at least until it is stopped by the resistance of the air in the car. Consequently, now that I have a start, I need merely fold my arms, and I shall slowly but surely keep on advancing. Moreover, if I want to set to work and swim a little more, each stroke I take will increase my speed, so that by keeping on I could finally get up a speed of over a mile a minute."
It is safe to say that William could never have succeeded in obtaining so great a rapidity as this, since the resistance of the air would increase as the square of his velocity. Still, he could have obtained a high rate of speed had he had sufficient space to swim in. As it was, however, he was fast approaching the bottom of the car.
It was most amusing to find that when he stopped his exertions he still continued progressing at the same rate, while whenever he took a few strokes his speed increased and continued at the new rate. Finally he reached the lower part of the car, and catching hold of one of the handles on the lounge, he pulled himself down.
"This is hot work," said he, as he let go of the handle and remained lying about ten inches above the sofa. "It's hot work, but it's glorious fun! I wonder if I'll be able to swim up again.
