'But what is the signification, sir?' I asked, rising from my chair and stepping close.
'Ah! You improve, soldier. It hath signification, not use: and it signifies the motion of the heavens. See—this larger ball is the sun; and here, on their several rods, the planets—all swinging in their courses. By a pointer on this dial-plate—observe me now—I reduce the space of a day to one, two, three minutes, as I chose, retarding or accelerating, but always in just proportion. 'Tis set for these December days; you will remark the sun's ambit—how it lies south of the zenith, and how far short it rises and falls from the equinoctial points. But wait awhile, and in a few minutes—that is to say, days—you shall see him start to widen his circuit. Here now is Saturn, with his rim: and here Venus—mark how delicately she lifts, following the motion of her lord—`
'Just with the Sun her dainty feet doth move—'
'And this is Dancing—Orchestra Coeli—the Dancing of the Firmament.'
'Wonderful!' I cried.
'You shall say so presently! So far you have only seen: now hear!'
He drew out a small brass pin from the foot of the mechanism, and at once it began to hum, on three or four notes such as children make with a comb and a scrap of paper.
The notes lifted and fell, and the little balls—each in his separate circle—wheeled and spun, twinkling in time with them, until my head, too, began to swim.
'It will run for an hour now,' my host assured me. 'Indeed, with one to watch and draw up the weights at due intervals, it will run for ever.'
'It dizzies me,' said I.