CHAPTER VI. SIMON FORD'S EXPERIMENT
THE old clock in the cottage struck one as James Starr and his twocompanions went out. A dim light penetrated through the ventilatingshaft into the glade. Harry's lamp was not necessary here, but itwould very soon be of use, for the old overman was about to conduct theengineer to the very end of the Dochart pit.
After following the principal gallery for a distance of two miles,the three explorers--for, as will be seen, this was a regularexploration--arrived at the entrance of a narrow tunnel. It was like anave, the roof of which rested on woodwork, covered with white moss. Itfollowed very nearly the line traced by the course of the river Forth,fifteen hundred feet above.
"So we are going to the end of the last vein?" said James Starr.
"Ay! You know the mine well still."
"Well, Simon," returned the engineer, "it will be difficult to gofurther than that, if I don't mistake."
"Yes, indeed, Mr. Starr. That was where our picks tore out the last bitof coal in the seam. I remember it as if it were yesterday. I myselfgave that last blow, and it re-echoed in my heart more dismally than onthe rock. Only sandstone and schist were round us after that, and whenthe truck rolled towards the shaft, I followed, with my heart as full asthough it were a funeral. It seemed to me that the soul of the mine wasgoing with it."
The gravity with which the old man uttered these words impressed theengineer, who was not far from sharing his sentiments. They were thoseof the sailor who leaves his disabled vessel--of the proprietor who seesthe house of his ancestors pulled down. He pressed Ford's hand; but nowthe latter seized that of the engineer, and, wringing it:
"That day we were all of us mistaken," he exclaimed. "No! The old minewas not dead. It was not a corpse that the miners abandoned; and I dareto assert, Mr. Starr, that its heart beats still."
"Speak, Ford! Have you discovered a new vein?" cried the engineer,unable to contain himself. "I know you have! Your letter could meannothing else."
"Mr. Starr," said Simon Ford, "I did not wish to tell any man butyourself."
"And you did quite right, Ford. But tell me how, by what signs, are yousure?"
"Listen, sir!" resumed Simon. "It is not a seam that I have found."
"What is it, then?"
"Only positive proof that such a seam exists."
"And the proof?"
"Could fire-damp issue from the bowels of the earth if coal was notthere to produce it?"
"No, certainly not!" replied the engineer. "No coal, no fire-damp. Noeffects without a cause."
"Just as no smoke without fire."
"And have you recognized the presence of light carburetted hydrogen?"
"An old miner could not be deceived," answered Ford. "I have met withour old enemy, the fire-damp!"
"But suppose it was another gas," said Starr. "Firedamp is almostwithout smell, and colorless. It only really betrays its presence by anexplosion."
"Mr. Starr," said Simon Ford, "will you let me tell you what I havedone? Harry had once or twice observed something remarkable in hisexcursions to the west end of the mine. Fire, which suddenly went out,sometimes appeared along the face of the rock or on the embankment ofthe further galleries. How those flames were lighted, I could not andcannot say. But they were evidently owing to the presence of fire-damp,and to me fire-damp means a vein of coal."
"Did not these fires cause any explosion?" asked the engineer quickly.
"Yes, little partial explosions," replied Ford, "such as I used to causemyself when I wished to ascertain the presence of fire-damp. Do youremember how formerly it was the custom to try to prevent explosionsbefore our good genius, Humphry Davy, invented his safety-lamp?"
"Yes," replied James Starr. "You mean what the 'monk,' as the men calledhim, used to do. But I have never seen him in the exercise of his duty."
