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is weakened, this proportion requires great accuracy in the adjustment; while greater powers of life allow a greater latitude.

I was led to make these observations by attending to perfons who are frofi-bitten; the effect of cold in this cafe being that of leffening the living principle. The powers of action remain as perfect as ever, only weakened; and heat is the only thing wanting to put these powers into action; yet heat.uft at first be gradually applied, and proportioned to the quantity of the living principle; but as that increases you may increase the degree of heat.

If this method is not observed, and too great a degree of heat is at first applied, the perfon or part loses entirely the living principle, and mortification enfues. This process invariably takes place with regard to men. The fame thing, I am convinced, happens to other animals. If an eel, for inftance, is exposed to a degree of cold sufficiently intense to benumb it till the remains of life are scarcely perceptible, and still retained in cold of about 40 degrees; this small proportion of living principle will continue for a confiderable time without diminution or increase; but if the animal is afterwards

placed

placed in a heat of 60 degrees, after fhewing strong figns of returning life, it will die in a few minutes.

If a lizard, or fnake, be taken from its autumnal hiding place, and expofed to the fun's rays, or placed in any fituation which would give vigour to the fame kind, poffeffed of a larger thare of life, they will immediately fhew figns of increased * life, but quickly fink under the experiment and die; while others, reduced to the fame degree of weakness, as far as appearances can discover, will live for many weeks, if kept in a degree of cold proportioned to the quantity of life they poffefs.

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I obferved many years ago, in fome of the colder parts of this ifland, that when intenfe cold had forced blackbirds or thrushes to take fhelter in out-houses, any of them that had been caught, and from an ill-judged compaffion exposed to a confiderable degree of warmth, died very foon. The reafon of this I did not then underftand; but I am now fatisfied, that it was owing, as in other inftances, to the degree of heat being increased

Sedative powers, fays Dr. BROWN, weaken the tone of the fibre, but by accumulating IRRITABILITY, they predispose the fibre to an inordinate action upon the application of a flight ftimulus. How much does Dr. BROWN'S and JOHN HUNTER's doctrine then coincide, if we except the difference of expreffion!

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too fuddenly for the proportion of life remaining in the

animal.

From thefe facts it appears, that warmth calls forth a great exertion of the living powers; and that an animal in a weakly state may be obliged to exert a quantity of the actions of life fufficient to deftroy the very powers themselves. Heat must therefore be carefully regulated according to the return of the powers of life, and must be adjusted accordingly.-HUNTER.

[Heat is fo effential to life, that without a certain degree of it, neither animals nor vegetables could subsist, The eggs of oviparous animals, the feeds of vegetables, and growing plants, difcover, by the thermometer applied to their internal parts, a degree of temperature evidently exceeding that of the circumambient atmofphere. Heat accompanies the embryo from the earliest period to the last stage of its existence, and therefore has been confidered by fome as the fource of vitality. Hence, the fecundating egg brings forth in due feafon, whether the proper degree of heat be communicated by incuba tion, or by the temperature of a well-regulated oven. Hence, alfo, the myriads of animated beings, which,

from

from imperceptible ova, are ushered into existence by the fummer's fun! Hence dormant animals are roufed from a torpid ftate, by the vernal warmth; and hence too, drowned perfons have fometimes been reanimated by the folar rays

From thefe, and fimilar confiderations, it was very natural to conclude, that to restore heat to the body, must be one of the most powerful means of reftoring animation. Accordingly, it has hitherto been attempted, by the application of artificial heat; under an idea, that until this could be accomplished, every other means would prove ineffectual: without confidering, perhaps, that an inanimate substance of fuch a bulk as the human body, containing a large quantity of matter under a fmall furface muft acquire heat very flowly: that to accomplish this in the internal parts (were it even practicable with safety) would demand great length of time, during which other measures no lefs effential must be poftponed.

When refpiration ceafes in a drowned animal, the power of generating heat is fufpended, and the body lofes the remains of its natural warmth, till at length it is re duced to the temperature of the furrounding medium. During this, if we attempt to raise the heat fuddenly to

the

or flannels wrung out of the fame, or in vinegar, might

in fome measure fupply its place. These

may

be ap

plied to the region of the ftomach; to the arm-pits; to the groin; and to the extremities: their warmth being retained by a covering of warm flannel. The room should have no vifitants to corrupt the air, its heat fhould be between 56 to 64 degrees of Fahrenheit's fcale. But let it be ever remembered, that till the ge nerating power can be restored to the frame, it is in vain that we attempt by thefe, or any other means, to raise the heat of the body to the natural standard.-Dr. FoTHERGILL.]

PROP. VI.

Motion may poffibly be of service, it may at leaft be tried; but, as it has less effect than any other of the above prescribed stimuli, it should be the last part of the procefs.

I would recommend to the operator the fame care in regulating the proportion of every one of these methods, as I did before in the application of heat; as every one of them may poffibly have the fame property of entirely

destroying

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