Munro asked； 〃Can we make a better perimeter defense？〃
〃Damn right we can；〃 Ross said。 〃I'll give you the next generation perimeter…it'll stop anything except elephants and rhinos。〃 But she didn't sound convinced。
Late in the afternoon； they came upon the remains of the first ERTS Congo camp。 They nearly missed it； for during the intervening eight days the jungle vines and creepers had already begun to grow back over it； obliterating all traces。 There was not much left…a few shreds of orange nylon； a dented aluminum cooking pan； the crushed tripod； and the broken video camera； its green circuit boards scattered across the ground。 They found no bodies； and since the light was fading they pressed on。
Amy was distinctly agitated； She signed； No go。
Peter Elliot paid no attention。
Bad place old place no go。
〃We go； Amy；〃 he said。
Fifteen minutes later they came to a break in the overhanging trees。 Looking up； they saw the dark cone of Mukenko rising above the forest； and the faint crossed green beams of the lasers glinting in the humid air。 And directly beneath the beams were the moss…covered stone blocks； half concealed in jungle foliage； of the Lost City of Zinj。
Elliot turned to look at Amy。
Amy was gone。
4。 WEIRD
HE COULD NOT BELIEVE IT。
At first he thought she was just punishing him； running off to make him sorry for shooting the dart at her on the river。 He explained to Munro and Ross that she was capable of such things； and they spent the next half hour wandering through the jungle； calling her name。 But there was no response； just the eternal silence of the rain forest。 The half hour became an hour； then almost two hours。
Elliot was panic…stricken。
When she still did not emerge from the foliage； another possibility had to be considered。 〃Maybe she ran off with the last group of gorillas；〃 Munro said。
〃Impossible；〃 Elliot said。
〃She's seven； she's near maturity。〃 Munro shrugged。
〃She is a gorilla。〃 …
〃Impossible；〃 Elliot insisted。
But he knew what Munro was saying。 Inevitably； people who raised apes found at a certain point they could no longer keep them。 With maturity the animals became too large； too powerful； too much their own species to be controllable。 It was no longer possible to put them in diapers and pretend they were cute humanlike creatures。 Their genes coded inevitable differences that ultimately became impossible to overlook。
〃Gorilla troops aren't closed；〃 Munro reminded him。 〃They accept strangers； particularly female strangers。〃
〃She wouldn't do that；〃 Elliot insisted。 〃She couldn't。〃
Amy had been raised from infancy among human beings。 She was much more familiar with the Westernized world of freeways and drive…ins than she was with the jungle。 If Elliot drove his car past her favorite drive…in； she was quick to tap his shoulder and point out his error。 What did she know of the jungle？ It was as alien to her as it was to Elliot himself。 And not only that… 〃We'd better make camp；〃 Ross said； glancing at her watch。 〃She'll e back…if she wants to。 After all；〃 she said； 〃we didn't leave her。 She left us。〃
They had brought a bottle of Dom Perignon champagne but nobody was in a mood to celebrate。 Elliot was remorseful over the loss of Amy； the others were horrified by what they had seen of the earlier camp； with night rapidly falling； there was much to do to setup the ERTS system known as WEIRD （Wilderness Environmental Intruder Response Defenses）。
The exotic WEIRD technology recognized the fact that perimeter defenses were traditional throughout the history of Congo exploration。 More than a century before； Stanley observed that 〃no camp is to be considered plete until it is fenced around by bush or trees。〃 In the years since there was little reason to alter the essential nature of that instruction。
But defensive technology had changed； and the WEIRD system incorporated all the latest innovations。
Kahega and his men inflated the silvered Mylar tents； arranging them close together。 Ross directed the placement of the tubular infrared night lights on telescoping tripods。 These were positioned shining outward around the camp。
Next the perimeter fence was installed。 This was a lightweight metalloid mesh； more like cloth than wire。 Attached to stakes； it pletely enclosed the campsite； and when hooked to the transformer carried 10；000 volts of electrical current。 To reduce drain on the fuel cells； the current was pulsed at four cycles a second； creating a throbbing； intermittent hum。
Dinner on the night of June 20 was rice with rehydrated Creole shrimp sauce。 The shrimps did not rehydrate well； remaining little cardboard…tasting chunks in the mix； but nobody plained about this failure of twentieth…century technology as they glanced around them at the deepening jungle darkness。
Munro positioned the sentries。 They would stand …four…hour watches； Munro announced that he； Kahega； and Elliot would take the first watch。
With night goggles in place； the sentries looked like mysterious grasshoppers peering out at the jungle。 The night goggles intensified ambient light and overlaid this on the preexisting imagery； rimming it in ghostly green。 Elliot found the goggles heavy； and the electronic view through them difficult to adjust to。 He pulled them off after several minutes； and was astonished to see that the jungle was inky black around him。 He put them back on hastily。
The night passed quietly； without incident。
DAY 9： ZINJ
June 21； 1979
1。Tiger Tail
THEIR ENTRANCE INTO THE LOST CITY OF ZINJ ON the morning of June 21 was acplished with none of the mystery and romance of nineteenth…century accounts of similar journeys。 These twentieth…century explorers sweated and grunted under a burdensome load of technical equipment… optical range finders； data…lock passes； RF directionals with attached transmitters； and microwave transponders…all deemed essential to the modem high…speed evaluation of a ruined archaeological site。
They were only interested in diamonds。 Schliemann had been only interested in gold when he excavated Troy； and he had devoted three years to it。 Ross expected to find her diamonds in three days。
According to the ERTS puter simulation the best way to do this was to draw up a ground plan of the city。 With a plan in hand； it would be relatively simple to deduce mine locations from the arrangement of urban structures。
They expected a usable plan of the city within six hours。 Using RF transponders； they had only to stand in each of the four corners of a building； pressing the radio beeper at each corner。 Back in camp； two widely spaced receivers recorded their signals so that their puter could plot them in two dimensions。 But the ruins were extensive； covering more than three square kilometers。 A radio survey would separate them widely in dense foliage…and； considering what had happened to the previous expedition； this seemed unwise。
Their alternative was what ERTS called the non…systematic Survey； or 〃the tiger…tail approach。〃 （It was a joke at ERTS that one way to find a tiger was to keep walking until you stepped on its tail。） They moved through the ruined buildings； avoiding slithering snakes and giant spiders that scurried into dark recesses。 The spiders were the size of a man's hand； and to Ross's astonishment made a loud clicking noise。
They noticed that the stonework was of excellent quality； although the limestone in many places was pitted and crumbling。 And everywhere they saw the half…moon curve of doors and windows； which seemed to be a cultural design motif。
But aside from that curved shape； they found almost nothing distinctive about the rooms they passed through。 In general； the rooms were rectangular and roughly the same size； the walls were bare； lacking decoration。 After so many intervening centuries they found no artifacts at all…although Elliot finally came upon a pair of disc…shaped stone paddles； which they presumed had been used to grind spices or grain。
The bland； characterless quality of the city grew more disturbing as they continued； it was also inconvenient； since they had no way to refer to one place or another； they began assigning arbitrary name