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my season; but these are, as we have feen, the means of floating and of navigating. Nature employs others, with which we are not acquainted, for preserving the fubftances of fruits, from the impreffions of the air. For example, the preserves, through the whole winter, many fpecies of apples and pears, which have no other covering than a pellicle so very thin, that it is impoffible to determine how fine it is.

Nature has placed other vegetables in humid and dry fituations, the qualities of which are inexplicable on the principles of our phyfics, but which admirably harmopize with the neceffities of the men who inhabit those places. Along the water-fide grow the plants and the trees which are the dryest, the lighteft, and, consequently, the best adapted for the purpose of croffing the stream. Such are reeds, which are hollow, and rushes which are filled with an inflammable marrow. It requires but a very moderate bundle of rushes to bear the weight of a very heavy man upon the water. On the banks of the lakes of the north are produced those enormous birchtrees, the bark of a fingle one of which is sufficient to form a large canoe. This bark is fimilar to leather in pliancy, and so incorruptible by humidity, that, in Ruffia, I have seen fome of it extracted from under the earth which covered powder magazines, perfectly found, though it had lain there from the time of Peter the Great.

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THE Kainsi has received from the Dutch its name of rock-jumper (klip-fpringer), merely on account of the nimbleness with which it bounds from rock to rock; and in fact, of all the gazelle tribe it is the most active. It is the fize of a roebuck of a year old, and has a coat of a yellowish grey; but its hair is fingular in this respect, that instead of being round, fupple, and solid, like that of moft quadrupeds, it is flat, harsh, and fo little adherent to the skin, that the leaft friction causes it to fall off. Hence nothing is more easy than to ftrip the animal of hair, dead or alive; friction, or even touching the skin, is fufficient for the purpose. Often have I endeavoured to preserve the fur of those which I had killed, without being able to effect it: notwithstanding all my precautions in skinning them, the greatest part of the hair fell off. Another particularity is the brittleness of the hair; which is such that, if a portion be taken between the fingers, and twisted with the other hand, the hairs break. This property, however, is common to several quadrupedswhich live among rocks.

This gazelle also differs from the other ipecies in the form of its hoof, which is not pointed like theirs, but rounded at the extremity; and as it is its cuftom, in leaping or walking, to pinch with the point of the hoof without bearing on the heel, it leaves a print diftinguishable from those of all the African antelopes. Its flesh is exquifite, and much in request, efpécially among the hunters. The panthers and leopards are equally fond of it. I have heard the Hottentots relate that these animals unite to hunt the kainfi; and that when

when the latter has taken refuge on the point of fome steep rock, one of them will go below to wait for the prey, while the rest advance and try to force it to precipitate itself.

I do not, however, give credit to these pretended affociations of animals of the tyger kind.

The chace of the kainfi is very amufing. It can scarcely, indeed, be forced by dogs, from whom it foon escapes by its inconceivable agility, and gets out of their reach on the point of fome infulated rock; on which it remains for hours together, safe from all purfuit, and fufpended, as it were, over the abyss:-but in this po. fition it seems to offer the best mark to the ball or the arrow; and if the hunter cannot always easily get at it after he has killed it, he may almost constantly shoot it. Many times have I been witness of the extreme nimblenefs of the animal: but one day I saw an instance of it which astonished me. I was hunting one, and from the nature of the place it was suddenly so preffed by my dogs, that it seemed to have no poffibility of escape. Before it, was an immense perpendicular crag, which stopped it short: but on this wall, which I thought vertical, was a little ledge projecting two inches at most, which the kainsi had perceived. He leaped on it, and to my great surprise held faft.

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thought at least he would foon be precipitated; and my dogs themselves so much expected it, that they ran below to seize him when he should fall. I threw stones at him to endeavour to make him lose his balance. All at once, as if he had divined my intention, he col

lected all his force, sprang to my fide, flew over my head, and then, alighting fome paces from me, escaped like lightning. I might still eafily have thot him, but his leap had fo furprized and pleased me that I gave him his life. My dogs only were taken in, who, confused at his efcape, did not return to me without a kind of shame.

Reflections of certain effects of Heat and Cold on the living System. By I komas Beddoes, M., D. Fram Medical Facts and Obfervations.

