〃Look；〃 Ted said； 〃red； blue； yellow。 Primary colors。 This is a very big break。〃
〃Why？〃 Norman said。
〃Because it suggests that the aliens have the same sensory equipment that we do…they may see the universe the same ＇＇65＇＇ way； visually； in the same colors； utilizing the same part of the electromagnetic spectrum。 That's going to help immeasurably in making contact with them。 And those black…and…white markings 。。。 that must be some of their writing！ Can you imagine！ Alien writing！〃 He smiled enthusiastically。 〃This is a great moment；〃 he said。 〃I feel truly privileged to be here。〃
〃Focus；〃 Barnes called。 〃Focusing now； sir。〃
The image became even more blurred。 〃No； the other way。〃
〃Yes Sir。 Focusing now。〃
The image changed； slowly resolved into sharp focus。 〃Uh…oh；〃 Ted said； staring at the screen。
They now saw that the blurred knobs were actually three colored buttons： yellow； red； and blue。 The buttons were each an inch in diameter and had knurled or machined edges。 The symbols above the buttons resolved sharply into a series of neatly stenciled labels。
From left to right the labels read： 〃Emergency Ready；〃 〃Emergency Lock；〃 and 〃Emergency Open。〃
In English。
There was a moment of stunned silence。 And then； very softly； Harry Adams began to laugh。
THE SPACECRAFT
〃That's English；〃 Ted said； staring at the screen。 〃Written English。〃
〃Yeah；〃 Harry said。 〃Sure is。〃
〃What's going on？〃 Ted said。 〃Is this some kind of joke？〃
〃No；〃 Harry said。 He was calm； oddly detached。
＇＇66＇＇ 〃How could this spacecraft be three hundred years old； and carry instructions in modem English？〃
〃Think about it；〃 Harry said。
Ted frowned。 〃Maybe；〃 he said； 〃this alien spacecraft is somehow presenting itself to us in a way that will make us fortable。〃
〃Think about it some more；〃 Harry said。
There was a short silence。 〃Well； if it is an alien spacecraft…〃
〃It's not an alien spacecraft；〃 Harry said。
There was another silence。 Then Ted said； 〃Well； why don't you just tell us all what it is； since you're so sure of yourself！〃
〃All right；〃 Harry said。 〃It's an American spacecraft。〃
〃An American spacecraft？ Half a mile long？ Made with technology we don't have yet？ And buried for three hundred years？〃
〃Of course；〃 Harry said。 〃It's been obvious from the start。 Right； Captain Barnes？〃
〃We had considered it；〃 Barnes admitted。 〃The President had considered it。〃
〃That's why you didn't inform the Russians。〃
〃Exactly。〃
By now Ted was pletely frustrated。 He clenched his fists； as if he wanted to hit someone。 He looked from one person to another。 〃But how did you know？〃
〃The first clue；〃 Harry said； 〃came from the condition of the craft itself。 It shows no damage whatever。 Its condition is pristine。 Yet any spacecraft that crashes in water will be damaged。 Even at low entry velocities…say two hundred miles an hour…the surface of water is as hard as concrete。 No matter how strong this craft is； you would expect some degree of damage from the impact with the water。 Yet it has no damage。〃
〃Meaning？〃
〃Meaning it didn't land in the water。〃
〃I don't understand。 It must have flown here…〃
〃…It didn't fly here。 It arrived here。〃
〃From where？〃
＇＇67＇＇ 〃From the future；〃 Harry said。 〃This is some kind of Earth craft that was…will be…made in the future； and has traveled backward in time； and appeared under our ocean； several hundred years ago。〃
〃Why would people in the future do that？〃 Ted groaned。 He was clearly unhappy to be deprived of his alien craft； his great historical moment。 He slumped in a chair and stared dully at the monitor screens。
〃I don't know why people in the future would do that；〃 Harry said。 〃We're not there yet。 Maybe it was an accident。 Unintended。〃
〃Let's go ahead and open it up；〃 Barnes said。
〃Opening； sir。〃
The robot hand moved forward； toward the 〃Open〃 button。 The hand pressed several times。 There was a clanking sound； but nothing happened。
〃What's wrong？〃 Barnes said。
〃Sir； we're not able to impact the button。 The extensor arm is too large to fit inside the panel。〃
〃Great。〃
〃Shall I try the probe？〃
〃Try the probe。〃
The claw hand moved back； and a thin needle probe extended out toward the button。 The probe slid forward； adjusted position delicately； touched the button。 It pushed…and slipped off。
〃Trying again； sir。〃
The probe again pressed the button； and again slid off。
〃Sir； the surface is too slippery。〃
〃Keep trying。〃
