Free To the Galactic Rim: The John Grimes Saga by A. Bertram Chandler Page B

But they’ve found other ships when they’ve wanted to. They’ve never used the old pirate’s technique of lying in wait at breaking-out points. A Mass Proximity Indicator? Could be. It’s theoretically possible. It could be for a ship under Mannschenn Drive what radar is for a ship in normal space-time. Or some means of homing on a temporal precession field? That’s more like it, I think, as this vessel was able to escape when she went random.
    “But if they want us—and they will—they’ll find us. And then”—he looked at Grimes, his blue gaze intense—“and then it’s up to you, Ensign.”
    “To all of us,” said Grimes.

13

    SHE WAS UNDERMANNED, this Epsilon Sextans, but she functioned quite efficiently. Craven kept a Control Room watch himself, and the other two watchkeepers were Grimes and Jane Pentecost. Four on and eight off were their hours of duty— but there was plenty of work to be done in the off duty periods. The Captain, of course, was in over-all charge, and was trying to bring his command to the pitch of efficiency necessary for a fighting ship. Jane Pentecost was responsible for meals—although these, involving little more than the opening of cans, did not take up too much of her time. She had also taken over biochemist’s duties, but called now and again upon Grimes to help her with the ATREG unit. Its operation was simple enough, but it was inclined to be temperamental and, now and again, allowed the carbon dioxide concentration to reach a dangerous level. Grimes’ main concern was his armament. He could not indulge in a practice shot—the expulsion of mass by a ship running under interstellar drive is suicidal; even the employment of laser weapons is dangerous. But there were tests that he could make; there was, in the ship’s stores, a spare chart tank that he was able to convert to a battle simulator.
    Craven helped him, and set up targets in the tank, glowing points of light that were destroyed by the other sparks that represented Grimes’ missiles. After one such drill he said, “You seem to know your stuff, Ensign. Now, what’s your grasp of the tactical side of it?”
    Grimes considered his words before speaking. “Well, sir, we could use laser with the Drive in operation—but we haven’t got laser. The pirates have. They can synchronize and just carve us up at leisure. This time, I think they’ll go for the interstellar drive engine room first, so that we can’t get away by the use of random precession.”
    “Yes. That’s what they’ll do. That’s why I have that compartment literally sealed in a cocoon of insulation. Oh, I know it’s not effective, but it will give us a second or so of grace. No more.”
    “We can’t use our reflective vapor,” went on Grimes. “That’d be almost as bad, from our viewpoint, as loosing off a salvo of missiles. But, sir, when this ship was first attacked there must have been a considerable loss of mass when the atmosphere was expelled through the rents in the shell plating . . . the Drive was running. How was it that the ship wasn’t flung into some other space-time?”
    “Come, come, Mr. Grimes. You should know the answer to that one. She was held by the powerful temporal precession fields of the drive units of the two pirates. And then, of course, when the engineers managed to set up their random precession there was no mass left to be expelled.”
    “H’m. I see. Or I think I see. Then, in that case, why shouldn’t I use my ALGE as soon as we’re attacked?”
    “No. Better not. Something might just go wrong—and I don’t want to become one of my own ancestors.”
    “Then . . . ?”
    “You tell me, Mr. Grimes.”
    “Cut our Drive . . . ? Break out into the normal continuum? Yes . . . it could work.” He was becoming enthusiastic. “And then we shall be waiting for them, with our missile batteries, when they break out.”
    “We’ll make an admiral of you yet, young Grimes.”

    With watchkeeping and with