"There is a house on fire," said Challenger at last, pointing to a column of smoke which rose above the trees. "There will, I expect, be many such-possibly whole cities in flames-when we consider how many folk may have dropped with lights in their hands. The fact of combustion is in itself enough to show that the proportion of oxygen in the atmosphere is normal and that it is the ether which is at fault. Ah, there you see another blaze on the top of Crowborough Hill. It is the golf clubhouse, or I am mistaken. There is the church clock chiming the hour. It would interest our philosophers to know that man-made mechanisms has survived the race who made it."
"By George!" cried Lord John, rising excitedly from his chair. "What's that puff of smoke? It's a train."
We heard the roar of it, and presently it came flying into sight, going at what seemed to me to be a prodigious speed. Whence it had come, or how far, we had no means of knowing. Only by some miracle of luck could it have gone any distance. But now we were to see the terrific end of its career. A train of coal trucks stood motionless upon the line. We held our breath as the express roared along the same track. The crash was horrible. Engine and carriages piled themselves into a hill of splintered wood and twisted iron. Red spurts of flame flickered up from the wreckage until it was all ablaze. For half an hour we sat with hardly a word, stunned by the stupendous sight.
"Poor, poor people!" cried Mrs. Challenger at last, clinging with a whimper to her husband's arm.
"My dear, the passengers on that train were no more animate than the coals into which they crashed or the carbon which they have now become," said Challenger, stroking her hand soothingly. "It was a train of the living when it left Victoria, but it was driven and freighted by the dead long before it reached its fate."
"All over the world the same thing must be going on," said I as a vision of strange happenings rose before me. "Think of the ships at sea-how they will steam on and on, until the furnaces die down or until they run full tilt upon some beach. The sailing ships too-how they will back and fill with their cargoes of dead sailors, while their timbers rot and their joints leak, till one by one they sink below the surface. Perhaps a century hence the Atlantic may still be dotted with the old drifting derelicts."
"And the folk in the coal-mines," said Summerlee with a dismal chuckle. "If ever geologists should by any chance live upon earth again they will have some strange theories of the existence of man in carboniferous strata."
"I don't profess to know about such things," remarked Lord John, "but it seems to me the earth will be `To let, empty,' after this. When once our human crowd is wiped off it, how will it ever get on again?"
"The world was empty before," Challenger answered gravely. "Under laws which in their inception are beyond and above us, it became peopled. Why may the same process not happen again?"
"My dear Challenger, you can't mean that?"
"I am not in the habit, Professor Summerlee, of saying things which I do not mean. The observation is trivial." Out went the beard and down came the eyelids.
"Well, you lived an obstinate dogmatist, and you mean to die one," said Summerlee sourly.
"And you, sir, have lived an unimaginative obstructionist and never can hope now to emerge from it."
"Your worst critics will never accuse you of lacking imagination," Summerlee retorted.
"Upon my word!" said Lord John. "It would be like you if you used up our last gasp of oxygen in abusing each other. What can it matter whether folk come back or not? It surely won't be in our time." "In that remark, sir, you betray your own very pronounced limitations," said Challenger severely. "The true scientific mind is not to be tied down by its own conditions of time and space. It builds itself an observatory erected upon the border line of present, which separates the infinite past from the infinite future. From this sure post it makes its sallies even to the beginning and to the end of all things. As to death, the scientific mind dies at its post working in normal and methodic fashion to the end. It disregards so petty a thing as its own physical dissolution as completely as it does all other limitations upon the plane of matter. Am I right, Professor Summerlee?"
Summerlee grumbled an ungracious assent.
"With certain reservations, I agree," said he.
"The ideal scientific mind," continued Challenger-"I put it in the third person rather than appear to be too self-complacent-the ideal scientific mind should be capable of thinking out a point of abstract knowledge in the interval between its owner falling from a balloon and reaching the earth. Men of this strong fibre are needed to form the conquerors of nature and the bodyguard of truth."
"It strikes me nature's on top this time," said Lord John, looking out of the window. "I've read some leadin' articles about you gentlemen controllin' her, but she's gettin' a bit of her own back."
"It is but a temporary setback," said Challenger with conviction. "A few million years, what are they in the great cycle of time? The vegetable world has, as you can see, survived. Look at the leaves of that plane tree. The birds are dead, but the plant flourishes. From this vegetable life in pond and in marsh will come, in time, the tiny crawling microscopic slugs which are the pioneers of that great army of life in which for the instant we five have the extraordinary duty of serving as rear guard. Once the lowest form of life has established itself, the final advent of man is as certain as the growth of the oak from the acorn. The old circle will swing round once more."
"But the poison?" I asked. "Will that not nip life in the bud?"
"The poison may be a mere stratum or layer in the ether-a mephitic Gulf Stream across that mighty ocean in which we float. Or tolerance may be established and life accommodate itself to a new condition. The mere fact that with a comparatively small hyperoxygenation of our blood we can hold out against it is surely a proof in itself that no very great change would be needed to enable animal life to endure it."