"Certainly, and for two reasons: the first is, that we are nearer the centre of the globe, which consequently attracts us more strongly, and this force of gravitation is nothing but weight; the second is, the rotary force, which is nothing at the pole, is very marked at the equator, and objects there have a tendency to fly from the earth: they are less heavy."
"What!" exclaimed Johnson, seriously; "have we not the same weight everywhere?"
"No, Johnson; according to Newton's law, bodies attract one another directly as their masses, and inversely to the square of their distances. Here I weigh more, because I am nearer the centre of attraction; and on another planet I should weigh more or less according to the mass of the planet."
"What!" said Bell, "in the moon—"
"In the moon my weight, which is two hundred pounds at Liverpool, would be only thirty-two pounds."
"And in the sun?"
"O, in the sun I should weigh more than five thousand pounds!"
"Heavens!" said Bell; "you'd need a derrick to move your legs."
"Probably," answered the doctor, laughing at Bell's amazement; "but here the difference is imperceptible, and by an equal effort of the muscles Bell would leap as high as on the docks at Liverpool."
"Yes, but in the sun?" urged Bell.