Capps, it seemed to me, was unusually anxious to have the visit over.At any rate, while Kennedy and Paddy were still crawling about the shield, he stood aside, now and then giving the men an order and apparently forgetful of us.
My own curiosity was quickly satisfied, and I sat down on a pile of the segments out of which the successive rings of the tunnel were made.As I sat there waiting for Kennedy, I absently reached into my pocket and pulled out a cigarette and lighted it.It burned amazingly fast, as if it were made of tinder, the reason being the excess of oxygen in the compressed air.I was looking at it in astonishment, when suddenly I felt a blow on my hand.It was Capps.
"You chump!" he shouted as he ground the cigarette under his boot.
"Don't you know it is dangerous to smoke in compressed air?""Why, no," I replied, smothering my anger at his manner."No one said anything about it.""Well, it is dangerous, and Orton's a fool to let greenhorns come in here.""And to whom may it be dangerous?" I heard a voice inquire over my shoulder.It was Kennedy."To Mr.Jameson or the rest of us?""Well," answered Capps, "I supposed everybody knew it was reckless, and that he would hurt himself more by one smoke in the air than by a hundred up above.That's all."He turned on Kennedy sullenly, and started to walk back up the tunnel.But I could not help thinking that his manner was anything but solicitude for my own health.I could just barely catch his words over the tunnel telephone some feet away.I thought he said that everything was going along all right and that he was about to start back again.Then he disappeared in the mist of the tube without even nodding a farewell.
Kennedy and I remained standing, not far from the outlet of the pipe by which the compressed air was being supplied in the tunnel from the compressors above, in order to keep the pressure up to the constant level necessary.I saw Kennedy give a hurried glance about, as if to note whether any one were looking at us.No one was.With a quick motion he reached down.In his hand was a stout little glass flask with a tight-fitting metal top.For a second he held it near the outlet of the pipe; then he snapped the top shut and slipped it back into his pocket as quickly as he had produced it.
Slowly we commenced to retrace our steps to the air-lock, our curiosity satisfied by this glimpse of one of the most remarkable developments of modern engineering.
"Where's Paddy?" asked Kennedy, stopping suddenly."We've forgotten him.""Back there at the shield, I suppose," said I."Let's whistle and attract his attention.
I pursed up my lips, but if I had been whistling for a million dollars I couldn't have done it.
Craig laughed."Walter, you are indeed learning many strange things.
You can't whistle in compressed air.
I was too chagrined to answer.First it was Capps; now it was my own friend Kennedy chaffing me for my ignorance.I was glad to see Paddy's huge form looming in the semi-darkness.He had seen that we were gone and hurried after us.
"Won't ye stay down an' see some more, gintlemen?" he asked."Or have ye had enough of the air? It seems very smelly to me this mornin' - I don't blame ye.I guess them as doesn't have to stay here is satisfied with a few minutes of it.""No, thanks, I guess we needn't stay down any longer," replied Craig."I think I have seen all that is necessary - at least for the present.Capps has gone out ahead of us.I think you can take us out now, Paddy.I would much rather have you do it than to go with anybody else."Coming out, I found, was really more dangerous than going in, for it is while coming out of the that men are liable to get the bends.
Roughly, half a minute should be consumed in coming out from each pound of pressure, though for such high pressures as we had been under, considerably more time was required in order to do it safely.
We spent about half an hour in the air-lock, I should judge.
Paddy let the air out of the lock by turning on a valve leading to the outside, normal atmosphere.Thus he let the air out rapidly at first until we had got down to half the pressure of the tunnel.The second half he did slowly, and it was indeed tedious, but it was safe.There was at=20first a hissing sound when he opened the valve, and it grew colder in the lock, since air absorbs heat from surrounding objects when it expands.We were glad to draw sweaters on over our heads.It also grew as misty as a London fog as the water-vapour in the air was condensed.
At last the hiss of escaping air ceased.The door to the modern dungeon of science grated open.We walked out of the lock to the elevator shaft and were hoisted up to God's air again.We gazed out across the river with its waves dancing in the sunlight.There, out in the middle, was a wreath of bubbles on the water.That marked the end of the tunnel, over the shield.Down beneath those bubbles the sand-hogs were rooting.But what was the mystery that the tunnel held in its dark, dank bosom? Had Kennedy a clue?
"I think we had better wait around a bit," remarked Kennedy, as we sipped our hot coffee in the dressing-room and warmed ourselves from the chill of coming out of the lock."In case anything should happen to us and we should get the bends this is the place for us, near the medical lock, as it is called - that big steel cylinder over there, where we found Orton.The best cure for the bends is to go back under the air-recompression they call it.The renewed pressure causes the gas in the blood to contract again, and thus it is eliminated - sometimes.At any rate, it is the best-known cure and considerably reduces the pain in the worst cases.When you have a bad case like Orton's it means that the damage is done; the gas has ruptured some veins.Paddy was right.Only time will cure that."Nothing happened to us, however, and in a couple of hours we dropped in on Orton at the hospital where he was slowly convalescing.
"What do you think of the case?" he asked anxiously.