If any medical professor should chance to advert to them, the writer is too conscious of the superficiality of his own knowlege not to perceive, that little satisfaction will be derived. But persuaded, that the art of healing, even at this day, abounds little less in experiments than in the age of one of its brightest ornaments, who makes the confession, he is induced to believe, scarcely any fact relative to it, or any experiment, faithfully narrated, can be wholly destitute of its use. _Psorophthalmia._ It is remarked that in Egypt, but particularly in Kahira, the blind, and those who have defective vision, bear a large proportion to the number of the inhabitants. The fact observed, which cannot be disputed, has been explained in various ways. It has by some been considered as proceeding from the habitual use of rice. By others, as the effect of the subtle dust which floats in the air. Even the water of the Nile has been supposed to co-operate at least, if not to be the sole agent, in producing this remarkable disease. To explore the origin of this or any other malady, all its appearances must first be accurately noted. The ophthalmia of Egypt leads us through a diversity of symptoms, from slight inflammation and defluxion, to the total and irrecoverable blindness occasioned by opacity of the Cornea. To enumerate them all correctly, and compare them in a variety of cases, must be the task of an oculist long resident on the spot, and accustomed to numerous patients. A transient observer, however diligent in his inquiries, may more easily prove the falsehood of the assigned causes, than trace the real one. The Nile water, it may be supposed, when taken into the stomach, can have no effect on the eyes, but by first altering the state of the fluids, into which it, as well as other aliments, is gradually converted. Whether from mineral or vegetable impregnations, it could never operate solely on the eyes, without affecting any other part of the animal economy. The effect of opium is seen on the blood and muscular fibres; of mercury on the glands and lymphatics; of cantharides on the nerves: and too great a portion of these, taken into the body, may have a pernicious effect on the eyes, but always through the medium of other parts. The whole _materia medica_, perhaps, furnishes no drug or mineral that is known, when taken into the stomach, to have a local and partial effect on the eyes. Such an effect is even irreconcileable with the general and constantly observed operation of all remedies applied to the human body. Besides, if the injury were solely or even in part to arise from the use of the Nile water, all those who drink it must be equally affected, allowing for the different degree of firmness in the stamina of each. But certain orders of men are rarely attacked by this disease, and they too who are continually using the river water both internally and externally.