There seems to be a Region high in the Air over all Countries, where it is always Winter, where Frost exists continually, since in the midst of Summer on the Surface of the Earth, Ice falls often from above in the Form of Hail.
Hailstones of the great Weight we sometimes find them, did not probably acquire their Magnitude before they began to descend. The Air being 400 times rarer than Water, is unable to support it but in the Shape of Vapour, a State in which its Particles are separated. As soon as they are condensed by the Cold of the upper Regions so as to form a Drop, that Drop begins to fall. If it freezes into a Grain of Ice, that Ice descends. In descending both the Drop of Water and the Grain of Ice, are augmented by Particles of the Vapour they pass thro’ in falling, and which they condense by their Coldness and attach to themselves.
It is possible that in Summer, much of what is Rain when it arrives at the Surface of the Earth, might have been Snow when it began its Descent; but being thaw’d in passing thro’ the warm Air near that Surface, it is changed from Snow into Rain.
How immensely cold must be the original Particle of Hail, which forms the Center of the future Hailstone, since it is capable of communicating sufficient Cold, if I may so speak, to freeze all the Mass of Vapour condensed round it, and form a Lump of perhaps 6 or 8 ounces in weight!
When in Summer time the Sun is high, and long every Day above the Horizon, his Rays strike the Earth more directly and with longer Continuance than in Winter; hence the Surface is more heated, and to a greater Depth by the Effect of those Rays.
When Rain falls on the heated Earth, and soaks down into it, it carries down with it a great Part of the Heat, which by that means descends still deeper.
The Mass of Earth to the depth perhaps of 30 Feet, being thus heated to a certain degree, continues to retain its Heat for some time. Thus the first Snows that fall in the Beginning of Winter, seldom lie long on the Surface, but are soon melted and absorbed. After which the Winds that blow over the Country on which the Snows had fallen are not rendered so cold as they would have been by those Snows if they had remained. The Earth too, thus uncovered by the Snow, which would have reflected the Sun’s Rays, now absorbs them, receiving and retaining the Warmth they afford. And thus the Approach of the Severity of Winter is retarded; and the extreme degree of its Cold is not always at the time we might expect it, viz. when the Sun is at its greatest Distance, and the Days shortest, but some Time after that Period, according to the English Proverb which says,