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on the male : but the voracity of the young, as they increase in size becomes so pressing, that both the parents can with difficuity appcasc the incessantly craving appetites of their offspring, The supply of provisions is so copious, that a family of Hottentots ssured me of their having subsisted for two months by daily robbing a nest of this bird which was in their neighbourhood. I am inclined to think this account by no means improbable, after having been myself witness of the rapaciousness of a griffard which I kept alive for some time. His wing being broken, and he being unused to captivity, he refuæed for three days every thing that was offered: but as soon as he began to take food he became absolutely insatiable, and the sight of a piece of fesh rendered him: quite wild: he swallowed entire masses of a pound weight, and never refused any thing, devouring even that portion which he had just before been obliged to disgorge ;--no sort of meat was rejected by him; thc carcases of other birds of prey, and even of another griffard, which I had been dissecting, were indiscrimi. nately devoured.

. While these birds are perched, they utter from time to time a shrill piercing cry, mixed with a hoarse melancholy note, which is heard to a vast distance ; and so lofty is their flight, that they often disappear from view while their cry is still sufficiently audible.

.. I first met with this bird in the country of the Great Namaquois, about the 28th degree of south latitude, on the banks of the Great River. They became more frequent as I advanced towards the tro. pic, but are not to be found in Cafraria. They were probably at onc time to be seen as far south as the Cape : but, as the colory has increased, all the larger birds and quadrupeds, those especially which require a considerable tract of country for their subsistence, have been forced into the desart by civilized man a more potent de stroyer than themselves.'

The Oricou. . This vulture, like the other species of the genus, is an inhabit. ant of the mountains, in the caverns of which these birds have their nests; there they pass the night, and the rest of the day which is not devoted to procuring food. At sun-rise, they may be seen in great numbers perched on the crags before their dwellings, and forming a long irregular line, extending the whole length of a chain of mouotains. The feathers of their tails are worn by rubbing against the rock; whereas the eagles, being much less accustomed to walking, and perching also on trees, preserve theirs more entire. The vul. tures are also obliged to press their tails forcibly to the ground, and run a few steps before they are able to take wing from a level surface : but, notwithstanding this apparent difficulty of commencing their fight, when once raised from the ground they exhibit prodigious sirength and command of wing, and they ascend to such a height as totally to disappear from sight. It is not easy to imagine how these birds, at this vast elevation, are themselves able to perceive what is passing on the ground, to discover the animals on which they prey, and to precipitate themselves almost instantaneously on à cara case : yety if a hunter kills any animal too large for him to carry home, and departs for assistance, he is certain of finding, on his re.

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turn after a very short interval, that it has been almost entirely de. voured by a troop of vultures, not one of which was within sight a few minutes before.

• I have myself often experienced, to my cost, this surprising ac. tivity of the vultures, and other voraciou3 carnivorous birds. The first proof which I had of it was while labouring under a scarcity of provisions; and consequently the lesson impressed itself the stronger on my memory. I had been fortunate enough to kill thrée zebras'; and, satisfied with my success, I returned to my camp, which was at the distance of about a league, to give orders for a waggon to be sent for the game. My Hottentots, more knowing than myself, told me that it would be to no manner of purpose, as the rebras, would be devoured before we could reach them. We set out notwithstanding; and, on approaching the spot, saw the air almost filled with vultures; multitudes of them had alighted on the ground; the zebras were already devoured, nothing being left but the great bones, and the vultures kept still arriving every moment from all quarters, composing a vast llock of probably a thousand individuals. Being desirous of witnessing the great and rapid concourse of these birds, I one day concealed myself in a thicket, after having killed a large antelope, which I left on the spot where it fell : in an instant, some ravens made their appearance, hovering over the animal, and croaking loudly; a few minutes collected a flock of kites and buzzards ; a moment afterward, on looking up, I perceived some birds at a prodigious height, wheeling precipitately towards the carcase; I immediately recognized them for vultures, which seemed to have been let loose from the upper world.--As soon as the foremost had pounced on the animal, I came from my hiding place; on which they heavily took wing, and rejoined their companions; the number of whom was increasing from every direction, apparently rushing from the clouds to share the booty:' . We shall gladly receive additional numbers of this beautiful and entertaining work. www.and Art. XIV. Untersuchungen über Pathogenie, oder Einleitung in die

Mediziaische Theorie ; i. e. An Inquiry concerning the Origin of

Diseases, or an Introduction to the Theory of Medicine. By ; A. ROSCHLAUB, Public Teacher of Medicine at Bamberg.

Part I. 8vo. pp. 349. Frankfurt. 1798. SINCE the Brunonian controversy awakened the physicians of

the Continent from the dream of the humoral pathology, (an event which we duly noticed in a former Appendix,) we have observed many agreeable proofs of the very active spirit of inquiry by which that long slu'mber has been succeeded. Almost every university and medical school ha's furnished inaugural dissertations from its students, and volumes from its professors, on the philosophy of living nature. .

Among the latter, the performance before us, as far as we can judge from this first volume, promises to deserve to be

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numbered as one of the most elaborate. In the present part, a large space is occupied by verbal criticism and controversial explanations. When the other promised two parts appear, we shall probably present our readers with a summary of the whole.

We can enter farther into the following (though likewise an unfinished) work, which belongs to the same class.

ART. XV. J. C. REIL, Lebrer zu Halle über die Erkenntniss und

Kur der Fieber ; i. e. Professor Reil on the Knowlege and Treat· ment of Fevers. Part I. The general Doctrine of Fever. 8vo.

pp. 580. Halle. 1797. The work of which this is the commencement must doubt1 less be acceptable to every reflecting physician. · Dr. Reil proposes nothing less than to banish hypothesis altogether out of the doctrine of fever, and to found the treatment solely on an experimental knowlege of the disease. This, probably, is the only way by which the truth can be attained, either in the present important department of the healing art, or in any other.

