afternoon last week!" He cursed luridly. "Why couldn't that
blasted magazine say _what_ afternoon? I've gone over a lot of
twentieth century copies of that magazine; that expression was a
regular cliche with them."

Loudons looked over his shoulder at the photostated magazine page.

"Well, we know it was between June thirteen and nineteen, inclusive,"
he said. "And there's a picture of the university president, complete
with gold-plated spade, breaking ground. Call it Wednesday, the
sixteenth. Over there's the tip of the shadow of the old Cathedral of
Learning, about a hundred yards away. There are so many inexactitudes
that one'll probably cancel out another."

"That's so, and it's also pretty futile getting angry at somebody
who's been dead two hundred years, but why couldn't they say
Wednesday, or Monday, or Saturday, or whatever?" He checked back in
the astronomical handbook, and the photostated pages of the old
almanac, and looked over his calculations. "All right, here's the
angle of the shadow, and the compass-bearing. I had a look, yesterday,
when I was taking the local citizenry on that junket. The old baseball
diamond at Forbes Field is plainly visible, and I located the ruins of
the Cathedral of Learning from that. Here's the above-sea-level
altitude of the top of the tower. After you've landed us, go up to
this altitude--use the barometric altimeter, not the radar--and hold
position."

Loudons leaned forward from the desk to the contraption Altamont had
rigged in the nose of the helicopter--one of the telescope-sighted
hunting rifles clamped in a vise, with a compass and a spirit-level
under it.

"Rifle's pointing downward at the correct angle now?" he asked. "Good.
Then all I have to do is hold the helicopter steady, keep it at the
right altitude, level, and pointed in the right direction, and watch
through the sight while you move the flag around, and direct you by
radio. Why wasn't I born quintuplets?"

"Mr. Altamont! Dr. Loudons!" a voice outside the helicopter called.
"Are you ready for us, now?"

Altamont went to the open door and looked out. The old Toon Leader,
the Reader, Toon Sarge Hughes, his son, and four young men in
buckskins with slung rifles, were standing outside.

"I have decided," the Tenant said, "that Mr. Rawson and Sarge Hughes
and I would be of more help than an equal number of younger men. We
may not be as active, but we know the old ruins better, especially the
paths and h