"Indeed, Mr. Starr, you are too young, in spite of your five-and-fiftyyears, to have seen that. But I, ten years older, often saw the last'monk' working in the mine. He was called so because he wore a long robelike a monk. His proper name was the 'fireman.' At that time there wasno other means of destroying the bad gas but by dispersing it in littleexplosions, before its buoyancy had collected it in too great quantitiesin the heights of the galleries. The monk, as we called him, with hisface masked, his head muffled up, all his body tightly wrapped in athick felt cloak, crawled along the ground. He could breathe down there,when the air was pure; and with his right hand he waved above his heada blazing torch. When the firedamp had accumulated in the air, so as toform a detonating mixture, the explosion occurred without being fatal,and, by often renewing this operation, catastrophes were prevented.Sometimes the 'monk' was injured or killed in his work, then anothertook his place. This was done in all mines until the Davy lamp wasuniversally adopted. But I knew the plan, and by its means I discoveredthe presence of firedamp and consequently that of a new seam of coal inthe Dochart pit."
All that the old overman had related of the so-called "monk" or"fireman" was perfectly true. The air in the galleries of mines wasformerly always purified in the way described.
Fire-damp, marsh-gas, or carburetted hydrogen, is colorless, almostscentless; it burns with a blue flame, and makes respiration impossible.The miner could not live in a place filled with this injurious gas, anymore than one could live in a gasometer full of common gas. Moreover,fire-damp, as well as the latter, a mixture of inflammable gases, formsa detonating mixture as soon as the air unites with it in a proportionof eight, and perhaps even five to the hundred. When this mixture islighted by any cause, there is an explosion, almost always followed by afrightful catastrophe.
As they walked on, Simon Ford told the engineer all that he had doneto attain his object; how he was sure that the escape of fire-damptook place at the very end of the farthest gallery in its western part,because he had provoked small and partial explosions, or rather littleflames, enough to show the nature of the gas, which escaped in a smalljet, but with a continuous flow.
An hour after leaving the cottage, James Starr and his two companionshad gone a distance of four miles. The engineer, urged by anxiety andhope, walked on without noticing the length of the way. He ponderedover all that the old miner had told him, and mentally weighed all thearguments which the latter had given in support of his belief. He agreedwith him in thinking that the continued emission of carburetted hydrogencertainly showed the existence of a new coal-seam. If it had been merelya sort of pocket, full of gas, as it is sometimes found amongst therock, it would soon have been empty, and the phenomenon have ceased.But far from that. According to Simon Ford, the fire-damp escapedincessantly, and from that fact the existence of an important vein mightbe considered certain. Consequently, the riches of the Dochart pit werenot entirely exhausted. The chief question now was, whether this wasmerely a vein which would yield comparatively little, or a bed occupyinga large extent.
Harry, who preceded his father and the engineer, stopped.
"Here we are!" exclaimed the old miner. "At last, thank Heaven! youare here, Mr. Starr, and we shall soon know." The old overman's voicetrembled slightly.
"Be calm, my man!" said the engineer. "I am as excited as you are, butwe must not lose time."
The gallery at this end of the pit widened into a sort of dark cave.No shaft had been pierced in this part, and the gallery, bored into thebowels of the earth, had no direct communication with the surface of theearth.
James Starr, with intense interest, examined the place in which theywere standing. On the walls of the cavern the marks of the pick couldstill be seen, and even holes in which the rock had been blasted, nearthe termination of the working. The schist was excessively hard, and ithad not been necessary to bank up the end of the tunnel where the workshad come to an end. There the vein had failed, between the schist andthe tertiary sandstone. From this very place had been extracted the lastpiece of coal from the Dochart pit.
"We must attack the dyke," said Ford, raising his pick; "for at theother side of the break
, at more or less depth, we shall assuredly findthe vein, the existence of which I assert."
"And was it on the surface of these rocks that you found out thefire-damp?" asked James Starr.
"Just there, sir," returned Ford, "and I was able to light it only bybringing my lamp near to the cracks in the rock. Harry has done it aswell as I."
"At what height?" asked Starr.
"Ten feet from the ground," replied Harry.
