Green for Danger by Christianna Brand Page A

anæsthesia we use it with oxygen; those are the two outside cylinders. The green one in the middle is CO2—carbon dioxide; but we needn’t bother about it, because we didn’t use it on Higgins, and in fact it very seldom is used, except in special cases.”
    â€œIs that why there’s only one tube of it, and two of each of the others?”
    â€œYes, that’s right. There’s a spare of nitrous oxide and a spare of oxygen; they’re connected up, and in emergency you only have to switch on the reducing valve; but, again, they don’t concern Higgins, because as it happens we were using fresh cylinders of both, so of course we didn’t run short. Anyway, we didn’t have time to run short.”
    â€œNo possibility that the reducing valve wasn’t turned off?”
    â€œIt wouldn’t have made any difference; after all, they were still just gas and oxygen, and the flow is regulated up here.” He glanced at the glass jar on the bracket. “But, anyway, they were both firmly turned off, because of course we went over the whole thing afterwards.”
    Cockie fiddled with his cigarette, longing to light it, but overawed by the formidable cleanliness of his surroundings. He said, rocking backwards and forwards slowly, from his toes to his heels: “What about all these rubber tubes and things?”
    The Y-tubes led from the cylinders, black from the nitrous oxide, red from the oxygen and green from the central cylinder of carbon dioxide, to the first of the glass jars hanging from the bracket above the trolley; and each was controlled by a tap. Two of the jars were coloured, but the first was plain; it was half filled with water, and three metal tubes, each with a line of little holes, like a flute, stuck down into the jar and well below the surface of the water. Barney turned a tap and bubbles appeared from the first tube at the water line, and spread down to the bottom of the tube as the tap was turned more fully on. “The nitrous oxide,” said Barnes. He left it bubbling and turned on another tap, and the third tube bubbled. “That’s the oxygen. They mix above the surface of the water and pass along a single metal pipe to the mask over the patient’s face. If we used the carbon dioxide, it would bubble out of the centre tube; but we didn’t.” He let a line of bubbles run up and down the centre tube for a moment, and then switched off.
    â€œSo only these two are being used,” summed up Cockrill, pointing to the two outside cylinders with the toe of his shoe. “And only the corresponding outside tubes in the jar are bubbling?”
    â€œYes, that’s right.”
    â€œAnd that’s all that was used on this man Higgins?”
    â€œYes, that’s right,” said Barney again. He got up off the stool. “You sit down and try.”
    Cockie sat down, wrinkling his nose in disgust at the sickly familiar smell of ether and antiseptic, but concentrating deeply upon the trolley in front of him. He twiddled the taps for a minute or so, and bubbles played madly up and down the little tubes. “What about all these bits and pieces—bottles and jars and things?”
    â€œOh, those are mostly emergency stuff; adrenalin and strychnine and so forth; and the usual collection of gags and tongue clips and what-have-you. This funny short, fat red tube is the air-way; we put it down the patient’s throat when he’s well under, to keep it from closing up or getting obstructed. It’s got a metal mouthpiece, you see, to keep him from biting on it and closing it.”
    â€œCharming,” said Cockrill dryly. He looked at the rows of bottles and jars and instruments. “Which of these was actually used on Higgins?”
    â€œWell, none of them until things began to go wrong. Then I put in the air-way—that’s why I mentioned it to you; and, of course, I used a gag between his teeth while I put it