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Old Tiney, surliest of his kind,
Who, nursed with tender care, And to domestic bounds confined,
Was still a wild jack hare.
Though duly from my hand he took
His pittance every night, He did it with a jealous look,
And, when he could, would bite.
His diet was of wheaten bread,
And milk, and oats, and straw; Thistles, or lettuces instead,
With sand to scour his maw.
On twigs of hawthorn he regaled,
On pippin's russet peel,
Sliced carrot pleased him well.
A Turkey carpet was his lawn,
Whereon he loved to bound, To skip and gambol like a fawn,
And swing himself around.
His frisking was at evening hours,
For then he lost his fear;
Or when a storm drew near.
Eight years and five round rolling moons
He thus saw steal away, Dozing out all his idle noons,
And every night at play.
I kept him for his humour's sake,
For he would oft beguile
And force me to a smile.
But now beneath this walnut shade
He finds his long, last home,
Till gentler Puss shall come.
She, still more aged, feels the shocks
From which no care can save,
Must soon partake his grave.—Cowper.
LESSON LXIV. THE SNOW LINE.
The high peak glistened before us, and the sun's rays falling upon it caused it to appear of a beautiful colour—a mixture of gold and red; as though a shower of roses had fallen upon the snow! We noticed that there was now more snow upon the mountain than when we had first seen it, and that it came farther down its sides. This attracted the attention of all of us; and Frank at once called for an explanation, which his mother volunteered to give, for she very well understood the phenomenon.
"In the first place," she said, " as you ascend upwards in the atmosphere, it becomes thinner and colder. Beyond a certain point it is so cold, that neither men nor animals exist. This can be proved in several ways, and the experience of those who have climbed mountains, only three miles high, confirms it. Some of these adventurous men have been nearly frozen to death. This is a fact, then, in regard to the atmosphere over all parts of the earth; but we may also observe, that under the equator you may go higher, without reaching this extreme cold, than in the countries which lie nearer to the poles. Another fact, which you will easily believe, is, that in summer you can climb higher before you reach the cold region than in winter. Bear these facts in mind. Now, then, if it be so cold at a certain height that men would be frozen to death, of course at that height snow will not melt. What is the natural inference? Why—that mountains whose tops pierce up into this cold region will most certainly be covered with perpetual snow. It is not likely that anything but snow ever falls upon their summits,—for when it rains upon the plains around them, it is snowing upon the high peaks above. Indeed it is probable that most of the rain which descends upon the earth has been crystals of snow when it commenced its descent; and afterwards melting in the lower and warmer regions of the atmosphere, takes the shape of water globules, and thus falls to the ground. These globules, no doubt, are very small when they first emerge from the snow region; but as they pass slowly downward through clouds of vapour, they gather together and attract others (by a law which I have not time to explain); and, descending faster and faster, at length plash down to the earth in large drops. Whenever it rains, then, at any particular place, you may be almost certain that it is snowing at the same time over that place—only at a point in the atmosphere far above it. I have been convinced of this fact, by observing that immediately after every occasion when it has rained in the valley, there appeared a greater
quantity of snow upon the mountain. Had the mountain not been there, this snow would have continued on and become rain, like that which fell upon the plains and into the valley."
"Then, mamma," interrupted Frank, "this mountain must be of great height since the snow lies upon it all the year.'
"Does that follow?"
"I think so. You said the snow did not melt because it was cold high up."
"But suppose you were in a country near the North Pole, where snow lies all the year at the very seaside, and consequently at the sea level, would it then prove a mountain to be very high?"
"Oh ! I see—I see now. The perpetual snow on a mountain only shows it to be of great height when the mountain happens to be in warm latitudes."
"Precisely so. In very warm countries, such as those within the tropics, when you see the snow cap upon a mountain, you may infer that it is a very high one—at least over two miles in height; and when there is much snow upon it—that is, when the snow reaches far down its sides—it proves the mountain to be still higher—three miles or more above the level of the ocean."
"Our mountain, then, must be a high one, since it is in a warm latitude, and snow lies all the year upon it."
"It is a high one, comparatively speaking; but you will remember, when we first saw it, there was only a small patch of snow upon its top, and probably in very hot summers that disappears altogether; so that it is not so high as others in South America. Taking our latitude into calculation, and the quantity of snow ■which lies upon this mountain, I should say it was about 14,000 feet."
"Oh! so much as that! It does not seem half so high. I have seen mountains that appeared to me to be quite as high as it, and yet it was said they did not measure the half of 14,000 feet."
"That arises from the fact that you are not viewing this one from the the sea level, as you did them. The plain upon which it stands, and from which we view it, is of itself elevated nearly half as much. You must remember that we are upon one of the high tables of the American continent."
Here, for a minute or so, the conversation stopped, and we travelled on in silence, all of us with our eyes fixed on the white and roseate peak that glittered before us, leading our eyes far up into the heavens.
Frank again resumed the discourse which had been broken off by our admiration of this beautiful object,
"Is it not curious," said he, "that the snow should lie so regularly coming down on all sides to the same height, and ending just like the cape of a coat, or the hem of a nightcap? It seems to be a straight line all round the mountain."
"That line," rejoined his mother, "is, as you say, a curious phenomenon, and caused by the laws of heat and cold, which we have just been explaining. It is called the ' snow line,' and a good deal of speculation has arisen among cosmographers about the elevation of this line. Of course, on mountains within the tropics this line will be at a great height above the level of the sea. As you advance northward or southward to the Poles, it will be found lower and lower, until within the frigid zones it may be said to cease altogether—for there, as we have