"I don't know. I ... simply ... do ... not ... know." Adams lost himself in thought for over a minute. "This is all _so_ new ... I know _so_ little ... and am working with such _pitifully_ inadequate instrumentation--However, we have months of time yet, and if I am unable to arrive at a conclusion before arrival--I don't mean a rigorous analysis, of course, but merely a stop-gap, empirical, pragmatic solution--we will simply remain in orbit around that sun until I do." IV. The _Procyon_ bored on through space, at one unchanging gravity of acceleration. It may not seem, at first glance, that one gravity would result in any very high velocity; but when it is maintained steadily for days and weeks and months, it builds up to a very respectable speed. Nor was there any question of power, for the _Procyon_'s atomics did not drive the ship, but merely energized the "Chaytors"--the Chaytor Effect engines that tapped the energy of the expanding universe itself. Thus, in less than six months, the _Procyon_ had attained a velocity almost half that of light. At the estimated mid-point of the flight the spaceship, still at one gravity of drive, was turned end-for-end; so that for the ensuing five-and-a-fraction months she would be slowing down. A few weeks after the turnover, Adams seemed to have more time. At least, he devoted more time to the expectant mothers, even to the point of supervising Deston and Jones in the construction of a weirdly-wired device by means of which he studied and photographed the unborn child each woman bore. He said nothing, however, until Barbara made him talk. "Listen, you egregious clam," she said, firmly, "I know darn well I've been pregnant for at _least_ seven months, and I ought to be twice this big. Our clock isn't _that_ far off; Carl said that by wave lengths or something it's only about three per cent fast. And you've been pussyfooting and hem-hawing around all this time. Now, Uncle Andy, I want the _truth_. _Are_ we in for a lot of trouble?" "Trouble? Of course not. _Certainly_ not. No trouble at all, my dear. Why, you've seen the pictures--here, look at them again ... see? Absolutely normal fetus--yours, too, Bernice. _Perfect_! No malformations of any kind." "Yes, but for what _age_?" Bernice asked, pointedly. "Four months, say? I see, I was exposed to a course in embryology myself, once." "But _that's_ the interesting part of it!" Adams enthused. "Fascinating! And, indubitably, supremely important. In fact, it may point out the key datum underlying the solution of our entire problem. If this zeta field is causing this seemingly peculiar biological effect, that gives us a tremendously powerful new tool, for certain time vectors in the generalized matrix become parameters. Thus, certain determinants, notably the all-important delta-prime-sub-mu, become manipulable by ... but you aren't _listening_!"