Mr. Ticks leaned back upon the jolting seat in unbroken silence. When his colleague, who drove, hazarded a question, the only reply was a low grunt. As sleep was out of the question in that wagon, behind that horse and in those roads, was it pain or mighty thought or nebulous calculation that oppressed the wise man of the _Planet_? At about two o'clock in the morning Mr. Stalls Ticks broke his long reserve with the following remark: "If it is, it is a unique case. The phenomenon is isolated." "I hope you feel better now?" Swift had been anxious about his colleague, and had interpreted his silence as evidence of physical distress. Mr. Ticks gave an invisible shrug of his shoulders to express the contempt he felt for his own anatomy in comparison with the attainment of exact knowledge. Otherwise, heedless of the interruption, he proceeded: "It is physically impossible that a low-pressured area could have had its centre three or four hundred miles northwest of Russell." "Indeed?" replied Swift, vaguely and unsympathetically. "It must travel towards the centre of the low pressure." "Of course," assented Swift, as he would to a lunatic. Evidently that inexpressible shock had been too much for the middle-aged man. "The Gopher lake on the north, and the Buzzard mountain on the south, prevent the isothermal curve from being deflected toward the north." "Really?" said Swift. "It will be deflected to the south, young man," said Mr. Ticks, severely. "The atmospheric equilibrium can suffer no centripetal disturbance." "Well, what then?" asked Swift, a little bored. "There could be no gyrating motion of the atmosphere. There will be no aerial contest. There could be no colder stratum above the warmer layer coming from another direction. Both would flow from the south. There could be no inversion of these conditions. My friend, Russell has experienced no tornado or cyclone. And yet--" he added wistfully and thoughtfully, "and yet--" "Well, if there was no tornado, what the deuce are we going to Empiria for?" demanded Swift. He forgot himself, and gave the four-hundred-dollar horse a sharp cut with the whip, in consequence of which the animal backed them so nearly toward the place from which they started that the journey to Empiria was seriously lengthened. Mr. Ticks did not notice this delay. "--And yet?" he mused. "What is the matter, then, if it isn't wind?" asked Swift, impatiently, after he had persuaded his horse to defer the next attack of backing for a mile or so. "Is there a new variety of atmospheric disturbance? If so, it might strike us here!"