"Why, that's wonderful!" the Reader exclaimed, when he explained. "You can talk directly; how much better than just sending a telegram!" "But, finding the crypt by the shadow; that's exactly like the--" Murray Hughes began, then stopped short. Immediately, he began talking loudly about the rifle that was to be used as a surveying transit, comparing it with the ones in the big first-floor room at the Aitch-Cue House. * * * * * Locating the point on which the shadow of the old Cathedral of Learning had fallen proved easier than either Altamont or Loudons had expected. The towering building was now a tumbled mass of slagged rubble, but it was quite possible to determine its original center, and with the old data from the excellent reference library at Fort Ridgeway, its height above sea level was known. After a little jockeying, the helicopter came to a hovering stop, and the slanting barrel of the rifle in the vise pointed downward along the line of the shadow that had been cast on that afternoon in June, 1993, the cross hairs of the scope-sight centered almost exactly on the spot Altamont had estimated on the map. While he peered through the sight, Loudons brought the helicopter slanting down to land on the sheet of fused glass that had once been a grassy campus. "Well, this is probably it," Altamont said. "We didn't have to bother fussing around with that flag, after all. That hump, over there, looks as though it had been a small building, and there's nothing corresponding to it on the city map. That may be the bunker over the stair-head to the crypt." [Illustration: ] They began unloading equipment--a small portable nuclear-electric conversion unit, a powerful solenoid-hammer, crowbars and intrenching tools, tins of blasting-plastic. They took out the two hunting rifles, and the auto-carbines, and Altamont showed the young men of Murray Hughes' detail how to use them. "If you'll pardon me, sir," the Tenant said to Altamont, "I think it would be a good idea if your companion went up in the flying machine and circled around over us, to keep watch for Scowrers. There are quite a few of them, particularly farther up the rivers, to the east, where the damage was not so great and they can find cellars and shelters and buildings to live in." "Good idea; that way, we won't have to put out guards," Altamont said. "From the looks of this, we'll need everybody to help dig into that thing. Hand out one of the portable radios, Jim, and go up to about a thousand feet. If you see anything suspicious, give us a yell, and then spray it with bullets, and find out what it is afterward."