On the 18th of May we carried out our long-intended second visit to the Wadi Gazâl, took impressions of all the Greek and Koptic inscriptions of the burial-place, and took away with us what appeared yet legible. We are now more sensible than before of the meaning of the summer-season in the torrid zone; the thermometer usually rises in the afternoon to 37° and 38° Reaumur; indeed, occasionally, above 40° in the shade. The glowing sand at my feet I often found to be 53°, and whatever is made of metal can only be touched with a cloth round it in the open air. All our drawings and papers are richly bedewed with pearly drops of perspiration. But the hot wind is the most annoying, which drives oven-heat in our faces, instead of coolness. The nights are scarcely more refreshing. The thermometer falls to 33° towards evening, and towards morning to 28°. Our only refreshment is continual Nile-baths, which, however, would be considered warm-baths in Europe. We have several times had storms with violent sand-filled hurricanes, and a few drops of rain. Yesterday a whirlwind beat down our tent, and at the same time our arbour of strong trunks and palm-branches fell upon us from its violence, while we were eating; the meal was scarcely eatable on account of the strong spice of sand. It would seem that violent gusts of wind are peculiar to this clime or country, for one often sees four or five high sand-pillars at the same time at different distances, dashing heavenward like mighty volcanoes. There are few serpents here; but a great number of scorpions, and ugly great spiders more feared by the natives than the scorpions. We therefore sleep on _anqarebs_ brought from the village, on account of these malicious vermin. LETTER XXIV. DONGOLA. _June 15, 1844._ Before our departure from Barkal, I undertook an excursion up the Nile into the district of the cataracts, which we had cut off in our desert journey. I also wished to learn the character of this part of the country, the only portion of the valley of the Nile which we had not traversed with the caravan. We went by water to Kasinqar, and remained there the night. From here arise wild masses of granite, which form numerous islands in the rivers, and stop the navigation.