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as her own. Even the rights of hospitality do not always defend us from the intrusion of this folly, since Alderman E. will look at one of his guests who does not like turtle-soup, as though he were an orang-outang, or a hottentot. No proverb is more common than this, "every one to his taste," yet it is constantly forgotten in practice. Persons who are themselves enslaved by whims and oddities, can gaze with utter amazement at those who will not conform to their way. While political intolerance, or a wish to conform all opinions to one standard, is invariably considered absurd, the intolerance of social life is of constant occurrence.

Every man may find among his acquaintance, a few eccentric beings, who have ways of their own, from which nothing will induce them to deviate. Like a wheel of a clock they move with the most perfect regularity, always in the same position, and engaged in the same pursuit, at every hour of every day of their lives. This they have a right to do, if they please, but they expect others to be clock-wheels also, whose cogs and spokes shall so unite with their's, as to reduce the irregular proceedings of this intricate world to one harmonious movement. They rise at four o'clock in summer, and at five in winter, when they light their own fire;-you must do likewise. They dine at twelve you must follow their example, or never be asked at any other hour, however impossible it may be for you to comply. Should you be detained a few minutes after the time, when you have made an engagement, you will invariably find that your host has begun to feed without your assistance. These regular people retire to rest at a fixed moment, which no pleasant conversation will defer. In short they are parts of a machine, and the only way you have of being comfortable with them, is to twist and turn yourself into another part of it, so that guest and host may go round together;-or in other words, may have one way.

We would by no means under-value regularity or punctuality; they are, as one of our school-copies said, “the life and soul of business.” But extremes are bad. Neither do we find fault with persons for having peculiarities; human nature would not be bettered by being made uniform. All we plead for is, mutual forbearance. In our walk through life we must give and take; we must with courtesy and politeness, find pleasure in seeing others pleased, as well as in our own immediate gratifications.

SHORT PAPERS ON SUBJECTS CONNECTED

WITH SCIENCE.

· No. III.

In our last paper we endeavoured to explaia the fluidity and gravity of the atmosphere, we will now consider its elasticity and expansibility. The elasticity of the atmosphere is that power which it possesses of swelling out or regaining its former bulk after it has been condensed or compressed into small space, as soon as the force or pressure is removed. The expansibility of air is that power which it possesses of being rarified or enlarged by heat, so as to occupy a larger space than it previously did.

If a small quantity of air be enclosed in a bladder, and thie bladder thus partly filled be put under the receiver of an air pump, the bladder will swell out to its full size as the receiver is exhausted. Again, if a bladder partly filled be carried to the top of a high mountain, as we ascend the air swells out till it fills the bladder as in the former instance; in the first of these cases we relieve the bladder of the pressure of the circumambient air, by exhausting the receiver of the pump; in the last we diminish the pressure on the bladder by carrying it higher up the column of the atmosphere, and thereby allow the air within the bladder to expand and become as rare as that which surrounds it.

Atmospheric air may be compressed into the liquid state ; it requires for this purpose a pressure equal to 2.000 atmospheres. We have shown in a former paper that the atmospheric pressure at the earth's surface is 15lbs. on the inch, therefore15multiplied by 2,000, is equal to 30,000; that is to say, if we wish to reduce atmospheric air to a liquid state, we must press it with a force of 30,000lbs. on the square inch.

In proof of the great diminution in the elasticity of the air as we ascend from the earth's surface, it will be suffi

cient to state, that if the common balloon was filled on ascending from the earth, the gas would burst its silken envelope, long ere it had attained the ordinary elevation of these iying machines. One mode of ascertaining by direct experiment the diminished density,consists in filling a flask with air, at a given altitude, and then closing the aperture till the experimentor arrives at the earth's surface; the aperture is afterwards opened under water, and the difference between the air above and below is indicated by the quantity of water which enters.

In every part of the earth there is a certain elevation in the atmosphere, different according to the proximity to the equator, at which the thermometer never rises above the freezing point;—and this limit is called the level of perpetual congelation. In Norway it is at 5,000 feet above the level of the sea; in Switzerland at 6,500; in Spain and Italy at 7,000; farther south, at Teneriffe, at 9,000; directly under the sun, as in central Africa, and among the Andes in America, it is about 14,000. It follows that the same low temperature may be found at the equator as at the poles, by rising to find it, and we see why snow-capt mountains are not the tenants of high latitudes only; it is this truth which renders many parts of the tropical regions of the earth not only tolerable abodes, but as suitable as any on its surface. Much of the central land of America, near the tropics, is so raised, that, as to agreeable temperature, it rivals an European climate. The vast expanse of table-land forming the empire of Mexico, is of this kind, enjoying the immediate proximity of the sun, and yet by its elevation of 7,000 feet above the level of the ocean, possessing the most healthful fresliness. The land in many parts has the fertility of a cultivated garden, and can produce naturally most of the treasures of vegetation, found scattered over the diversified face of the earth. Some persons 'might be surprised to find the air blowing down from snow clad mountains still warm and temperate; the cause is, that there is just as much heat combined with an ounce of air on the mountain top as at its base, but above, the heat is diffused through a space perhaps twice as large as when below, therefore it is less sensible. The same measure of air which sweeps over a warm plain, at the side of a mountain, may rise and freeze water on the summit of the mountain, and , in an hour after may be among the flowers of another valley, as a gentle and warm breeze.

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