“It seems to me,” rejoined Leacraft, “that they tell us nothing of the sort. It is a mild madness to misconstrue them so completely. These extremes of temperatures are far lower than any we have observed, and yet we have been expelled from Scotland. It is the snow. These endless heaping torrents from the skies that have driven us out, and they—I do believe it—will continue; but it has no parallel. Nothing warned us of this—and as to our climatic safety, it was as fixed as the change of day to night when, without warning, without precedent, a bridge of mountains tumbles into a hole in the sea, another bridge rises as a dam, and either occurrence seemed about as likely as that the moon would fall into the sun. I think indeed the advantage of a guess might have lain with the latter supposition.”
“Well. The snow; you say it will continue,” said Sir John with a sudden reflex action of revolt. “Why will it continue?”
“I estimate the probability for that in this way,” answered Leacraft. “The atmosphere is a system of balances never at rest, unless in equilibrium, and never in equilibrium except at rare intervals, and then in limited and favored spots. This state of inequilibrium causes constant motion, currents, storms, winds and precipitation, whether of rain or snow, depending on temperature and position. Now the motor power of the movement in all this atmospheric mass is difference of temperature, the hot air rising and flowing to the poles, and the cold air of the poles descending and flowing to the equator. That is the A. B. C. of meteorological physics. But the revolution of the earth causes the cold polar winds to blow from the northeast and the warm equatorial winds to blow from the southwest, that is with reference to our position in the northern hemisphere. Now if we are undergoing a progressive refrigeration, the contrast in temperatures between our latitude and the temperature of the equator increases, and because of that, the velocity of the wind blowing from the latter increases too, and the moisture that these winds would have dropped over the equatorial zones is carried further north, and our annual precipitation is thereby increased—our snow falls become more continuous and thicker. Think what the removal of the Gulf Stream means. Croll has clearly shown that the heat bearing capacity of the Gulf Stream is enormous. It seems incredible. I recall some of his statements. He says that the Gulf Stream conveys as much heat as is received from the sun by over one million and a half square miles at the equator, and the amount thus conveyed is equal to all the heat which falls upon the globe within thirty-two miles on each side of the equator; further that the quantity of heat conveyed by the Gulf Stream in one year is equal to the heat which falls, on an average, on three millions and a half square miles of the arctic regions, and that there is actually therefore nearly one-half as much heat transferred from tropical regions by the Gulf Stream as is received from the sun by the entire Arctic regions, the quantity conveyed from the tropics by the stream to that received from the sun by the Arctic regions being nearly as two to five. And it is this fact of the tremendous drain that the Gulf Stream makes on the equatorial regions, those immense manufactories of heat, that its removal—meaning the sudden abstraction of this heat or much of it from our latitude—produces a more forceful interchange in the airs of the north and the south. It produces winds of a higher velocity, and because of this, the wind coming to us from the Equator does not so quickly free itself of its contained moisture. Croll has shown in his splendid work of theory and proof, that the winds warmed by the Gulf stream are the true causes for our unusual and exceptional heat above corresponding positions on the western side of the Atlantic basin. The Gulf Stream gone, these warming winds will bring us heat no longer. But they will bring us moisture, and in larger quantities, and then the process of refrigeration over our chilled coasts will turn that into snow. The snows will be deeper, and they will last longer. In this way, Croll, defending himself against the criticism of Findlay, shows that the winds—the anti-trades blowing from the south to replace the atmospheric emptiness—I suppose we might say vacuum—left by the descent of the cold winds from the poles, parted with the most of their moisture in the equatorial belt. Now by reason of their greater velocity they will not do that; they will reach us much less despoiled of their watery burdens.
“Our highlands and our coast position make us natural condensers. To-day we have a rainfall in the year of about thirty inches. That may now be doubled. The southwest winds are our most general winds. Out of a thousand as a maximum, during the year, two hundred and twenty-five are from the southwest. These are wet winds. And in the same total there are one hundred and eleven south winds which also carry moisture, making a possible percentage of one third of all the winds that blow over us as rain winds, or now by reason of our altered state as snow makers. But this relative frequency will now be increased. There will be a longer continuation of the west winds, because as I have suggested they will be stronger. They are to-day most intense in the winter months. Our south and southwest winds gather moisture from a wide expanse of sea, the same expanse from which they formerly gathered heat from the Gulf Stream was widely diffused over the north Atlantic, both north and south, for as Croll shows, by reason of a high barometric pressure somewhere off the west of Maderia and a low pressure north of Iceland, the tendency of the air south of the English Isles at that point is to flow north. But these winds are no longer heat carriers. They bring moisture only. They bear to us through the air the winding sheets of our burial.”
The two men looked at each other, and it was a look of anguish. The sudden cruel dreadfulness, the hideous mutation which might send the English people out of their land on the strange quest for a new home crushed them into an emotional inanition. They did not seem to exist. Their lips lost their color, and only the paralysis of stupor saved them from breaking down into sobs.
It was a few moments later that Leacraft spoke. He asked, “And the people of Glasgow. How did they get away?”
Sir John Clarke scarcely raised his head and his words scarcely formed an articulate whisper; “They went by steamers.”
CHAPTER VII.
IN LONDON, FEBRUARY, 1910.
In the smoking room of the Bothwell Club, on Cheapside, back of St. Paul’s, London, on February 12th, in the year of grace, 1910, two men sat in attitudes of earnest attention. A third man older than either with his back to a blazing fire, whose simulated effect of comfort arose from the curling tendrills of gas flames that swept over another simulation of heaped up logs, was speaking with desperate emphasis. He seldom looked at his arrested auditors, nor indeed moved, except when he raised his head, and his eyes, strained with a hopeless longing, sought the gay frescoes of the ceiling, or when, in pauses of his declamations, he walked to a window and raising the curtain looked out upon the city, up to the dome of St. Paul’s, which rose like an Irkutsk igloo above a plain of snow.