320 THE MATHEMATICAL PRINCIPLES [BOOK II. narrow for the magnitude of the pendulous globe, and by its narrowness obstructed the motion of the water as it yielded to the oscillating globe. For when I immersed a pendulous globe, whose diameter was one inch only, the resistance was augmented nearly in a duplicate ratio of the velocity, I tried this by making a pendulum of two globes, of which the lesser and lower oscillated in the water, and the greater and higher was fastened to the thread just above the water, and, by oscillating in the air, assisted the motion of the pendulum, and continued it longer. The experiments made by this contrivance proved according to the following table. Arc descr. in first descent . .16.8. 4. 2.1.1.1 Arc descr. in last ascent . . 12 . 6 . 3 . li . J .