careful, however, to first slip his foot under a strap at the bottom of the car—a necessary precaution to prevent him from rising with his load.
But the furniture would not budge.
"I guess I'll have to use my whole hand," he said, somewhat discomfited. But even with his hand he was unable to move the pile.
This was a positive surprise to William. "I thought," said he, "that, now that bodies have no weight, I ought to be able to lift the heaviest objects without any exertion whatever."
Then he recollected what the doctor had told him about mass. "Ah," said he, "I think I see what the trouble is. If the furniture were up in the air I should indeed require no force to hold it there, since it has no weight—that is to say, no tendency to fall. But in order to raise it, it will be necessary to use a certain amount of force to overcome its inertia. A very little force will suffice, if I am willing to wait long enough, and I could, if I wished, raise all the furniture with my little finger; but it would take too long, so I shall use both hands."
Here, again, our hero's reasoning was perfectly correct, but it was based on the assumption that objects in the car possessed no weight at all, and