〃You know；〃 Ted said thoughtfully； 〃this is still a remarkable situation。 In one sense； it's even more remarkable than contact with extraterrestrials。 I was already quite certain that extraterrestrial life exists in the universe。 But time travel！ Frankly； as an astrophysicist I had my doubts。 From everything we know； it's impossible； contradicted by the laws of physics。 And yet now we have proof that time travel is possible…and that our own species will do it in the future！〃
Ted was smiling； wide…eyed； and happy again。 You had to ＇＇68＇＇ admire him； Norman thought…he was so wonderfully irrepressible。
〃And here we are；〃 Ted said； 〃on the threshold of our first contact with our species from the future！ Think of it！ We are going to meet ourselves from some future time！〃
The probe pressed again； and again； without success。
〃Sir； we cannot impact the button。〃
〃I see that；〃 Barnes said； standing up。 〃Okay； shut it down and get it out of there。 Ted； looks like you're going to get your wish after all。 We'll have to go in and open it up manually。 Let's suit up。〃
INTO THE SHIP
In the changing room in cylinder A； Norman stepped into his suit。 Tina and Edmunds helped fit the helmet over his head； and snap…locked the ring at the neck。 He felt the heavy weight of the rebreather tanks on his back； the straps pressed into his shoulders。 He tasted metallic air。 There was a crackle as his helmet inter came on。
The first words he heard were 〃What about 'At the threshold of a great opportunity for the human species'？〃 Norman laughed； grateful for the break in the tension。
〃You find it funny？〃 Ted asked； offended。
Norman looked across the room at the suited man with 〃FIELDING〃 stenciled on his yellow helmet。
〃No；〃 Norman said。 〃I'm just nervous。〃
〃Me； too；〃 Beth said。
〃Nothing to it；〃 Barnes said。
〃Trust me。〃
〃What are the three biggest lies in DH…8？〃 Harry said； and they laughed again。
They crowded together into the tiny airlock； bumping helmeted heads； and the bulkhead hatch to the left was sealed； ＇＇69＇＇ the wheel spinning。 Barnes said； 〃Okay； folks； just breathe easy。〃 He opened the lower hatch； exposing black water。 The water did not rise into the partment。 〃The habitat's on positive pressure；〃 Barnes said。 〃The level won't e up。 Now watch me； and do this the way I do。 You don't want to tear your suit。〃 Moving awkwardly with the weight of the tanks； he crouched down by the hatch； gripped the side handholds； and let go； disappearing with a soft splash。
One by one； they dropped down to the floor of the ocean。 Norman gasped as near…freezing water enveloped his suit； immediately he heard the hum of a tiny fan as the electrical heaters in his suit activated。 His feet touched soft muddy ground。 He looked around in the darkness。 He was standing beneath the habitat。 Directly ahead； a hundred yards away； was the glowing rectangular grid。 Barnes was already striding forward； leaning into the current； moving slowly like a man on the moon。
〃Isn't this fantastic？〃
〃Calm down； Ted；〃 Harry said。
Beth said； 〃Actually； it's odd how little life there is down here。 Have you noticed？ Not a sea fan； not a slug； not a sponge； not a solitary fish。 Nothing but empty brown sea floor。 This must be one of those dead spots in the Pacific。〃
A bright light came on behind him； Norman's own shadow was cast forward on the bottom。 He looked back and saw Edmunds holding a camera and light in a bulky waterproof housing。
〃We recording all this？〃
〃Yes； sir。〃
〃Try not to fall down； Norman；〃 Beth laughed。
〃I'm trying。〃
They were closer now to the grid。 Norman felt better seeing the other divers working there。 To the right was the high fin； extending out of the coral； an enormous； smooth dark surface dwarfing them as it rose toward the surface。
Barnes led them past the fin and down into a tunnel cut in the coral。 The tunnel was sixty feet long； narrow； strung with lights。 They walked single file。 It felt like going down into a mine； Norman thought。
＇＇70＇＇ 〃This what the divers cut？〃
〃That's right。〃
Norman saw a boxy； corrugated…steel structure surrounded by pressure tanks。
〃Airlock ahead。 We're almost there；〃 Barnes said。 〃Everybody okay？〃
〃So far；〃 Harry said。
They entered the airlock； and Barnes closed the door。 Air hissed loudly。 Norman watched the water recede； down past his faceplate； then his waist； his knees； then to the floor。 The hissing stopped； and they passed through another door； sealing it behind them。
Norman turned to the metal hull of the spaceship。 The robot had been moved aside。 Norman felt very much as if he were standing alongside a big jetliner…a curved metal surface； and a flush door。 The metal was a dull gray； which gave it an ominous quality。 Despite himself； Norman was nervous。 Listening to the way the others were breathing； he sensed they were nervous； too。
〃Okay？〃 Barnes said。 〃Everybody h