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when its shoots are cut, and the young scions only permitted to remain, the plant becomes less, and less able to resist the encroachments of the surrounding underwood, by which means it not unfrequently becomes choaked and overgrown.

Another, and not an unimportant concern, demands the attention of government-the collection and preparation of the receptacle of the embryo seed of the cinnamon plant, the casia bud of commerce. The full grown trees of the interior will afford them in great abundance. They are frequently substituted for the more expensive cinnamon, and fetch a good price. The collection of them in Ceylon might be extensive, and effected at a very small expense. Labour, which is all that is required, is cheap. They could be collected by boys and the drying, sorting, &c. of them might be entrusted to females. We might soon be able to rival the Chinese monopoly of this article. The Dutch, however eager they were to extend the exportation of colonial produce, seem to have entirely neglected the preparation of this important article of trade Indeed I have not been able to learn that they were aware of the fact that casia buds are the produce of the cinnamon plant. The native headmen now employed in the cinnamon department, and who were in the same situation under the Dutch, express their entire igno

rance of the circumstance.

In the London New Price Current of Jan. 10, 1815, casia buds are quoted at from 321. to 371. per cwt. or from about 5s. 6d, to 6s. 6d. per lb. The profit upon this arVOL. LIX.

ticle might be considerable. The more carefully and extensively we consider the subject, we shall, I think, be the more convinced that we must trust chiefly to the plantations for cinnamon of the finest quality, and that notwithstanding the recent important acquisition of the interior of the island, we should prosecute the cultivation of cinnamon with unabated zeal and perseverance.

ON THE GREENLAND OR POLAR ICE.

By W. Scoresby, jun. M.W.S. [From Memoirs of the Wernerian Natural History Society.]

Greenland is a country where every object is strikingly singular, or highly magnificent. The atmosphere, the land, and the ocean, each exhibit remarkable or sublime appearances.

With regard to the atmosphere, several peculiarities may be noticed, viz. its darkness of colour and density; its frequent production of crystallised snow in a wonderful perfection and variety of form and texture; and its astonishing sudden changes from calm to storm,-from fair weather to foul, and vice versa.

The land is of itself a sublime object; its stupendous mountains rising by steep acclivities from the very margin of the ocean to an immense height, terminating in ridged, conical, or pyramidal summits; its surface, contrasting its native protruding dark-coloured rocks, with its burthen of purest snow; the whole viewed under the density of a gloomy sky, forms a picture impressive and grand. Its most remarkable inhabitant is the White or Polar Bear, which 2 M indeed

indeed also occurs on the ice. This ferocious animal seems to be the natural lord of those regions. He preys indiscriminately on quadruped, fowl, reptile, and fish; all behold him with dread, and flee his presence. The seals signify their fear of him by their constant watching, and betake themselves precipitately to the water on his approach. Carrion, therefore, (of which the carcase of the whale is at a certain season the most plentiful), affords him a passive, sure, and favourite food. His sense of smelling is peculiarly acute in his march, he is frequently observed to face the breeze, to rear his head, and snuff the passing scent, whereby he can discover the nearest route to his odorous banquet, though the distance be incredibly great.

The water of the ocean is not the least interesting of the elements, particularly as affording the bed, and partly the materials for the most prodigious masses of ice. Its colour is peculiar. Its products are numerous, and of particular importance. It is here that the huge Mysticetus, or Whalebone Whale, takes up his residence, and collects his food ;

it is here that he sports and astonishes, by his vast bulk and proportionate strength; and it is here that he becomes the object of maritime adventure, and a source of commercial riches.

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stupendous masses, known by the name of Ice-Islands, FloatingMountains, or Icebergs, common to Davis' Straits and sometimes met with here, from their height, various forms, and the depth of water in which they ground, are calculated to strike the beholder with wonder: yet the fields of ice, more peculiar to Greenland, are not less astonishing. Their deficiency in elevation is sufficiently compensated by their amazing extent of surface. Some of them have been observed near a hundred miles in length, and more than half that breadth; each consisting of a single sheet of ice, having its surface raised in general four or six feet above the level of the water, and its base depressed to the depth of near twenty feet beneath.

