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

Nature has placed other vege. tables in humid and dry fituations, the qualities of which are inexplicable on the principles of our phyfics, but which admirably harmonize with the neceffities of the men - who inhabit thofe places. Along the water-fide grow the plants and the trees which are the dryeft, the lighteft, and, confequently, the beft adapted for the purpose of croffing the ftream. Such are reeds, which are hollow, and rufhes which are filled with an inflammable marrow. It requires but a very moderate bundle of rufhes to bear the weight of a very heavy man upon the water. On the banks of the lakes of the north are produced thofe enormous birchtrees, the bark of a fingle one of which is fufficient to form a large canoe. This bark is fimilar to leather in pliancy, and fo incorruptible by humidity, that, in Ruffia, I have feen 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.

Account of the Kainfi, a Species of Gazelle or Antelope. From le Vaillani's Second Journey into the Interior of Africa,

THE Kainfi has received from the Dutch its name of rock-jumper (klip-fpringer), merely on account of the nimblenefs 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 refpect, that inftead of being round, fupple, and folid, like that of moft quadrupeds, it is flat, harth, and fo little adherent to the fkin, that the leaft friction caufes it to fall off. Hence nothing is more eafy than to ftrip the animal of hair, dead or alive; friction, or even touching the fkin, is fufficient for the purpofe. 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 fkinning them, the greatest part of the hair fell off. Another particularity is the brittleness of the hair; which is fuch that, if a portion be taken between the fingers, and twisted with the other hand, the hairs break. This property, however, is common to feveral quadrupedswhich live among rocks.

This gazelle alfo differs from the other 1pecies 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 thofe of all theAfrican antelopes. Its flesh is exquifite, and minch in requeft, efpecially among the hunters. The panthers and leopards are equally fond of it. I have heard the Hottentots relate that thefe animals unite to hunt the kainfi; and that

when

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

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

lected all his force, fprang to my fide, flew over my head, and then, alighting fome paces from me, efcaped like lightning. I might ftill 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, confuled at his efcape, did not return to me without a kind of flame.

The chace of the kainfi is very amufing. It can fcarcely, indeed, be forced by dogs, from whom it foon efcapes by its inconceivable agility, and gets out of their reach on the point of fome infulated rock; on which it remains for hours together, fafe from all purfuit, and fufpended, as it were, over the abyss-but in this po. fition it feems to offer the beft mark to the ball or the arrow; and if the hunter cannot always eafily get at it after he has killed it, he may almost conftantly thoot it. Many times have I been witnefs of the extreme nimblenefs of the animal: but one day I faw an inftance of it which aftonifhed me. I was hunting one, and from the nature of the place it was fuddenly fo preffed by my dogs, that it feemed to have no poflibility of efcape. Before it, was an immenfe perpendicular crag, which flopped it fhort but on this wall, which I thought vertical, was a little ledge projecting two inches at moit, which the kainfi had perceived. He leaped on it, and to my great furprise held faft. I thought at least he would foon be precipitated; and my dogs themfelves fo much expected it, that they ran below to feize him when he thould fall. I threw ftones at him to endeavour to make him lofe his balance. All at once, as if he had divined my intention, he col

Reflections of certain effects of Heat and Cold on the living Syftem. By Thomas Beddoes, M. D. From Medical Fats and Obfervations.

I know not whether it has been obferved that the inflammations particularly those of the eyes, which are fo frequent in hot climates where it is the custom to fleep during the fummer in the open air, are to be referred to the fucceffion of heat to cold. Travellers, especially thofe into Egypt, have varioufly attempted to account for this phænomenon. Haffelquift imputes it to certain miafmata arifing from the almoft empty refervoirs in which the water of the Nile is preferved from inundation to inundation. This is, however, a mere hypothefis, unconfirmed by any ftri&t analogy: nor is the fuppofed caufe 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 caufe feems inadequate. It is common in this coun try to fleep in chambers not lefs ftrongly illuminated (if not more fo) than in Egypt, during the night, without any inconvenience to our

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fight. Befides, I think, if we could fuppofe the eye to be fo 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 fuppofe, be confidered as a caufe more probable than any of the preceding but the following paffage may ferve to give an idea of the nature of the complaint in queftion, and its frequency, at Cairo. "" Plurimafque (oculorum lippitudines) Cayri eafdemque per omnia anni tempora homines in vadere ob nitrofum pulverem, qui continuè oculos habitantium mordicat,, & calefacit, obfervatur, longè maximéque in æftatis primâ parte, quo tempore calor ambientis fummè calidi oculos inflammat, taliumque morborum numerum auget. Sparfim vero per urbem toto anno hæ oculorum inflammationes yagantur; atque epidemicæ plurima in primâ æftatis parte calidiffimâ inæqualiflimâque ob vehementiffimum * meridionalium ventorum calorem, atque inflammatarum arenarum copiam, quæ ab iifdem ventis afportantur. Eo enim anni tempore è centum hominibus quinquaginta faltem lippientes obfervantur." (De Medicin. Egypt. p. 24.) The flying fand muft be troublesome, and probably, in many cafes, fupports and increases the inflammation, and in fome may give rife to it; but the following fact, which feems to me to render the induction complete, fhows that the true and general caufe is the great inequality between the tem

