_Nyctalopia, Hemeralopia, or Night-blindness, called by the Arabs Butelleese; and its Remedy_.
During my residence at Santa Cruz, I had a cousin with me who was afflicted with this disorder. When the sun sat his blindness came on, and continued till the rising sun. This youth was so afflicted, during a month, with this disorder, that he could scarcely see his way with a candle in his hand, so that it was quite painful to see him groping about. An Arab of the Woled Abbusebah Kabyl, who retain much of the science and art of their ancestors, and whose prosperity I had promoted at Santa Cruz, by facilitating his commercial adventures, communicated to me a simple remedy for this disorder; I put no faith in it, for it was so simple that I was disposed to think it an illusion. He called on me, however, repeatedly, and finding I had not applied it, he brought it one morning himself, and urged me to try it, I did so; and that same evening the eyes of the youth were almost well, and his sight was 333 completely restored the following night. This ophthalmic affection, in an Arabic translation of Hippocrates, is called _Butelleese;_ another translation of ancient date calls it _Shebkeret:_ the name, however, by which it is known at the present day in Africa, is _Butelleese:_ the Latins called it _Lusciosus_, which word denotes precisely the disease, viz. one who sees imperfectly in the morning and evening twilight, but whose vision is clear at broad day-light. _Lusciosus ad lucernam non videt. Vesperi non videre quos lusciosos appellant_. Plaut. Mil. Gl. ii. 3.
This ophthalmia has been by some denominated _hen-blindness_, from the circumstance of hens' eyes being thus affected, when they are unable to see to pick up small grains in the dusk of the evening. I have frequently seen fowls thus affected soon after going to sea, from the coast of Africa, after which they decline and grow sick. A quantity of small gravel should be spread in their coops at sea, which prevents this disorder, and will sometimes cure it. At the commencement of this complaint, the circumstance that first engages the patient's attention is the dimness of his eye-sight at twilight: the nocturnal dimness of vision was such, in the instance before-mentioned, that the youth could scarcely see, even with a candle in his hand, which he described, as seen by him, as if it were misty, or as glimmering in a thick fog. There was no external disfiguration visible in the eyes, but they appeared as usual. 334 What the cause of this disorder was I am unable to say; but I have often suspected that it was contracted from the shining of the sun on the white terras of the house where my cousin used to go of a morning to shoot _tibeebs_, a bird somewhat resembling the European sparrow. This youth was rather of a weak or delicate constitution. I did not repeat the above remedy, as the boy's eyes continued well, without any defect in the vision at any time of the day or night, till seven-and-twenty days had elapsed, when the disorder returned. I procured the remedy again, and he took it; it had the same effect as before; he took it again, and then continued well for a month. It again returned a third time, and was cured by one single administration, after which it entirely disappeared, and never returned. Some time after this, I was informed that the British fleet in the Mediterranean was affected with this disorder; that one-tenth, or more, of the crews of our ships had laboured under it; and, on my return to England, I was urged to represent to His Majesty's ministers, that I had an infallible remedy for the disorder. I was referred to Doctor Harness, of the Transport Board. I waited on the Doctor, and afterwards corresponded with him. He appeared very desirous of knowing the remedy; but he was not at liberty to grant me any remuneration for it. I, however, offered to discover it, on being reimbursed the sum which the remedy cost me, 335 on experimental proof being produced of its infallibility; which proposition was rejected by the Transport Board in August, 1812, who informed me at the same time, that the Lords Commissioners of the Admiralty did not judge proper to grant the sum required by me for the discovery of the remedy for Nyctalopia, which, I should add, was between 500_l_. and 600_l_. The remedy, therefore, remains a secret to this day.