is not unlikely that an equally irritable ftate of brain may exift in many infirm people, rendering them in a peculiar manner fubject to the attack of fever. But in general it has appeared to me, that men are at least as fufceptible of typhus as women, if equally expofed to contagion, and that the disease in them is more violent, and attended with greater danger.

On the other hand, temperance, and even ftrict abftinence with regard to the ufual modes of living, have, in numberless instances, in times of peftilence and contagion, proved fovereign prefervatives; and, when the prevailing disease has occurred under fuch circumftances, it has been rendered comparatively mild and fafe. In hot climates, negroes, women, water-drinkers, and others who obferve great temperance of living, are far lefs fubject to be attacked by the endemic fever of the country, than those in the reverfe circumftances. The Frenchman, who lives much on vegetables, and drinks fparingly of ftrong liquors, escapes much better the ravages of the yellow fever, than the Englishman, who eats and drinks as he had been accustomed to do in northern regions. Timoni, in his account of the plague at Conftantinople, obferves,

that the Armenians, who live chiefly on vegetable food, were far lefs difposed to the disease than other people*. M. Defgenettes obferves, with regard to the plague or pestilential fever in Egypt, that women, young perfons, and infants at the breast, escaped infection more than the most robuft ment. Of the plague at Moscow De Mertens obferves," that the young and robust were more liable to become infected than elderly and infirm perfons; pregnant women and nurses were not fecure from its attacks. Children under four years of age were much lefs readily infected, but, when they were, they exhibited the worft fymptoms.'

1

"Almost all the first victims of the yellow fever," fays Dr. Dryfdale, "were perfons habituated to the immoderate use of ardent spirits; and it is a melancholy truth, that very few of thefe unfortunate creatures could be refcued from death by all the powers of medicine."-" In drinkers of ardent fpirits, the fever was excited not only with more facility, but was attended alfo with almost irrefiftible violence and malig

* "Armeni omnium nationum minimè ad peftem funt difpofiti obfervo illos pauciffimis uti carnibus: cepis, porris, alliis, vinoque maximè utuntur."

+ Hiftoire Med. de l'Armee de l'Orient,, p. 108.

nity. Even a moderate but unusual indulgence in thefe liquids foon roufed the difeafe into action. A glass of wine would occafion a headach in those who were much expofed to the exhalations of the fick, or to the air of infected places; and for a confiderable time in September, half that quan tity would affect me in a fimilar manner*. -It is fcarcely neceffary to remark on the tendency of fpirituous liquors to occafion increased vafcular action in the brain: and we fee readily, upon the hypothefis here contended for, a reafon why the use of them fhould both give a predifpofition to fever, and aggravate all its fymptoms, at least during the most active stages of the disease.

* See Coxe's Med. Mufaum, No. 1, p. 30.

Sect. VIII.---Of Fever as compared with the Phrenitis of Authors.

FROM what has been now faid, it must appear, I think, at least probable, that fever confifts effentially in an inflammatory action going on in the veffels of the brain; in other words, that it is nothing more nor lefs than a fpecies of phrenitis or topical inflammation of this organ. This will appear ftill more evident from a comparison of the fymptoms, caufes, and treatment of the two affections.

The term phrenitis has been fo vaguely ufed by writers, that it is not always easy to afcertain the sense in which they employ it. The antients appear generally to have used it fynonymously with delirium. The Greeks, Celfus fays, called every delirium or alienation of mind by this denomination. In fome of the works, however, afcribed to Hippocrates, it obviously denotes more than a mere fymptom, and is fpoken of as a primary affection, diftinct from delirium-"vehementi infania detenti, tremuli, cum crebra

fputatione, metus eft ne phrenetici evadant*" here the term appears to be employed in nearly the fame fenfe that we use it at prefent, namely, to denote an acute topical affection of the brain, though it is not directly afcribed to inflammation.

Some even of the moderns have confidered phrenitis as an affection of the brain diftinct from inflammation. Willis thought it depended upon a phlogofis or inflammation of the animal fpirits,-not of the fubftance of the brain, the inflammation of which, he fuppofes, would be more likely to occafion foporous diseasest. Selle, in his Rudimenta Pyretologia, places phrenitis among the Atacta or nervous diforders, and confiders it as exifting without inflammation, as proved, he fays, by diffection, and by the opinion of Hippocrates. In general, however, modern writers agree in confidering phrenitis as a topical inflammation of the brain. or its membranes, and it is in this fenfe that I shall here employ it.

Phrenitis has by fome authors been divided into two fpecies, the true (phrenitis vera),

* Coaca Pranotiones, fect. 2.

+ De Delirio, cap. x.