was he certain he
could wrestle Ashe down in a real fight.

"That globe-ship was never built on this world. Use your head, Murdock.
Think about your furry-faced friend and the baldy with him. Did either
look like normal Terrans to you?"

"But--a spaceship!" It was something that had so long been laughed to
scorn. When men had failed to break into space after the initial
excitement of the satellite launchings, space flight had become a matter
for jeers. On the other hand, there was the evidence collected by his
own eyes and ears, his own experience. The services of the lifeboat had
been techniques outside of his experience.

"This was insinuated once"--Ashe was lying flat now, gazing
speculatively up at the projection of logs and earth which made them a
partial roof--"along with a lot of other bright ideas, by a gentleman
named Charles Fort, who took a lot of pleasure in pricking what he
considered to be vastly over-inflated scientific pomposity. He gathered
together four book loads of reported incidents of unexplainable
happenings which he dared the scientists of his day to explain. And one
of his bright suggestions was that such phenomena as the vast artificial
earthworks found in Ohio and Indiana were originally thrown up by space
castaways to serve as S O S signals. An intriguing idea, and now perhaps
we may prove it true."

"But if such spaceships were wrecked on this world, I still don't see
why we didn't find traces of them in our own time."

"Because that wreck you explored was bedded in a glacial era. Do you
have any idea how long ago that was, counting from our own time? There
were at least three glacial periods--and we don't know in which one the
Reds went visiting. That age began about a million years before we were
born, and the last of the ice ebbed out of New York State some
thirty-eight thousand years ago, boy. That was the early Stone Age,
reckoning it by the scale of human development, with an extremely thin
population of the first real types of man clinging to a few warmer
fringes of wilderness.

"Climatic changes, geographical changes, all altered the face of our
continents. There was a sea in Kansas; England was part of Europe. So,
even though as many as fifty such ships were lost here, they could all
have been ground to bits by the ice flow, buried miles deep in quakes,
or rusted away generations before the first really intelligent man
arrived to wonder at them. Certainly there couldn't be t