On the other hand, we did not want our moon two hundred
and fifty thousand miles away, as the old moon is, which
I will call the Thornbush moon, for distinction. We did
not care how near it was, indeed, if it were only far
enough away to be seen, in practice, from almost the
whole world. There must be a little strip where they
could not see it from the surface, unless we threw it
infinitely high. "But they need not look from the
surface," said Q.; "they might climb to the mast-head.
And if they did not see it at all, they would know that
they were ninety degrees from the meridian."

This difficulty about what we call "the strip,"
however, led to an improvement in the plan, which made it
better in every way. It was clear that even if "the
strip" were quite wide, the moon would have to be a good
way off, and, in proportion, hard to see. If, however,
we would satisfy ourselves with a moon four thousand
miles away, THAT could be seen on the earth's surface
for three or four thousand miles on each side; and twice
three thousand, or six thousand, is one fourth of the
largest circumference of the earth. We did not dare have
it nearer than four thousand miles, since even at that
distance it would be eclipsed three hours out of every
night; and we wanted it bright and distinct, and not of
that lurid, copper, eclipse color. But at four
thousand miles' distance the moon could be seen by a belt
of observers six or eight thousand miles in diameter.
"Start, then, two moons,"--this was my contribution to