On the subject of climate, therefore, I must conclude with the following observations:--First: That, as the diseases above mentioned are produced both in moist and dry countries, in those in the torrid and those in the temperate zone, they can neither be the offspring of moisture or drought, of heat or cold, of septics or antiseptics, but of something not yet discovered. Second: That, upon fair investigation, it does not appear, that ancient historians have been able to ascertain the origin of any plague whatever: they have universally ascribed it to the anger of the Deity, while their own pride would never allow it to have originated in any country with which they were connected. Third: It doth not by any means appear, that the climates of those countries, where the plague is known to be most common, are at all inferior to those already described, excepting the very circumstance of having the plague frequently in them: nay, indeed, that they are equally bad. Nobody will pretend to argue, that the climate of Asia Minor, of Greece, of the Morea, or of any of the countries most infected with the plague, was, or is, worse than that of _Catchou_ in Africa, already described; yet it is certain, that we have a number of testimonies that the plague has ravaged Asia Minor, while we have not one of its visiting _Catchou_. Ancient Greece, the Peloponnesus (Morea) and Asia Minor, were accounted healthy and fine countries; and modern travellers assure us, that they have not degenerated in this respect; yet these countries are desolated by the plague, while the unwholesome regions above described are entirely free from it, unless imported from some other quarter. To give this matter, however, as fair a discussion as possible, I shall here consider the account we have of the climate of Bassorah, given by the gentleman residing there in 1780; whose case, in the remitting fever, is given, Appendix, No. VI. “The overflowing of the Euphrates, and its waters stagnating in the desert, have always been accounted primary causes of epidemical diseases at Bassorah. The great floods from the melting of the snow on the mountains of Diarbekir, the ancient Assyria, happened in the year 1780, early in the month of May, when the heats in Persia and Arabia begin to be excessive. The desert, which reaches to the gates of Bassorah, is, for many miles, incrusted with a surface of salt; which, when mixed with the stagnated waters, and exposed to the sun, produces the most noxious effluvia. As early as the 25th of May, the town was surrounded by a salt marsh, the heated steam arising from which was, at times, almost intolerable; but the canal that runs through a great part of the city being filled with the bodies of animals, and all kinds of putrid matter; and, at low tides, all these substances exposed to the sun, made the air in the town scarce supportable; and, being totally destitute of police, the streets were in many places covered with human