James Starr had seated himself on a rock. After critically inhaling theair of the cavern, he gazed at the two miners, almost as if doubtingtheir words, decided as they were. In fact, carburetted hydrogen is notcompletely scentless, and the engineer, whose sense of smell was verykeen, was astonished that it had not revealed the presence of theexplosive gas. At any rate, if the gas had mingled at all with thesurrounding air, it could only be in a very small stream. There was nodanger of an explosion, and they might without fear open the safety lampto try the experiment, just as the old miner had done before.
What troubled James Starr was, not lest too much gas mingled with theair, but lest there should be little or none.
"Could they have been mistaken?" he murmured. "No: these men know whatthey are about. And yet--"
He waited, not without some anxiety, until Simon Ford's phenomenonshould have taken place. But just then it seemed that Harry, likehimself, had remarked the absence of the characteristic odor offire-damp; for he exclaimed in an altered voice, "Father, I should saythe gas was no longer escaping through the cracks!"
"No longer!" cried the old miner--and, pressing his lips tight together,he snuffed the air several times.
Then, all at once, with a sudden movement, "Hand me your lamp, Harry,"he said.
Ford took the lamp with a trembling hand. He drew off the wire gauzecase which surrounded the wick, and the flame burned in the open air.
As they had expected, there was no explosion, but, what was moreserious, there was not even the slight crackling which indicates thepresence of a small quantity of firedamp. Simon took the stick whichHarry was holding, fixed his lamp to the end of it, and raised it highabove his head, up to where the gas, by reason of its buoyancy, wouldnaturally accumulate. The flame of the lamp, burning straight and clear,revealed no trace of the carburetted hydrogen.
"Close to the wall," said the engineer.
"Yes," responded Ford, carrying the lamp to that part of the wall atwhich he and his son had, the evening before, proved the escape of gas.
The old miner's arm trembled whilst he tried to hoist the lamp up. "Takemy place, Harry," said he.
Harry took the stick, and successively presented the lamp to thedifferent fissures in the rock; but he shook his head, for of thatslight crackling peculiar to escaping fire-damp he heard nothing. Therewas no flame. Evidently not a particle of gas was escaping through therock.
"Nothing!" cried Ford, clenching his fist with a gesture rather of angerthan disappointment.
A cry escaped Harry.
"What's the matter?" asked Starr quickly.
"Someone has stopped up the cracks in the schist!"
"Is that true?" exclaimed the old miner.
"Look, father!" Harry was not mistaken. The obstruction of the fissureswas clearly visible by the light of the lamp. It had been recently donewith lime, leaving on the rock a long whitish mark, badly concealed withcoal dust.
"It's he!" exclaimed Harry. "It can only be he!"
"He?" repeated James Starr in amazement.
"Yes!" returned the young man, "that mysterious being who haunts ourdomain, for whom I have watched a hundred times without being able toget at him--the author, we may now be certain, of that letter which wasintended to hinder you from coming to see my father, Mr. Starr, and whofinally threw that stone at us in the gallery of the Yarrow shaft! Ah!there's no doubt about it; there is a man's hand in all that!"
Harry spoke with such energy that conviction came instantly and fullyto the engineer's mind. As to the old overman, he was already convinced.Besides, there they were in the presence of an undeniable fact--thestopping-up of cracks through which gas had escaped freely the nightbefore.
"Take your pick, Harry," cried Ford; "mount on my shoulders, my lad!I am still strong enough to bear you!" The young man understood in aninstant. His father propped himself up against the rock. Harry got uponhis shoulders, so that with his pick he could reach the line of thefissure. Then with quick sharp blows he attacked it. Almost directlyafterwards a slight sound was heard, like champagne escaping from abottle--a sound commonly expressed by the word "puff."
Harry again seized his lamp, and held it to the opening. There wasa slight report; and a little red flame, rather blue at its outline,flickered over the rock like a Will-o'-the-Wisp.
Harry leaped to the ground, and the old overman, unable to contain hisjoy, grasped the engineer's hands, exclaiming, "Hurrah! hurrah! hurrah!Mr. Starr. The fire-damp burns! the vein is there!"