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their shores, may sometimes, indeed, provide them with a tree, a mast, or spar; but these materials are too eagerly coveted, and too valuable for constructing the smaller articles required by them, to leave any sufficient proportion for such purposes as building; while, of the architectural uses of stone and lime, they seem to be altogether ignorant.

But for all these wants, they are furnished, by the protecting providence of God, with an ample and highly appropriate substitute, however strange it may appear to the inhabitants of temperate regions. The snow which covers the soil for by far the greater portion of the year, offers them the refuge which their necessities require. Migrating, as they do, from time to time, in search of food, at the close of each day's journey, they erect their temporary dwellings, at little expense either of materials or workmanship; and, when they reach the station which they propose to occupy for a few months, even then their mode of building is of the simplest sort. It is thus described by Sir John Ross:"Having ascertained, by the rod used in examining seal-holes, whether the snow is sufficiently deep and solid, they level the intended spot by a wooden shovel, leaving beneath a solid mass of snow, not less than three feet thick.. Commencing, then, in the centre of the intended circle, which is ten feet or more in diameter, different wedgeshaped blocks are cut out, about two feet long, and a foot thick, at the outer part; then trimming them accurately by the knife, they proceed upward, until the courses, gradually inclining inwards, terminate in a perfect dome. The door, being cut out from the inside, before it is quite closed, serves to supply the upper materials. In the mean time, the women are employed in stuffing the joints with snow, and the boys in constructing kennels for the dogs." In the interior, the only furniture that is to be seen, consists of a sofa of snow, occupying nearly a third of the breadth of the area, about two feet and a half high, level at the top, and covered with various skins, forming the general bed or sleepingplace. The hut is lighted by a window of ice nicely

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inserted in the building, and secured by frozen snow; and the entrance is by a passage, long, narrow, and crooked, the outer aperture of which is planned, and from time to time altered, so as to secure the inmates from the prevailing winds of the season. The stores are laid up in smaller huts constructed to receive them; and they, and the kennels for the dogs, which invariably accompany the tribes, are formed of the same material.

It will naturally be conjectured, that such dwellings as have now been described, must be extremely cold, and liable, on any accession of artificial heat, to be rendered altogether uninhabitable, by the perpetual distillation of water from the icy walls. But there are several considerations which must be taken into the account, to enable us to judge of the suitableness of these habitations for the hardy race who occupy them. It must be noticed, in the first place, as a most important provision for their comfort, that snow is a very imperfect conductor of heat. The severe cold of the external air, therefore, makes but a small impression on the temperature of a chamber situated beneath a snow wall of considerable thickness. Then, from its extreme whiteness, it is, comparatively speaking, little liable to be dissolved by the heat of a lamp or fire, being much more ready to reflect caloric than to absorb it. These facts, however, striking as they are, it is clear, could not prevent the most annoying effects, were a strong heat constantly kept up within their circumscribed apartments. But here we find another important provision. The bodily frame, in all latitudes, speedily becomes inured, by habit, to the climate to which it is exposed, and the standard of temperature requisite for comfort accordingly rises or falls, as we live nearer the equator or the poles. While the African shivers under the summer warmth of the temperate zone, a degree of heat scarcely sufficient to raise the mercury to the freezing point affords to the patient Esquimaux, in his snowy hut, quite enough of warmth to make him comfortable ; and, even if the temperature should, at times, be raised so high as to promote a rapid distillation from the walls, his ideas of luxury do not render this a very serious in

convenience.

When we remember that it is not luxury which these rude tribes value, but simply shelter, we shall be less surprised with their contentment, especially when we learn that their clothing affords them sufficient security against the wetting influence even of melted snow. They experience quite as much of comfort as they desire, in finding themselves, during sleep, snug in their bags of fur, though the spot on which they lie be neither very dry nor very soft; for this defence, provided for them by the care of their Divine Preserver, answers to them all the ends for which it is needed.

