but--" A scratching at the door,accompanied by a high squeak, interrupted him.

  * * * * *

  To Jim's shouted "Come in," there entered a Venusian, whose redrosette fastened to the green scales of his skin marked him anoverseer. In the thread-like fingers of his hand he held a time-sheet,but the nervous pulsing of his gill-membranes caused Holcomb toexclaim anxiously: "What's wrong, Ran-los? No accident, I hope?"

  The shrill combination of squeaks and twitterings that came from theman-reptile's toothless mouth meant nothing to the Scot, but Jim'slast service had been on Venus and he had gained a working knowledgeof the language. Finally the interchange was ended, and Ran-los bowedhimself out. Jim turned to his companion.

  "There's some more queer stuff for you, Angie. Just beforeshift-change, Ran-los heard odd sounds from the other side of thebarrier at the end of gallery M-39. Says they seemed like signals o'some kind. He's a wise old bird and if he's worried about somethingit's damn well worth lookin' into. I don't know whether to find outfirst what's happened to Darl, or--"

  Again there was an interruption; this time from the usually silentradio-communication set in the far corner. Jim leaped to theinstrument and snapped on the head-set. Angus leaned over him,watching his intent face.

  Faintly, as from an immense distance, came the thin whistle ofspace-radio. "S-W-A ... S-W-A ... S-W-A...." The general attentionsignal for all Earth's far-flung outposts from Jupiter to Mercury! Thesignal was coming from "M-I-T-A," the Earth company's home station onthe Moon, outside the Heaviside layer. "S-W-A ... S-W-A ... M-I-T-A ...M-I-T-A." Again the signal rose and fell.

  * * * * *

  Jim reached for the sending key and pounded out his acknowledgement:"K; M-E-R ... K; M-E-R ... K; M-E-R." He listened again, heard Venusanswer, and Jupiter. Across five hundred million miles of space ITAmen were responding to the roll-call of Earth. A reminiscent smilecrossed Jim's face as he recognized the stuttering fist of RadePerrin, on Eros. Rade always sent as if he were afraid the instrumentwould snap at his fingers.

  M-I-T-A was signalling again, and now came the message: "S-W-A. Alltrading posts, mines and colonies are warned to prepare for possibleattack. The Earth Government has just announced the receipt of anultimatum from--" A raucous howl cut across the message and drowned itout. The siren blast howled on and on, mocking Jim's straining ears."Well I'll be--Interference! Deliberate blanketing! The rats! The--"He blazed into a torrent of profanity whose imaginativeness wasmatched only by its virulence.

  Mac was clutching his shoulder, stirred for once out of his vaunted"deegnity." "What is it, mon, what is it?"

  "War, you bloody Scotchman, war! That's what it is!"

  "War! Foosh, man, 'tis eempossible!"

  "The hell it's impossible! Damn, and Darl not here! Take over, Mac;I've got to go up an' get him!"

  * * * * *

  In the meantime Thomas' helpless journey had come to an end. After aninterminable descent in what to him had been pitch darkness, the giantwho was carrying him halted. Darl had heard the whistling inrush ofair into some lock, then the clanging of a door. He felt himselfhurled to the ground. Fumbling hands tugged at him, drew off his spacesuit.

  The dim light of the cavern, as the helmet was dragged from his head,hurt Darl's eyes. Salt sweat stung them. It was hot, hotter than theDome, hot as it was in the surta mine, where only the nervelessVenusians could work for any length of time.

  Darl struggled to focus his eyes on a blurred blue form that toweredabove him. He felt sharp claws scratch at him and realized that cordswere being passed around his limp body. They cut tightly into his legsand his arms. Then he was staring at a tube in the hand of his captor.Its end glowed with a brilliant purple light, and he felt a flood ofreawakened energy warm him. His head jerked up, he strained againstthe taut, strong fibers binding him. The paralysis was gone, but hewas still helpless.

  A husky, rumbling voice broke the silence. "I wouldn't struggle,Earthman, if I were you. Even should you get free I still have myray-tube. And my little friends would ask nothing better than yourbody to play with."