The various kinds of Ice described.

The ice in general is designated by a variety of appellations, distinguishing it according to the size or number of pieces, their form of aggregation, thickness, transparency, &c. I perhaps cannot better explain the terms in common acceptation amongst the whale-fishers, than by marking the disruption of a field. The thickest and strongest field cannot resist the power of a heavy swell; indeed, such are much less capable of bending without being dissevered, than the thinner ice which is more pliable. When a field, by the set of the current, drives to the southward, and being deserted by the loose ice, becomes exposed to the effects of ground swell, it presently breaks into a great many pieces, few of which will exceed

forty

forty or fifty yards in diameter. Now, such a number of these pieces collected together in close contact, so that they cannot, from the top of the ship's mast, be seen ́over, are termed a pack.

When the collection of pieces can be seen across, if it assume a circular or polygonal form, the name of patch is applied; and it is called a stream when its shape is more of an oblong, how narrow soever it may be, provided the continuity of the pieces is preserved.

:

Pieces of very large dimensions, but smaller than fields, are called floes thus, a field may be compared to a pack, and a floe to a patch, as regards their size and external form.

Small pieces which break off, and are separated from the larger masses by the effect of attrition, are called brash-ice, and may be collected into streams or patches.

Ice is said to be loose or open, when the pieces are so far separated as to allow a ship to sail freely amongst them; this has likewise been called drift-ice.

A hummock is a protuberance raised upon any plane of ice above the common level. It is frequently produced by pressure, where one piece is squeezed upon another, often set upon its edge, and in that position cemented by the frost. Hummocks are likewise formed, by pieces of ice mutually crushing each other, the wreck being coacervated upon one or both of them. To hummocks, the ice is indebted for its variety of fanciful shapes, and its picturesque appearance. They occur in great numbers in heavy packs, on the edges and occasionally in

the middle of fields and floes. They often attain the height of thirty feet or upwards.

A calf, is a portion of ice which has been depressed by the same means as a hummock is elevated. It is kept down by some larger mass s; from beneath which, it shews itself on one side. I have seen a calf so deep and broad, that the ship sailed over it without touching, when it might be observed on both sides of the vessel at the same time; this, however, is attended with considerable danger, and necessity alone warrants the experiment, as calves have not unfrequently (by a ship's touching them, or disturbing the sea near them) been called from their sub-marine situation to the surface, and with such an accelerated velocity, as to stave the planks and timbers of the ship, and in some instances, to reduce the vessel to a wreck.

Any part of the upper superficies of a piece of ice, which comes to be immersed beneath the surface of the water, obtains the name of a tongue.

A bight signifies a bay or sinuosity, on the border of any large mass or body of ice. It is supposed to be called bight from the low word bite, to take in, or entrap; because, in this situation, ships are sometimes so caught by a change of wind, that the ice cannot be cleared on either tack; and in some cases, a total loss has been the consequence.

Comparison of Ice frozen from Sea

Water and Rain-Water.

When the sea freezes, the greatest part of the salt it contains is deposited, and the frozen spongy 2 M 2

mass

mass probably contains no salt, but what is natural to the seawater filling its pores. Hence, the generality of ice affords freshwater, when dissolved. As, however, the ice frozen from seawater does not appear so solid and transparent as that procured from snow or rain-water, sailors distinguish it into two kinds, accordingly as it seems to have been formed from one or the other.

Ice frozen from Sea-Water.

What is considered as saltwater ice, is porous, white, and in a great measure opaque, (except when in very thin pieces), yet transmits the rays of light with a greenish shade. It is softer, and swims lighter than fresh-water ice, and when dissolved, produces water sometimes perfectly fresh, and sometimes saltish; this depends in a great measure on the situation from whence it is taken: such parts as are raised above the surface of the sea in the form of hummocks, appear to gain solidity by exposure to the sun and air, and are commonly fresh, whilst those pieces taken out of the sea are somewhat salt. Although it is very probable, that this retention of salt may arise from the sea-water contained in its pores, yet I have never been able to obtain, from the water of the ocean, by experiment, an ice either compact, transparent, or fresh. That the sea-water has a tendency to produce fresh ice, however, is proved from the concentration observed in a quantity exposed in an open vessel to a low temperature, by the separation of the salt from the crystals of ice,