In order to enable our intelligent readers to judge how far Dr. Reil has fulfilled his intention, it would be necessary to give a detailed account of the 28 chapters into which this his first yolume is divided : but, as our limits preclude so extensive an analysis, we shall extract so much of the contents as will qualify the medical philosopher to judge how far the whole work is worth his study.

In referring, says the author, the individual phænomena of animal bodies, in a state of sickness or of health, to general laws, we come at last to the composition and form (or organization) of a peculiar matter, which we denominate animal substance. On composition and form, and their modifications, must the different modes of existence of an animal, the variations of his internal state, and therefore also his health and his diseases, ultimately depend. There are certain rules of form and composition which determine the health of individuals : but with the latter in itself we have no acquaintance. We only know it from its effects. The rules are as numerous as individuals. Disease is a deviation froin the rule of healthy forma and composition, by which the functions of the individual are injured. The former appear in nature and degree anomalous, and may be infinitely various: but we have no knowlege of that irregular chemical composition, by which the disturbance or injury is occasioned. It is only of the form or organization of the body, that anatomy gives us clear historical evidence ; though its ultimate causes, as dependent on the activity of a peculiar

substance,

substance, are unknown. We have, therefore, only a scientific - knowlege of diseases, arising from a lesion of form. Of the composition or mixtion of the body, and of all that results from it, we are entirely ignorant; and we cannot in course pretend to any scientific acquaintance with the diseases dependent on injured or altered composition. Our knowlege on this head is purely empirical. - Under this latter class of derangements, fever unquestionably ranks. Most probably, also, a fault in the composition of the solids and fluids is the cause of fever. Hence we can only have historical and no scientific knowlege on this subject :-with that, for the present, we must content ourselves and study fever empirically, according to its characteristics, its symptoms, its effects, and its remote causes. We must endeavour to in. troduce order into the chaos of febrile phænomena; to distin-guish the genera and species of fever, i. e. sets of symptoms constantly occurring together; and we must observe the relation of these genera and species to certain remedies. We must study complications and the counteraction of several fevers in one individual, with the consequent modifications of the powers of medicines, and thus discover the best mode of treatment.

In fevers, we can perceive nothing but the external cause, (and not this always,) together with the injury of the functions which are its last effect. These we arrange, according as they depart from the healthy, phænomena of the body, under the heads of excessive, altered, and defective actions of the deco. nomy. From these we infer correspondent lesions of the powers, and impute them, 1st, to an increased susceptibility with proportionally increased power; or, 2dly, to an increased susceptibility with a weakened power; or, 3dly and lastly, to a decrease of both susceptibility and power. ;. .

This being premised, we define fever to be a preternatural change in the animal power of an organ, unattended by any correspondent - sensible change of structure; the power being either unimpaired or weakened, with an increased susceptibility of those nerves and vessels which belong to the feverish organ. By the che. mico-animal processes, occasioned by this state, all the animal powers may be destroyed.."

Fever, therefore, pre-supposes a lesion of the powers of the feverish organ. This manifests itself by an increased susceptibility, as is seen in a too rapid action in proportion to the effect of natural stimuli: which is as much as to say that, in fever, the disturbed functions must arise from an internal disease resident in the feverish organ; which disease consists in a · permanently increased susceptibility. No foreign stimulus,

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the organ being healthy, can excite fever. The lesion of the animal powers in the feverish organ, together with the operation of natural stimuli, is quite sufficient to account for its injured functions ; and the assumption of preternatural stimuli, or inateries morbi, coursing about in the body, is therefore not only unnecessary, but for several reasons utterly erroneous.

After having assigned these reasons, which (we apprehend) will appear very satisfactory, the author proceeds in the developement of his theory.

Exalted or increased susceptibility, he informs us, may, in fever, be accompanied by a proportionally strong or by a diminished power; or else susceptibility and power may be both diminished together. In all the organs of the animal body, and particularly in those in which the vital power exerts itself most, we distinguish a two-fold exertion; namely, sus. ceptibility and power. Though both these faculties are consequences of the particular composition and structure of the matter of which the organs consist, experience teaches that they are in some respect independent on each other, and that one may be affected without the other. Children and hysterical persons are very susceptible, but have little strength. Lunatics, on the contrary, with weak susceptibility, have great power.

Each exertion of the vis vita is therefore in a degree inde. pendent, and can be modified without the other. The injured composition of animal matter may, as the cause of fever, sometimes most influence the susceptibility, sometimes the power; exalting one without the other, or weakening the other, or both at once. Hence we may assume a three-fold diseased modification of the feverish organs as the cause of fever, viz..

1. An increase of the susceptibility, with a proportionally increased power.

12. Increase of the susceptibility with decreased power.. • 3. Diminution or destruction of both faculties at once. .

These varieties of disordered vis vita we actually find in esperience; and they commonly manifest themselves by signs sufficient to enable us to distinguish the one from the other..

At an inferior degree of lesion of the composition of animal substance, the susceptibility only is exalted, without any injury to the power: the latter is strong in proportion, or stronger than in the natural state. The actions of the feverish organs are in their nature unaltered'; only that, in proportion to the stimuli exciting them, they follow too hastily. . .. :

At a greater degree of lesion, the animal faculties suffer more. The susceptibility is increased, but the power is im: paired. The actions of the affected organ follow more quickly

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