Then for weeks Grand Fleet drilled, maneuvered, and practiced. All space within ten parsecs of Arisia was divided into minute cubes, each of which was given a reference number. Fleets were so placed that any point in that space could be reached by at least one fleet in thirty seconds or less of elapsed time.
Drill went on until, finally, it happened. Constance, on guard at the moment, perceived the slight "curdling" of space which presages the appearance of the terminus of a hyperspatial tube and gave the alarm. Kit, the girls, and all the Arisians responded instantly—all knew that this was to be a thing which not even the Five could handle unaided.
Not one, or a hundred, or a thousand, but at least two hundred thousand of those tubes erupted, practically at once. Kit could alert and instruct ten Rigellian operators every second, and so could each of his sisters; but since every tube within striking distance of Arisia had to be guarded or plugged within thirty seconds of its appearance, and since all of the work was done out in space and not in the tank, it is seen that the Arisians did practically all of the spotting and placing during those first literally incredible two or three minutes.
If the Boskonians could have emerged from a tube's terminus in the moment of its appearance, it is quite probable that nothing could have saved Arisia. As it was, however, the enemy required seconds, or sometimes even whole minutes, to traverse their tubes, which gave the defenders much valuable time.
One of the observers—an Arisian or a Third-Stage Lensman—at first perception of a terminus erupting, noted the number of the threatened space-cubicle, informed the Rigellian operator upon whose panel the number was, and flashed a message to all other observers that that number had been "handled." The observer flashed the number to the Communications board of the flagship of the fleet covering that space; a flash which was automatically relayed to every Communications and Navigations officer of that fleet, and which also automatically called upon Reserve for another fleet to take the place being vacated. Without further orders, the fleet drove toward its target cube. En route, tube-locators mapped the terminus and marked its exact location upon each vessel's tube plates.
Upon arriving, the fleet englobed the terminus and laced itself, by means of tractors and pressors, into a rigid although inertialess structure. Then, if there was time, and because the theory was that the pirates would probably send a negasphere through first, with an intrinsic velocity aimed at Arisia, a suitably equipped loose planet was tossed into "this end" of the tube. Since they might send a loose or an armed planet through first, however, the Fleet Admiral usually threw a negasphere in, too.
What happened when planet met negasphere, in the unknown medium which makes up the "interior" of a hyperspatial tube, is not and probably never will be surely known. Several highly abstruse mathematical treatises and many volumes of rather gruesome fiction have been written upon the subject—none of which, however, has any bearing here.