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perature of the night and day; to which caufe fignal effect is given by the practice of fleeping fub dio. Mr. Clarkson (in his effay on the impolicy of the African flavetrade) informs us (p. 71) that, "when the flaves are brought on board, the feamen, to make room for them, are turned out of their apartments between decks, and fleep, for the most part, either on deck or in the tops of the vessel during the whole of the middle paffage; or from the time of their leaving the coaft of Africa (where the days are exceffively hot, and the dews are exceffively cold and heavy, ibid. p. 68), to that of their arrival at the Weft-India islands." "From this bad lodging," he proceeds,

"and this continual expofure to colds and damps, and fuddenly 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 dampnefs and cold has upon the furviving crew: inflammatory fevers neceffarily attack them. This fever attacks the whole frame; the eye feels the inflammation most. This inflammation terminates either in difperfion or fuppuration: in the firft inftance the eyes are faved; in the latter they are loft.

The inflammation of the eye is not the only disease produced in Egypt by the fucceffion of hot days to cool nights any more than on board our flave-fhips; in both fi tuations caufes and effects run parallel, as the reader will find upon recurring to Alpinus and the later travellers. The well-known danger of expofure to dews in hot climates,

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

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climates, and indeed in all climates, in certain cafes, feems 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 fyftem for the ftimulating effects of the heat of the fucceeding day; fo that, of two perfons who fhould expofe themselves without precaution to the cold of night and the heat of the following day, he who fhould 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.

Several circumftances, fuch as the redness and fwelling of the parts expofed to cold together with the frequent occurrence of inflammatory diforders not long after expofure to cold, were calculated to mislead obfervers into a belief that thefe diforders were the direct effect of cold. Yet the great difference in the ftate of a part during inflammation, and under the influence of cold, might have induced them to fufpect 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 falfe. Linnæus, in a paper in the Amoenitates Academicæ, expreffes his astonishment at the impunity with which the heated Laplander rubs himself with fnow, or even rolls in the fnow, and drinks the cold fnow-water. We every day fee horses in a state of the most profufe perspiration freely washed with cold water, and always without injury. I have feveral times within these two years caufed horfes accustomed to be fiabled,to be turned out for a fingle night VOL. XXXVIII.

in winter: and no cough, catarrh, or other diforder, has ever been the confequence. It appears, therefore, to me, that, within certain limits, and thofe not very narrow, the tranfition from a higher to a lower temperature is attended with no danger to animals in a ftate 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 fhould be made with equal celerity in a contrary direction. On this, though an interefting fubje&t for obfervations on man, and experiments on animals, we want precife facts; and I ftate the principle in order to induce obfervers to compare it with the facts that fall in their way.

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Befides the fucceffion of heat and vice verfa, there is a third cafe well worthy of confideration; and this wherepart of the body is expofed to one of thefe powers, and the remaining part to the other; as, for inftance, where a fiream of comparatively cold air flows upon part of the body of a perfon fitting in a warm room, and perhaps alfo drinking ftimulating liquors. making chemical experiments it often happens that a cold (catarrh) is taken, if the hands be much inimerfed 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 eafily avoided. In thefe cafes the effect seems to be the fame as that of the fucceffion of heat to cold. In perfons whose bowels are extremely liable to be affected, it fometimes happens, as I have myfelf known it to happen,

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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, fhall 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 immersion into cold water would not produce any pain in the bowels. The laws of fuch phæ nomena, however deferving of investigation, have, as yet, fcarcely been an object of attention with pathologifts. It is probable that the phænomena, in any given cafe, are regulated by two circumftances: firft, by the excess of heat (or the ftrength of the ftimulus, whatever it be,) to which the greater part of the body is expofed, above that to which the smaller is expofed. The fecond circumftance is the difference between the extent of the heated and cooled furfaces. When the latter is not extremely minute, and yet confined within moderate limits, the inflammatory effects feem to be confiderable. Should the circumftances be reverfed, and a ftream of air, fo warm as to convey heat to the body, inftead of carrying it away, play upon a fmall part of its furface, the reft being expofed to a moderate or a low temperature, it is probable the refult would be the fame as when moderate cold fucceeds 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 fpot of ground is chofen for the hives,

expofed towards the fouth or foutheaft, well fheltered from the nor thern, blafts, and furrounded with fhrubs and flowers; of the latter, the beft is rosemary. The richer the neighbouring grounds are the better, for bees are faid to range for food to the distance of a league from their homes. The fituation being chofen, lanes must be cut through the fhrubby thickets of five or fix feet wide. The fences between the lanes fhould be about the fame dimenfions, and formed at intervals into fmall receffes, like bowers or niches, to receive the hives.

The figures of the hives ufed here in general are cylindrical; in height about twenty-feven 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 final aperture where the bees enter. The infide is divided into three equal divifions, which are feparated by crofs flicks here the bees form their combs or cells.

When the bees fwarm, which is ufually 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 perfon who performs this operation must not be afraid of them, as they do not commonly fting unless they are irritated; it will be fafer, however, to cover the head with a wire-mark, and the hands with gloves.

Some bees are fo wild, that they

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