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U. O. Willingly.-(A pause.)
H. Sir, it is not easy to say what I mean; but, Sir, as I have been taught by Mr. Dillon, that it is winter in one country when it is summer in another, I thought Cyrus meant to show how large his father's empire was, by saying there was winter and summer in it at once. But Persia is not large enough for that; and so I do not understand, Sir.
U.O. Cyrus did not mean that; nor, indeed, did he know anything about it, or about many other things that are well known to you and most boys in this country. And now, really, as Cyrus could not mean that, his statement does not show the extent of the country at all, since a man who might be suffocating with heat at the foot of a mountain, would perish with cold at its top.
Mr. D. You see, Henry, your remark is a very good one; and I will write it down on the margin of my Xenophon.
U. O. Well, then; as the country is not broad enough from north to south to account for the difference of climate, we must look for some other cause. Let us look at the globe. You know that regularly we may expect places
in the same latitude to have a climate of the same warmth, and that countries become warmer as we approach the equator, and colder as we proceed to either the north or with south pole. But neither of these general prin
a mother of them with ciples is always true. As for the first, there is frequently some cause that prevents places in the same line on the globe from having the same climate. So it is generally observed, that places in America are much colder than those in the same latitude in the old world. And, as for the other rule, let us turn to Persia. You see it lies much nearer to the equator than England, therefore we are to expect to find it a much warmer country than this. And so it is, in those places where we may be supposed to find the regular climate not much altered by particular circumstances. In some parts, indeed, the climate is warmer than the natural climate would be: but generally it is colder. There is, perhaps, no part of the country in which the summer is not warmer than in England; but there are many parts in which the winter is far more severe than we ever find it. Frank. Will you please to tell us what it is
that makes a country warmer or colder than it ought to be?
U. O. There are several circumstances, any of which will make a country warmer or colder than we might expect to find it. Wood is one. All wooded countries become warmer as the woods are cleared away, the lakes are drained, and the bogs and marshes are dried up to make room for man. As these are the works of civilized men, it may be said that a country generally becomes warmer as it becomes civilized. We know, for instance, that this country and Germany are much warmer now than they formerly were. It is recorded that large armies were anciently accustomed in the winter season to cross the river Danube on the ice. The river is never frozen over now.
H. But, Sir, if this country was formerly colder, or even so cold as now, how could the people go without clothes, as they did ?
U. O. Because they were all face, as similar savages used to say by way of explanation. If all the parts of our bodies were as much exposed as our faces, they would be quite as well able to bear the cold. As there are not many countries which are more bare of trees than
Persia, this cause can have no effect there. We must therefore look to the other causes which make a climate cold-mountains and elevated land. I have already explained to you how it becomes colder as we ascend a mountain, or rather, when we mount higher into the air; for it is colder not merely as we ascend a mountain, but as we get higher, in any way, above the level of the ocean. Thus people who go up into the air in balloons find that it gets colder the higher they ascend. So, not only a mountain, but a plain is colder in proportion to its height; but they are not cold in the same proportion ; for if there be an extensive level land 8000 feet above the level of the ocean, that land will be cold indeed, but not so cold as a mountain of the same height in the same latitude.
There is, perhaps, no part of the world in which the difference caused by the different height of the ground is so striking as in South America. For instance, the valley of Quito, in Peru, and the city of Mexico (pointing to the places in the map of the world) are situated in the warmest region of the globe; but being placed on lofty plains, they generally enjoy the climate of perpetual spring, while above them they see the mountain-ridges covered with snow, which remains on some of the summits nearly throughout the year; and while, lower down towards the sea-shore, the inhabitants are almost suffocated by the intense and often sickly heat. But, Mr. Dillon, I ought to leave you to explain these matters, which you understand much better than I do.
(Mr. Dillon bowed, and, after a pause, proceeded.)
Besides the things which influence the climate, as explained by Mr. Oldcastle, a great deal depends on the soil itself. Grassy meadowlands occasion a much cooler temperature than where the earth is bare, and the dry sands of the desert produce a still greater degree of heat than that. The climate of a country, as it regards heat and cold, also very much depends upon the circumstances whether the winds that most prevail come from or pass over the warm or cold regions of the world. If a country in this hemisphere happens from its situation to be much exposed to the winds which blow from the cold north, it will be colder than another country, in the same latitude, which has a larger