_23rd._--This morning exceedingly cold. In going out, a man said to me, "Where are you going this cold morning?" People were all shivering, or wrapped up in their burnouses. Said is attacked with ophthalmia. Received a visit from an old Arab doctor. He says cattle are attacked with the plague, as well as men. He wrote me a receipt for the cure of _night_-blindness, which would cure it in one night. He says, in the neighbouring desert, towards the west, there is a small oasis of Arabs, who are called _El-Hawamad_--‮الحومد‬--who are always afflicted by night-blindness, which singular affection is called by them _Juhur_ (‮جُهُر‬). Mr. Jackson, in his Morocco, calls this strange disease _butelleese_. The Arabs of _El-Hawamad_ see perfectly well in the day-time. But I must mention, that I received an application for medicine from a person who is affected with the same strange kind of malady. The European physicians call this disease _Nyctalopia_ (Νυκταλωπια). I recently myself met with a case in London. But what is equally extraordinary, Captain Lyon (I think) mentions a case which he met with in The Desert, of a person who could see in the night-time but not in the day-time--a human owl. We conversed about other diseases in Ghadames. The principal, as before-mentioned, are ophthalmia and diarrhœa. There are two lepers; a few dropsical people; and, occasionally, small-pox and syphilitic diseases. There are, besides, various cutaneous affections. Dogs are known to go mad amongst the Arabs, but not very often. When mad, they are called _makloub_. The remedy is, when they bite people, the hair of the mad dog himself, rubbing it over the part bitten. Mussulmans are fond of this antagonistic idea, of the bane and the antidote being one and the same thing, for they preserve the dead scorpions to be applied to the sting of the living ones, and they aver it to be a certain cure. Quackery is the native growth of the ingenious as well as the whimsical and hypochondriacal ideas of men. In dropsy the native doctors cut the body to let out the water, as we do. * * * * *