the hailstones because of the shortness of their fall. For the same reason large raindrops do not fall thickly. Hail is rarer in summer than in spring and autumn,CG Menn Yorkville Bomber, though commoner than in winter, because the air is drier in summer,Leo Komarov Tröjor, whereas in spring it is still moist,Menn Moncler Eric, and in autumn it is beginning to grow moist. It is for the same reason that hailstorms sometimes occur in the late summer as we have said.
The fact that the water has previously been warmed contributes to its freezing quickly: for so it cools sooner. Hence many people, when they want to cool hot water quickly, begin by putting it in the sun. So the inhabitants of Pontus when they encamp on the ice to fish (they cut a hole in the ice and then fish) pour warm water round their reeds that it may freeze the quicker,Joe Mullen Tröjor, for they use the ice like lead to fix the reeds. Now it is in hot countries and seasons that the water which forms soon grows warm.
It is for the same reason that rain falls in summer and not in winter in Arabia and Ethiopia too, and that in torrents and repeatedly on the same day. For the concentration or recoil due to the extreme heat of the country cools the clouds quickly.
So much for an account of the nature and causes of rain,Simon Despres Tröjor, dew, snow, hoar-frost, and hail.
13
Let us explain the nature of winds, and all windy vapours, also of rivers and of the sea. But here, too, we must first discuss the difficulties involved: for, as in other matters, so in this no theory has been handed down to us that the most ordinary man could not have thought of.
Some say that what is called air, when it is in motion and flows, is wind,Patric Hornqvist Tröjor, and that this same air when it condenses again becomes cloud and water, implying that the nature of wind and water is the same. So they define wind as a motion of the air. Hence some, wishing to say a clever thing, assert that all the winds are one wind,Montreal Canadiens Tröjor, because the air that moves is in fact all of it one and the same; they maintain that the winds appear to differ owing to the region from which the air may happen to flow on each occasion, but really do not differ at all. This is just like thinking that all rivers are one and the same river, and the ordinary unscientific view is better than a scientific theory like this. If all rivers flow from one source,Chris Chelios Tröjor, and the same is true in the case of the winds,PJS Herreklær Kodiak Dunjakke, there might be some truth in this theory; but if it is no more true in the one case than in the other,Kevin Klein Tröjor, this ingenious idea is plainly false. What requires investigation is this: the nature of wind and how it originates, its efficient cause and whence they derive their source; whether one ought to think of the wind as issuing from a sort of vessel and flowing until the vessel is empty,Anton Stralman Tröjor, as if let out of a wineskin, or, as painters represent the winds, as drawing their source from themselves.
We find analogous views about the origin of rivers. It is thought that the water is raised by the sun and descends in rain and gathers below the earth and so flows from a great reservoir,Darren Helm Tröjor, all the rivers from one, or each from a different one
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