These considerations, it may be acknowleged, do not carry conviction; but too many local diseases are yet unexplained, to leave any wonder if the cause of this should yet remain problematical.

Plague.

All the improvements in the art of healing which modern Europe can boast as its own, are the result of more frequent experiment, and more patient and minute investigation, than existed in the antient.

To conjecture ingeniously is a matter of small effort, and in treating of what is properly the object of experiment, it is not only of no value, but often of dangerous result. But it is suited to the indolence of the human mind, and flattering to personal vanity, which delights to perform much by a single energy. Hence, an hypothesis supported by some insulated fact, perhaps only by specious error, is often advanced with warmth, and the most important considerations militating against it, are forgotten, or warped to serve the purpose of the inventor. Thus the increase of the Nile was once confidently attributed to the Etesian winds; and the malady which has so often almost depopulated Kahira, is still by some imagined to proceed from the putrid deposition of its waters.

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.

The facts that appear chiefly to be ascertained relative to the plague, are, 1st, That the infection is not received but by actual contact. In this particular, it would seem less formidable than several other disorders. 2. That it is communicated by certain substances, by others not, as by a woollen cloth, or rope of hemp, but not by a piece of ivory, wood, or a rope made of the date tree; nor by any thing that has been completely immersed in water. It would appear from the report of the Kahirines, that no animal but man is affected with this disorder; though, it is said, a cat passing from an infected house, has carried the contagion. 3. That persons have often remained together in the same house, and entirely under the same circumstances, of whom one has been attacked, and died; and the others never felt the smallest inconvenience. 4. That a person may be affected any number of times. 5. That it is more fatal to the young than the old. 6. That no climate appears to be exempt from it; yet, 7. that the extremes of heat and cold both appear to be adverse to it. In Constantinople it is often, but far from being always terminated by the cold of winter, and in Kahira by the heat of summer; both circumstances being, as may be conjectured, the effect of indisposition for absorption in the skin, unless it be supposed that in the latter case, it may be attributed to the change the air undergoes from the increase of the Nile.

The first symptoms are said to be thirst; 2. cephalalgia; 3. a stiff and uneasy sensation, with redness and tumour about the eyes; 4. watering of the eyes; 5. white pustules on the tongue. The more advanced symptoms of buboes, fœtor of the breath, &c. &c. are well known; and I have nothing authentic to add to them. Not uncommonly, all these have successively shewn themselves, yet the patient has recovered; in which case, where suppuration has had place, the skin always remains discoloured, commonly of a purple hue.—Many who have been bleeded in an early stage of the disorder, have recovered without any fatal symptoms; but whether from that or any other cause, does not appear certain. The same operation is reported to have been commonly fatal in a late stage. It is said that embrocating the buboes continually with oil has sometimes wrought a cure; but this remedy is so difficult and dangerous for the operator, that it would appear experiments must yet be very defective. The natives of Kahira are too supine to seek for any remedy, and too bigoted to avoid the danger.