LITMIR.BIZ

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      Snow, which, in its crystallization, surpasses the most perfect gems, is invariably found arranged in determinate angles, to wit, 60°, and its double, 120°, and formed of six-sided prisms. More than one hundred kinds have been described by Dr. Scoresby and others, and all these are combinations of the six- sided prism. The uses of snow, from its non-conducting qualities, whether as appreciated by the Esquimaux as a material for huts, or by the agriculturists of our own climate as sheltering the seed, are too well known to require any particular remarks. Strange as it may appear, the proximate cause of the formation of snow is not yet fully agreed upon by the learned.

      The connection between Sound and the atmosphere is an important one. The air is a conductor of sound, and in some conditions one of the best. A bell rung in an exhausted receiver gives no sound. In the Arctic regions ordinary conversations have been distinctly heard for the distance of a mile and a half.

      All that we have thus far said in this article bears directly, in some form or other, on another of the great features of Meteorology, one of its great objects, and an unceasing topic,–namely, Climate.

      The term Climate, in its general sense, indicates the changes and condition of the atmosphere, such as we have been considering. It has something to do with all of them; it is not entirely controlled by any. Thus, places having the same mean annual temperature often differ materially in climate. In some (we quote Mrs. Somerville) the winters are mild and the summers cool, whereas in others the extremes of heat and cold prevail.

      Climates are not found coincident with lines of latitude; they are quite as often found parallel to lines of longitude. If you connect the extreme points of the mean annual temperatures by a line passing round the earth, you have a zone, but never a true circle. The curves are longitudinal.

      Climate is dependent on temperature, winds, the elevation of land, soil, ranges of mountains, and proximity of bodies of water; and it is also the expression, if we may so term it, of the changes in the atmosphere sensibly affecting our organs. Humboldt refers it to humidity, temperature, changes in barometric pressure, calmness or agitation of the air, amount of electric force, and transparency of the sky.

      When mountains range themselves in lines of latitude across a continent, they are barriers to civilization, to the mingling of races, and the union of states. Thus, the Pyrenees have always kept France and Spain apart, the Alps and the Apennines have secluded Switzerland from its neighbors. In our own country, Providence has placed our great mountains on a northern and southern axis; the slopes, the direction, the prevailing winds, the facilities for transportation and travel favor no one of our northern, southern, and western States more than another.

      Climate affects vegetation and the distribution of animal life, and thus greatly modifies commerce.

      Whatever of importance is accomplished in those countries where climate has overpowered a race is best and principally done by the men of the temperate zones, who carry with them perseverance, courage, and ability, and maintain their ascendency, true to their type, while they have their life to live.

      But with our own eyes we may perceive how much climate affects agriculture. The humidity or dryness of soils, their natural or acquired heat or cold, the prevailing winds, the quantity of rain, the snows, the dews, all affect the planter of the seed and the tiller of the ground; they increase or diminish the aggregate of the products of countries, the value of their imports and exports,– -in short, their material power, their resources, their influence, their very existence.

      The climate of our own country is exceedingly variable. The transitions from heat to cold are very sudden, the range of the mercury is very great. In the North, we have almost the Arctic winters; in the South, almost the peculiarities of the tropics. Of the State of Pennsylvania it has been said, that in this respect it is a compound of all the countries in the world. Mr. Jefferson and Dr. Rush, as before observed, insisted that our climate has changed; and Williams, the historian of Vermont, contends that New England has deteriorated in its seasons, temperature, harvests, and health, since its early settlement. Our winds blow from every point of the compass, but a due north wind is very rare. Our great western lakes have a large influence on our climate. Some learned men have asserted, that, if they were land, their area being about ninety-four thousand square miles, the region would be so cold as to be scarcely inhabitable.

      Such is an outline of our subject. The science itself is by no means systematized. Many things are taken for granted which may yet be disproved. If, says Humboldt, we perceive a want of connection in the phenomena of certain sciences, we may anticipate the revelation of new facts, whose importance will probably be commensurate with the attention directed to other branches of study. What we want is a larger class of observers, and not only those who are professional persons, but those who would commune with Nature, and seek to invigorate their minds by the acquisition of new ideas, and a recourse to rich and pure sources of enjoyment.

      But more than this. It is a requirement of the present age, says the same authority, that there should be an equal appreciation of all branches of mathematical and physical science; for the material wealth and the growing prosperity of nations are principally based upon a more enlightened employment of the products and forces of Nature.

      Much attention has of late years been paid to this subject. Many distinguished men in Europe have connected their great reputations indissolubly with it, and it is absolutely true that more persons are engaged in a common effort to promote this science than any other of our time. In Paris there is a large and flourishing society where the most brilliant of its savans combine their efforts. In London, that which was established in 1850 has met with remarkable success, and a most unexpected crowd of supporters. The finest instruments, the most accurate observations, and entire uniformity of purpose have been the result. In Germany, equal zeal prevails among its naturalists. There are more than eight hundred stations throughout the world where regular observations are made, and upwards of three hundred and sixty of them are in the United States. The Smithsonian Institution has been also a wise patron of this science, by its numerous publications, its lucid directions for observing meteorological changes, and the bestowal of standard instruments in large numbers to efficient and well-placed observers. By a recent arrangement, a portion of this work is to be performed by the Patent Office.

      Observation, and accuracy in observation, are the foundation of this science. The results are compared to the leaves of a book, which will some day be arranged and bound together in one volume. The instruments in use are delicate, ingenious, and indispensable. Their history, uses, and importance would be topic enough for a separate article.

      While at the first view Meteorology may appear to occupy but a limited sphere, upon a closer examination it will be found to embrace almost all the sciences, and to be commensurate with Nature itself. It is continually influencing us, by its agencies appealing to our senses, ministering to our wants, and governing our conduct.

      Its influence upon its votaries is equally remarkable; for, as a rule, they are distinguished among the learned, their characters are in harmony with their pursuits, and they are recognized everywhere for disinterestedness, philanthropy, and public and private virtue. While Mental Philosophy, has made but little progress since the times of Plato, and the world is but little better for scholastic disputations, Natural Science has civilized man, elevated his condition, increased the circle of his exertions, and, by the development of some of its simplest principles, united the intelligent, the learned, the enterprising, and the virtuous of all nations into a recognized and a noble brotherhood.

      TREASURE-TROVE