〃Sir; you are in very good health for your age and lifestyle。〃
〃And what about going down there?〃 Norman asked; half hoping he wouldnt be able to go。
〃Down there? Ive talked with Captain Barnes。 Shouldnt be any problem at all; sir。 If youll just e this way to the briefing; sir 。。。〃
The others were sitting around in the briefing room; with Styrofoam cups of coffee。 Norman felt glad to see them。 He dropped into a chair next to Harry。 〃Jesus; did you have the damn physical?〃
〃Yeah;〃 he said。 〃Had it yesterday。〃
〃They stuck me in the leg with this long needle;〃 Norman said。
〃Really? They didnt do that to me。〃
〃And how about breathing with that clip on your nose?〃
〃I didnt do that; either;〃 Harry said。 〃Sounds like you got some special treatment; Norman。〃
Norman was thinking the same thing; and he didnt like the implications。 He felt suddenly tired。
〃All right; men; weve got a lot to cover and just three hours to do it;〃 a brisk man said; turning off the lights as he came into the room。 Norman hadnt even gotten a good look at him。 Now it was just a voice in the dark。 〃As you know; Daltons law governs partial pressures of mixed gases; or; as represented here in algebraic form 。。。〃
The first of the graphs flashed up。
PPa = Ptot x % Vola
''44'' 〃Now lets review how calculation of the partial pressure might be done in atmospheres absolute; which is the most mon procedure we employ…〃
The words were meaningless to Norman。 He tried to pay attention; but as the graphs continued and the voice droned on; his eyes grew heavier and he fell asleep。
〃…be taken down in the submarine and once in the habitat module you will be pressurized to thirty…three atmospheres。 At that time you will be switched over to mixed gases; since it is not possible to breathe Earth atmosphere beyond eighteen atmospheres…〃
Norman stopped listening。 These technical details only filled him with dread。 He went back to sleep; awakening only intermittently。
〃…since oxygen toxicity only occurs when the PO2 exceeds point 7 ATA for prolonged periods…
〃…nitrogen narcosis; in which nitrogen behaves like an anesthetic; will occur in mixed…gas atmospheres if partial pressures exceeds 1。5 ATA in the DDS…
〃…demand open circuit is generally preferable; but you will be using semiclosed circuit with inspired fluctuations of 608 to 760 millimeters…〃
He went back to sleep。
When it was over; they walked back to their rooms。 〃Did I miss anything?〃 Norman said。
〃Not really。〃 Harry shrugged。 〃Just a lot of physics。〃
In his tiny gray room; Norman got into bed。 The glowing wall clock said 2300。 It took him a while to figure out that that was 11:00 p。m。 In nine more hours; he thought; I will begin the descent。
Then he slept。
THE DEEP
DESCENT
In the morning light; the submarine Charon V bobbed on the surface; riding on a pontoon platform。 Bright yellow; it looked like a childs bathtub toy sitting on a deck of oildrums。
A rubber Zodiac launch took Norman over; and he climbed onto the platform; shook hands with the pilot; who could not have been more than eighteen; younger than his son; Tim。
〃Re