Ali’s face was black once more.  “Probably by elimination,” he said morosely.  “If we keep our feet and all the rest go down—­that’s our proof.”

“But we ought to be able to do something—­” protested Shannon.

“Just how?” Ali’s slender brows arched.  “Do you have a gallon of that Salariki brew on board you can serve out?  We don’t know what was in it.  Nor are we sure that this whole idea has any value.”

All of them had had first aid and basic preventive medicine as part of their training, but the more advanced laboratory experimentation was beyond their knowledge and skill.  Had Tau still been on his feet perhaps he could have traced that lead and brought order out of the chaos which was closing in upon the Solar Queen.  But, though they reported their suggestion to the Captain, Jellico was powerless to do anything about it.  If the four who had shared that upsetting friendship cup were immune to the doom which now overhung the ship, there was no possible way for them to discover why or how.

Ship’s time came to have little meaning.  And they were not surprised when Steen Wilcox slipped from his seat before the computer—­to be stowed away with what had become a familiar procedure.  Only Jellico withstood the contagion apart from the younger four, taking his turn at caring for the helpless men.  There was no change in their condition.  They neither roused nor grew worse as the hours and then the days sped by.  But each of those units of time in passing brought them nearer to greater danger.  Sooner or later they must make the transition out of Hyper into system space, and the jump out of warp was something not even a veteran took lightly.  Rip’s round face thinned while they watched.  Jellico was still functioning.  But if the Captain collapsed the whole responsibility for the snap-out would fall directly on Shannon.  An infinitesimal error would condemn them to almost hopeless wandering—­perhaps for ever.

Dane and Ali relieved Rip of all duty but that which kept him chained in Wilcox’s chair before the computers.  He went over and over the data of the course the Astrogator had set.  And Captain Jellico, his eyes sunk in dark pits, checked and rechecked.

When the fatal moment came Ali manned the engine room with Weeks at his elbow to tend the controls the acting-Engineer could not reach.  And Dane, having seen the sick all safely stowed in crash webbing, came up to the control cabin, riding out the transfer in Tang Ya’s place.

Rip’s voice hoarsened into a croak, calling out the data.  Dane, though he had had basic theory, was completely lost before Shannon had finished the first set of co-ordinates.  But Jellico replied, hands playing across the pilot’s board.

“Stand-by for snap-out—­” the croak went down to the engines where Ali now held Stotz’s post.

“Engines ready!” The voice came back, thinned by its journey from the Queen’s interior.