  Darl writhed to a sitting posture. Now he could see his mysteriousabductor clearly. This eight-foot, blue-feathered individual, withcurved beak and beady eyes glittering from his naked, repulsivelywrinkled head, was a Martian! Despite the human shape of his body,despite his jointed limbs and thumbed hands, this denizen of the redplanet resembled a vulture far more than he did any other Earthcreature.

  * * * * *

  The Earthman's pride of race came to his rescue. "What's the game?" hegrowled. "Looking for trouble?" There was nothing in Darl's voice toshow the fear that chilled him. Behind the Martian he could seevaguely a group of little yellow Mercurians.

  "I'll ask all the questions here. And you'll answer them, too, ifyou're wise. Even your dull mind should comprehend that you are in mypower."

  Darl decided to proceed more cautiously. "What do you want from me?"he asked.

  "I want," the Martian answered, "the recognition signal of Earth'sspace-ships."

  "What!" The ejaculation burst from Darl's throat. This alien wantedthe secret code, the watch-word that distinguished Earth's spaceships, that gained for them free admittance to ITA's armed posts onthe outer planets! This could mean only one thing, that the longrivalry, the ancient dispute between Earth and Mars was about to flareinto open war. Any friendly visit from a foreign flier would beheralded by word from M-I-T-A. Thomas' face became a stony mask,covering the tumult of his mind.

  "You understood. I want the Earth recognition signal at once--andafter that, the surrender of the Dome." The very calmness of the huskytones was a threat.

  "Never!"

  "I warn you, Darl Thomas. It would be the better part of wisdom foryou to yield willingly what I ask. You will give in eventually, andthe means of persuasion I shall use will not be exactly--pleasant."

  "You'll get nothing from me!"

  The outlander's lidless eyes were filmed with a gray membrane. Hishead thrust forward, the feathered ruff beneath it bristled. Darlbraced himself to withstand the swooping pounce that seemed imminent,the slash of the sharp beak. A burring rattle broke the momentaryhush. The Martian relaxed, turned to the Mercurian from whom the soundhad come and replied with staccato vibrance.

  * * * * *

  As the cave filled with a whirring tumult Darl had a chance to examinethe Mercurian natives crowding around his prostrate body. They werelittle yellow midgets, ranging from eighteen inches to two feet inheight. Half of their small stature was taken up by snouted heads,with saucer-like, crimson eyes, and long white tusks jutting fromfoam-flecked mouths. The trunks were globular. The spindling legs andthin arms ended in sharp claws. There was an impression of animalferocity about these tiny beings that stamped them as utter savages.

  His captor was speaking to the Earthman again, his horny beak partedin what might have been a grim smile. "My friends remind me that Ipromised you to them. They have not forgotten how you and your fellowsdrove them from their burrows."

  Darl was suddenly cold, though the sweat still streamed from his boundbody. An uncontrollable shudder took him as he saw what the diminutiveclaws of the midgets held. While the Dome was still an unfinishedframework one of the Terrestrian artisans had somehow been isolatedfrom his fellows. Thomas had been of the party that found what wasleft of him, and the memory was still a throbbing nightmare.

  "Once more! Will you give me the recognition signal?"

  Darl shook his head, and prayed for sudden death. The Martian spoke tothe dwarfs. They started forward, saliva drooling from their tusks.Darl gritted his teeth. He would hold out as long as was humanlypossible.

  A shrill rhythmic whistle came from somewhere outside. The blue giantstarted and snapped something to the Mercurians. Then he turned toDarl. "I must leave you for a little while," he said. "You have tillI return to change your mind."
With a parting admonition to thesavages he was gone through a side door that Thomas had not noticedbefore.

  * * * * *

  Grateful for the postponement, however short, of the inescapableordeal, Darl took stock of his situation. He lay, firmly bound, on thegritty rock floor of a low-ceiled cave about twelve feet square. Inone wall was a door of red metal. The portal through which the Martianhad vanished was next to it. Darl repressed an exclamation when he sawthe opposite wall. It was of solid metal, bluishly iridescent. Thatwas beryllium steel, the alloy from which the barriers at theterminals of the surta mine were fashioned. He forced his head higher.There were the