distance to the earth or any other planet whose size and force of
gravity are known. The same formula, taken in the opposite sense, of
course, shows how fast a body must start from a planet in order that it
may be freed from its control. The formula is V = square root of (2
gr.), in which "g" is the acceleration of gravity, equal for the earth
to 32 feet in a second, and "r" is the radius of the attracting body. On
Menippe I knew "g" must equal about one twentieth of a foot, and "r"
31,680 feet. Like a flash I applied the formula while the giant's
muscles were yet tightening for the kick: 31,680 × 1/20 × 2 = 3,168, the
square root of which is a fraction more than 56. Fifty-six feet in a
second, then, was the critical velocity with which I must be kicked off
in order that I might never return. I perceived at once that the giant
would be able to accomplish it. I turned and shouted up at him:

"Hold on, I have something to say to you!"

I dimly saw his mountainous face puckered into mighty wrinkles, out of
which his eyes glared fiercely, and the next moment I was sailing into
space. I could no more have kept a balance than the earth can stand
still upon its axis. I had become a small planet myself, and, like all
planets, I rotated. Yet the motion did not dizzy me, and soon I became
intensely interested in the panorama of creation that was spread around
me. For some time, whenever my face was turned toward the little globe
of Menippe, I saw the giant, partly in profile against the sky, with his
back bent and his hands upon his knees, watching me with an occasional
approving nod of his big head. He looked so funny standing there on his
little seven-by-nine world, like a clown on a performing ball, that,
despite my terrible situation, I shook my sides with laughter. There was
no echo in the profundity of empty space.