intermittent fever, assigned the miasma of marshes as the origin of the disease, while he makes no mention of animal malaria in his definition of any of the forms of fever; and as this author superseded all former authorities, by becoming the great authority of the age, few of his successors are acquainted in the slightest degree with the writings anterior to his period: whence it has happened that the numerous and invaluable facts observed and recorded by his predecessors, relative to the cause of fever, have been disregarded until they have become wholly unknown. To cite the antient and the more modern authorities who have observed and recorded the influence of animal malaria in the product of plague, would be to enumerate every distinguished writer, from Pliny and Diodorus Sicculus, down to Galen, from Galen to Mead, and from Mead to Pringle. In assigning the reason why Grand Cairo, in Egypt, is the birth-place and the cradle of the plague, Mead states that this city is crowded with vast numbers of inhabitants, who live not only poorly, but nastily; that the streets are narrow and close; that the city itself is situated in a sandy plain, at the foot of a mountain, which keeps off the winds that might refresh the air; that consequently the heat is rendered extremely stifling; that a great canal passes through the midst of the city, which at the overflowing of the Nile is filled with water; that on the decrease of the river, this canal is gradually dried up, and the people throw into it all manner of filth, carrion, offal, and so on; that the stench which arises from this, and the mud together, is intolerably offensive; and that, from this source, the plague constantly springing up every year, preys upon the inhabitants, and is stopped only by the return of the Nile, the overflowing of which washes away this load of filth: that in Ethiopia the swarms of locusts are so prodigious, that they sometimes cause a famine, by devouring the fruits of the earth, and when they die, create a pestilence, by the putrefaction of their bodies; that this putrefaction is greatly increased by the dampness of the climate which, during the sultry heats of July and August, is often excessive; that the effluvia which arise from this immense quantity of putrefying animal substance, combined with so much heat and moisture, continually generate the plague in its intensest form; and that the Egyptians of old were so sensible how much the putrefaction of dead animals contributed towards breeding the plague, that they worshipped the bird Ibis, from the services it did in devouring great numbers of serpents, which they observed injured by their stench when dead, as much as by their bite when alive.