its termination being lost in darkness. The floor was covered with fragments which had fallen from the roof; so that, besides the risk from explosion, there was also a minor one arising from the possible fall of some huge mass of slate from the roof of the excavation beneath which we stood: an accident which I had already witnessed in the waste of another coal-mine. As we advanced over this flaky flooring it was evident that we were making a considerable ascent. We, in fact, now occupied a vast cavern, which had been originally formed by the extraction of the coal, and then partially filled up by the falling in from time to time of portions of the slaty roof.〈TEMPLE OF THE FIRE-KING.〉As we advanced cautiously with our Davy-lamps beyond{227}the current of air which had hitherto accompanied us, it was evident that a change had taken place in their light: for the flames became much enlarged. Professor Moll and myself mounted a huge heap of these fragments, and thus came into contact with air highly charged with carburetted hydrogen. At this point there was a very sensible difference in the atmosphere, even by a change of three feet in the elevation of the lamp.Holding up the lamp at the level of my head, I could not see the wick of the lamp, but a general flame seemed to fill the inside of its wire-covering. On lowering it to the height of my knee, the wick resumed its large nebulous appearance.My companion, Professor Moll, was very much delighted with this experiment. He told me he had often at his lectures explained these effects to his pupils, but that this was the first exhibition of them he had ever witnessed in their natural home.Although well acquainted with the miniature explosions of the experimentalist, I found it very difficult to realize in my own mind the effects which might result from an explosion under the circumstances in which we were then placed. I inquired of the manager, who stood by my side, what would probably be the effect, if an explosion were to take place? Pointing to the vast heap of shale from which I had just descended, he said the whole of that would be blown through the narrow channel by which we entered, and every door we had passed through would be blown down.We now retraced our steps, and crawling back through the narrow passage, rejoined our carriage, and were rapidly conveyed to the light of day.
An opportunity presented itself several years after my examination of Vesuvius of witnessing another form under which fire occasionally exerts its formidable power.
I was visiting a friend37at Merthyr Tydfil, who possessed very extensive coal-mines. I inquired of my host whether any fire-damp existed in them. On receiving an affirmative answer, I expressed a wish to become personally acquainted with the miner’s invisible but most dangerous enemy. Arrangements were therefore made for my visit to the subterranean world on the following day. Professor Moll of Utrecht, who was also a guest, expressed a wish to accompany me.
37The late Sir John J. Guest, Bart.
37The late Sir John J. Guest, Bart.
The entrance to the mine is situated in the side of a mountain. Its chief manager conducted our expedition to visit the ‘fire-king.’
We found a coal-waggon drawn by a horse, and filled with clean straw, standing on the railway which led into the workings.
The manager, Professor Moll, and myself, together with two or three assistants, with candles, lanterns, and Davy-lamps, got into this vehicle, which immediately entered the adit of the mine. We advanced at a good pace, passing at intervals doors which opened on our approach and then instantly closed. Each door had an attendant boy, whose duty was confined to the regulation of his own door.{226}
Many were the doors we passed before we arrived at the termination of the tram-road. After travelling about a mile and a half, our carriage stopped and we alighted. We now proceeded on foot, each carrying his own candle, until we reached a kind of chamber where one of our attendants was left with the candles.
〈DRIVE INTO THE MOUNTAIN.〉
We, each holding a Davy-lamp in our hand, advanced towards a small opening in the side of this chamber, which was so low that we were compelled to crawl, one after another, on our hands and knees. A powerful current of air rushed through this small passage. On reaching the end of it, we found ourselves in a much larger chamber from which the coal had been excavated. At a little distance opposite to the path by which we entered was a continuation of the same narrow hole which had led us to the waste in which we now stood. From this opening issued the powerful stream of air which seemed to pass in a direct course from one opening to the other.
On our right hand the large chamber we had entered appeared to spread to a very considerable distance, its termination being lost in darkness. The floor was covered with fragments which had fallen from the roof; so that, besides the risk from explosion, there was also a minor one arising from the possible fall of some huge mass of slate from the roof of the excavation beneath which we stood: an accident which I had already witnessed in the waste of another coal-mine. As we advanced over this flaky flooring it was evident that we were making a considerable ascent. We, in fact, now occupied a vast cavern, which had been originally formed by the extraction of the coal, and then partially filled up by the falling in from time to time of portions of the slaty roof.
〈TEMPLE OF THE FIRE-KING.〉
As we advanced cautiously with our Davy-lamps beyond{227}the current of air which had hitherto accompanied us, it was evident that a change had taken place in their light: for the flames became much enlarged. Professor Moll and myself mounted a huge heap of these fragments, and thus came into contact with air highly charged with carburetted hydrogen. At this point there was a very sensible difference in the atmosphere, even by a change of three feet in the elevation of the lamp.
Holding up the lamp at the level of my head, I could not see the wick of the lamp, but a general flame seemed to fill the inside of its wire-covering. On lowering it to the height of my knee, the wick resumed its large nebulous appearance.
My companion, Professor Moll, was very much delighted with this experiment. He told me he had often at his lectures explained these effects to his pupils, but that this was the first exhibition of them he had ever witnessed in their natural home.
Although well acquainted with the miniature explosions of the experimentalist, I found it very difficult to realize in my own mind the effects which might result from an explosion under the circumstances in which we were then placed. I inquired of the manager, who stood by my side, what would probably be the effect, if an explosion were to take place? Pointing to the vast heap of shale from which I had just descended, he said the whole of that would be blown through the narrow channel by which we entered, and every door we had passed through would be blown down.
We now retraced our steps, and crawling back through the narrow passage, rejoined our carriage, and were rapidly conveyed to the light of day.