"You remember, too, how we explained the growing altitude of the sun in the heavens which culminated on the great day of the Festival, by supposing that the axis of the planet swayed to and from the sun so as to tilt each pole towards the sun, and the other from it, alternately, thus producing what by courtesy we may call the seasons in Womla?" "Yes." "Well, judging from the observations I have made, we were probably right so far; but if you recollect, I accounted for the mysterious daily rise and set of the sun, if I may use the words, by changes in the density of the atmosphere bending the solar rays, and making the disk appear to rise and sink periodically, though in reality it does nothing of the kind. A similar effect is well-known on the earth. It produces the 'after glow' on the peaks of the Alps when the sun is far below the horizon; it sometimes makes the sun bob up and down again after sunset, and it has been known to make the sun show in the Arctic regions three weeks before the proper time. I had some difficulty in understanding how the effect could take place so regularly." "I think you ascribed it to the interaction of the solar heat and the evaporation from the surface." "Quite so. I assumed that when the sun is low the vapours above the edge of the crater and elsewhere cool and condense, thus bending the rays and seeming to lift the sun higher; but after a time the rays heat and rarefy the vapours, thus lowering the sun again. It seemed a plausible hypothesis and satisfied me for a time, but still not altogether, and now I believe I have made a discovery." "And it is?" "That Venus is a wobbler." "A wobbler?" "That she wobbles--that she doesn't keep steady--swings from side to side. You have seen a top, how stiff and erect it is when it is spinning fast, and how it wobbles when it is spinning slow, just before it falls. Well, I think something of the kind is going on with Venus. The earth may be compared to a top that is whirling fast, and Venus to one that has slowed down. She is less able than the earth to resist the disturbing attraction of the sun on the inequalities of her figure, and therefore she wobbles. In addition to the slow swinging of her axis which produces her 'seasons,' she has a quicker nodding, which gives rise to day and night in some favoured spots like Womla." "After all," said I, "tis a feminine trait. _Souvent femme varie._" "Oh, she is constant to her lord the sun," rejoined Gazen. "She never turns her back upon him, but if I have not discovered a mare's nest, which is very likely, she becks and bows to him a good deal, and thus maintains her 'infinite variety.'" The cloudy surface of Mercury now lay far beneath us, and the glowing disc of the sun, which appeared four or five times larger than it does on the earth, had taken a bluish tinge--a proof that we had reached a very great altitude.