in the progress of the freezing. Thus it is, that in the coldest weather, when a ship exposed to a tempestuous sea is washed with repeated sprays, and thereby covered with ice, that in different places obstructing the efflux of the water overboard, a portion always remains unfrozen, and which, on being tasted, is found to contain salt highly concentrated. This arises from the freezing point of water falling in a certain ratio according to the degree of saltness; thus, though pure water, of specific gravity 1.0000, freeze with a temperature of 32°, water of specific gravity 1.0263, containing about 54 oz. (avoird.) of salt in every gallon of 231 cubic inches, that is, with the degree of saltness common to the Greenland seas, freezes at 28. Sea-water concentrated by freezing, until it obtains the specifie gravity of 1.1045, requires a temperature of 133° for its congelation, having its freezing point reduced 1810 below that of pure water; and water saturated with sea-salt remains liquid, at a temperature of -4°.

Thus, we are presented with a natural process for extracting salt from the sea, at least for greatly facilitating that process in a concentration of the saline particles, by the agency of frost.

When salt-water ice floats in the sea at a freezing temperature, the proportion above, to that below the surface, is as 1 to 4 nearly; and in fresh water, at the freezing point, as 10 to 69, or 1 to nearly. Hence, its specific gravity appears to be about 0.873. Of this description is all young ice as it called, which forms a considerable

considerable proportion of packed and drift ice in general; where it occurs in flat pieces commonly covered with snow, of various dimensions, but seldom exceeding fifty yards in diameter.

Fresh-Water Ice.

Fresh-water ice, is distinguished by its black appearance when floating in the sea, and its beautiful green hue and transparency when removed into the air. Large pieces may occasionally be obtained, possessing a degree of purity and transparency, equal to that of the finest glass, or most beautiful crystal; but generally, its transparency is interrupted by numerous small globular or pear-shaped air-bubbles: these frequently form continuous lines intersecting the ice in a direction apparently perpendicular to its plane of formation.

Fresh-water ice is fragile, but hard; the edges of a fractured part are frequently so keen, as to inflict a wound like glass. The homogeneous and most transparent pieces, are capable of concentrating the rays of the sun, so as to produce a considerable intensity of heat. With a lump of ice, of by no means regular convexity, I have frequently burnt wood, fired gunpowder, melted lead, and lit the sailors' pipes, to their great astonishment; all of whom, who could procure the needful articles, eagerly flocked around me, for the satisfaction of smoking a pipe ignited by such extraordinary means. Their astonishment was increased, on observing, that the ice remained firm and pellucid, whilst the solar rays emerging

therefrom were so hot, that the hand could not be kept longer in the focus, than for the space of a few seconds. In the formation of these lenses, I roughed them with a small axe, which cut the ice tolerably smooth; I then scraped them with a knife, and polished them merely by the warmth of the hand, supporting them during the operation in a woollen glove. 1 once procured a piece of the purest ice, so large, that a lens of sixteen inches diameter was obtained out of it; unfortunately, however, the sun became obscured before it was completed, and never made its appearance again for a fortnight, during which time, the air being mild, the lens was spoiled.

The most dense kind of ice, which is perfectly transparent, is about one-tenth specifically lighter than sea-water at a freezing temnperature. Plunged into pure water, of temperature 32o, the proportion floating above to that below the surface, is as 1 to 15, and placed in boiling fresh water, it barely floats. Its specific gravity is about 0.937.

Fields, bergs, and other large masses, chiefly consist of this kind of ice. Brash-ice likewise affords pieces of it, the surfaces of which are always found crowded with conchoidal excavations when taken out of the sea.

On the Formation of Ice on the Sea.

Some naturalists have been at considerable pains to endeavour to explain the phenomena of the progressive formation of the ice in high latitudes, and the derivation of the supply, which is annually furnished, for replacing the great quantities

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