4. In a region such as this, of frost and snow, of storm and tempest, it will easily be believed that the inhabitants are very dependant on fire, as a means of sustaining life; and the question will at once suggest itself, Whence can they derive fuel? Coals are unknown to them; and wood, we have seen, is much too valuable to be used for such a purpose. But they are not left destitute. Their little chambers are illuminated, during the whole course of their lengthened winter, by the cheerful, warm, and useful blaze of the lamp, which is replenished by oil from the seals yearly destroyed, in immense multitudes, by the native hunters. We have seen how valuable to the natives of these arctic regions, is the oily nature of their diet. Here, however, we find that Providence had another end in view in affording to the inhabitants of these countries so large a supply of fat and oil as that which is obtained from several of the cetaceous tribes which frequent their stormy seas. Nor is this an end less essential to the preservation of human life. There, where no other fuel could be had, and where, without fire, the race of men must soon have become extinct, were fixed these living reservoirs of combustible fluid, which it only needed the exercise of reason, of perseverance, and of ingenuity, to bring within the power of the human family; by which a provision has been made for their wants, infinitely better suited to the circumstances of their lot, in their inhospitable deserts, than any other description of fuel that could be named. Coals would have required the assistance of large beasts of bur

den, and the convenience of roads to remove them from the pits to the places where they were to be consumed, and the very nature of the climate rendered both of these equally impossible to be obtained. Wood, even supposing it could have been had, would have been almost as inconvenient; but the seals are generally to be met with readily, and killed with ease, affording, for a moderate degree of labor and of ingenuity, not only an ample banquet, but a very considerable quantity of the best oil, to feed the flame on which their food, their drink, and their comfort mainly depend. How can we contemplate such facts as these, without admiring the goodness and the care of that God who has so liberally furnished the means of subsistence, even in this wild, desolate, and barren country! G. J. C. D.

ELEVENTH WEEK-THURSDAY.

I. FROST.-PROVISION FOR CAUSING ICE TO FLOAT ON THE SURFACE.

WITHOUT heat, every thing would be solid; the true way, therefore, of viewing liquids, is to consider them as solids in a melted state. Bodies melt at different temperatures, according to their capacity of receiving heat, and to the nature of the action which this subtile principle produces on their particles. Thus, it requires one degree of intensity to melt stone, another to melt iron, another to melt lead, and another still to melt ice. In this view, ice may be considered as the natural state of the element, and water to be nothing else than ice rendered liquid, like other substances, by heat. When the short continuance of the sun above the horizon in winter, and his oblique rays, have greatly diminished the force of his influence, he is no longer able to preserve water in a liquid state, and then the process of crystallization

But there is a remarka

takes place, and ice is formed. ble difference between ice and other solid bodies, in the laws regulating its passage from a liquid to a crystallized state, which manifests beneficent intention.

Take water in its common state, and observe what occurs in reference to heat. It is the property of water, in common with other liquids, to communicate heat not so much by conduction, as it is called,—that is, by transmitting the temperature from particle to particle,-as by a motion among the particles themselves. Liquids, like solids, expand by heat and contract by cold. When heat, therefore, is applied to the bottom of a vessel, the expansion diminishes the specific gravity of the particles affected by it, and they rise to the surface, giving place to the colder and heavier particles, which again are heated in their turn, and ascend; and thus the process proceeds, till the whole liquid is of equal temperature. In cooling, the opposite process takes place; the particles, as they become colder at the surface, subside, while others, of higher temperature, supply their place, and this interchange and mixture goes on, till the whole body of the liquid becomes as cold as the surface. This remarkable property we have already noticed in speaking of the effect of the waters of the ocean in mitigating the temperature of different climates. Let us now see what would be the consequence if the same laws were to hold without limitation or exception. The cooled particles constantly descending, in virtue of their relative specific gravity, would, when the freezing point was reached, suddenly convert lakes and rivers, and the bed of the ocean itself, into a solid mass of ice, the congelation beginning at the bottom, and quickly spreading upward. Nor, when our deep waters were once frozen, would there be any natural means in existence by which they could be thawed to the bottom, because the heated particles, being the lightest, would constantly float at the top, and the warmth could only be diffused, as it is in solids, by the slower and less equable means of conduction. The experiment has been made, and water has been caused to boil by the

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