I know not whether it has been observed that the inflammations particularly those of the eyes, which are so frequent in hot climates where it is the custom to fleep during the summer in the open air, are to be referred to the fucceffion of heat to cold. Travellers, especially those into Egypt, have variously attempted to account for this phænome non. Hafielquist imputes it to certain miafmata arifing from the almost empty refervoirs in which the water of the Nile is preserved from inundation to inundation. This is, however, a mere hypothefis, unconfirmed by any strict analogy: nor is the supposed cause in any way brought home to the effect. As little, in my opinion, can the inflammation of the eyes be ascribed to the influence of the nocturnal light of the heavens upon the eye, the eyelids, being more or less closed during fleep. The cause seems inadequate. It is common in this coun try to fleep in chambers not less strongly illuminated (if not more so) than in Egypt, during the night, without any inconvenience to our fight. fight. Besides, I think, if we could suppose the eye to be so dazzled by the light of the night as to be injured, the injury ought to fall upon the nerve, and not upon the eyelids and external parts. The nitrous particles with which Alpinus imagines the atmosphere of Egypt to the impregnated, will not, I suppose, be confidered as a cause more probable than any of the preceding: but the following paffage may serve to give an idea of the nature of the complaint in question, and its frequency, at Cairo. "Plurimasque (oculorum lippitudines) Cayri eafdemque per omnia anni tempora homines invadere ob nitrofum pulverem, qui continuè oculos habitantium mordicat, & calefacit, obfervatur, longè maximéque in æstatis primâ parte, quo tempore calor ambientis fummè calidi oculos inflammat, taliumque numerum auget. Sparfim vero per urbem toto anno hæ oculorum inflammationes vagantur; atque epidemicæ plurimæ in primâ æstatis parte calidiffimâ inæqualiffimâque ob vehementiffimum meridionalium ventorum calorem, atque inflammatarum arenaruns copiam, quæ ab iifdem ventis asportantur. Eo enim anni tempore è centum hominibus quinquaginta faltem lippientes observantur." (De Medicin. Ægypt. p. 24.) The flying sand must be troublesome, and probably, in many cafes, fupports and increases the inflammation, and in some may give rise to it; but the following fact, which seems to me to render the induction complete, shows that the true and general cause is the great inequality between the tem

perature of the night and day; to which cause signal effect is given by the practice of fleeping sub dio. Mr. Clarkson (in his essay on the impolicy of the African flavetrade) informs us (p. 71) that, "when the flaves are brought on board, the seamen, to make room for them, are turned out of their apartments between decks, and sleep, for the most part, either on deck or in the tops of the vessel during the whole of the middle passage; or from the time of their leaving the coast of Africa (where the days are excessively hot, and the dews are excessively cold and heavy, ibid. p. 68), to that of their arrival at the West-India islands." "From this bad lodging," he proceeds, "and this continual expofure to colds and damps, and suddenly afterwards to a burning fun, fevers originate which carry many of them off. Nor is this the only effect which this continual viciffitude from heat to extreme dampness and cold has upon the furviving crew: inflammatory fevers neceffarily attack them. This fever attacks the whole frame; the eye feels the inflammation most. Thisinflammation terminates either in difperfion or fuppuration : in the first instance the eyes are saved; in the latter they are loft.

The inflammation of the eye is not the only disease produced in Egypt by the succession of hot days to cool nights any more than on board our flave-ships; in both fituations caufes and effects run parallel, as the reader will find upon recurring to Alpinus and the later travellers. The well-known danger of exposure to dews in hot climates, climates, and indeed in all climates, in certain cafes, seems to depend upon the fame principle. It is also probable that the heat of the preceding day enables the dews of the night to prepare the system for the ftimulating effects of the heat of the fucceeding day; fo that, of two perfons who should expose themselves without precaution to the cold of night and the heat of the following day, he who should have been moft exhaufted the day before by the heat, would, if other circumftances could be rendered alike equal, be most injured by the next alternation.

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* See Niebuhr's Thermometrical tables in the first volume of his Travels.

