We have at length disposed ourselves to the habit of tracing the cause of disease, by combining a number of minute, and often varying, symptoms. A practice which, if correct in its detail, can never but be accurate in its deductions. Relative to the Plague, however, whose very name distracts the timid, and appals even the courageous, our reasonings and our deductions are quite of a different description. Respecting its cause, all is conjecture. No experienced or well-informed practitioner has watched the bed of the sick; none has accurately examined the different appearances which the disease assumes in different persons, nor even in its different stages, in the same person. Scarcely any, it is believed, has been tranquil enough to hear patiently from the mouth of the sufferer an account of his sensations, which, recounted by a third person, never fail to vary. Where this malady appears, the physician and the priest, the pride of science and the security of faith, confident and boastful when the patient alone is threatened, are both equally alert in their efforts to escape. The ignorant and unreflecting Muslim, indeed, awe-struck, and resigned to the unalterable decree of Fate, hangs over the couch of his expiring relative. But the report, guided by prejudice, is likely to mislead, and the observation can be of little value when the sole sentiment is stupor. Thus the Plague remains almost destitute of a local habitation, though it have a name in nosology. Who can at this day determine, whether the pestilence mentioned by Thucydides be the same as that of Modern Egypt and Turkey? Or whether the epidemical diseases, which have for several centuries, at intervals ravaged different parts of the Turkish empire, have been all specifically the same? The Europeans frequenting the Levant, have written profound treatises on the plague, simply from having seen a quantity of dead bodies carried past the doors of their houses, which the double optics of fear have occasionally magnified from 500 to 10,000.