Several circumstances, such as the redness and swelling of the parts expofed to cold together with the frequent occurrence of inflammatory diforders not long after expofure to cold, were calculated to miflead observers into a belief that these diforders were the direct effect of cold. Yet the great difference in the state of a part during inflammation, and under the influence of cold, might have induced them to suspect that so flight an analogy might be illufive: and, after taking into the account other well-afcertained facts they ought to have concluded that the theory was false. Linnæus, in a paper in the Amœnitates Academicæ, expresses his aftonishment at the impunity with which the heated Laplander rubs himself with snow, or even rolls in the snow, and drinks the cold snow-water. We every day fee horses in a state of the most profuse perspiration freely washed with cold water, and always without injury. I have feveral times within these two years caufed horfes accustomed to be flabled, to be turned outfor a singlenight VOL. XXXVIII.

in winter: and nocough, catarrh, or other diforder, has ever been the confequence. It appears, therefore, to me, that, within certain limits, and those not very narrow. the tranfition from a higher to a lower temperature is attended with no danger to animals in a state of tolerable health; and a perfon, I conceive, might fuddenly pass from a higher to a lower temperature without inconvenience, even where the difference is fo great as to be capable of producing confiderable inflammation, if the change should be made with equal celerity in a contrary direction. On this, though an interesting subject for obfervations on man, and experiments on animals, we want precise facts; and I ftate the principle in order to induce obfervers to compare it with the facts that fall in their way. Befides the fucceffion of heat and vice versa, there is a third cafe well worthy of confideration; and this wherepart of the body is exposed to one of these powers, and the remaining part to the other; as, for instance, where a ftream of comparatively cold air flows upon part of the body of a perfon fitting in a warm room, and perhaps alfo drinking stimulating liquors. making chemical experiments it often happens that a cold (catarrh) is taken, if the hands be much inimersed in cold water, when the laboratory is much heated; by adding warm water, to raife the temperature of that in the trough, this danger is easily avoided. In these cases the effect seems to be the fame as that of the fucceffion of heat to cold. In perfons whofe bowels are extremely liable to be affected, it sometimes happens, as I have myself known it to happen, that

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that the removal of a foot into a cold part of the bed, after the body has become warm in bed, shall bring on acute pain in the bowels; and yet no pain is produced in getting into bed, though the temperature be the fame, and perhaps lower, than that of the part into which the foot is removed; and, probably, total immerfion into cold water would not produce any pain in the bowels. The laws of fuch phænomena, however deserving of investigation, have, as yet, scarcely been an object of attention with pathologifts. It is probable that the phænomena, in any given cafe, are regulated by two circumstances: first, by the excess of heat (or the strength of the stimulus, whatever it be,) to which the greater part of the body is exposed, above that to which the smaller is expofed. The second circumstance is the difference between the extent of the heated and cooled surfaces. When the latter is not extremely minute, and yet confined within moderate limits, the inflammatory effects seem to be confiderable. Should the circumstances be reversed, and a stream of air, so warm as to convey heat to the body, inftead of carrying it away, play upon a small part of its furface, the rest being exposed to a moderate or a low temperature, it is probable the result would be the same as when moderate cold fuc'ceeds to warmth, i. e. no bad effect would follow.

Account of the Manner of treating Bees in Portugal. From Murphy's Travels in that Country.

TO form a colony of bees, a spot of ground is chofen for the hives,

exposed towards the south or foutle east, well sheltered from the northern, blasts, and furrounded with fhrubs and flowers; of the latter, the best is rosemary. The richer the neighbouring grounds are the better, for bees are faid to range for food to the diftance of a league from their homes. The fituation being chofen, lanes must be cut through the shrubby thickets of five or fix feet wide. The fences between the lanes should be about the fame dimenfions, and formed at intervals into small recesses, like bowers or niches, to receive the hives.

The figures of the hives ufed here in general are cylindrical; in height about twenty-seven inches by fourteen diameter. They are formed of the rind of the corktree, and covered with a pan of earthen-ware inverted, the edge of which projects over the hive like a cornice. The whole is faftened with pegs made of fome hard and durable wood, and the joints stopped with peat. In the front of the cylinder, at the height of about eight inches, there is a finall aperture where the bees enter. The infide is divided into three equal divifions, which are separated by cross sticks: here the bees form their cotabs or cells.

When the bees swarm, which is usually in the month of May or June, the hives are placed to receive them where they light. If they defcend on a tree, they are fhaken off: the person who perfornis this operation muft not be afraid of them, as they do not commonly fting unless they are irritated; it will be safer, however, to cover the head with a wire-mask, and the hands with gloves.

Some bees are so wild, that they fly

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