On the fourth day we ought actually to have been at the wells of brackish but, for the camels, drinkable water; but in order not to go too fast for Sheikh Ahmed, we halted at four o’clock, still about four hours’ distance from the wells. At last, towards mid-day, we left the great plain Bahr Bela ma, (river without water,) which joins the two days’ long mountain range of El Bab, into which we had entered from Korusko, and now neared other mountains. Till now we had had nothing but uniform sandstone rocks beneath and around us, and it was a pleasing circumstance when I perceived, from the high back of the camel, the first plutonic rock in the sand. I slipped down immediately from my saddle, and knocked off a piece; it was a grey green stone, of very fine texture, and without a doubt of granitical nature. The other mountains also were mostly composed of species of porphyry and granite, with which the red syenite, so much employed by the ancient Egyptians, as so extensively seen at Assuan, not unfrequently appears in broad veins. Farther into the mountains quartz predominated, and it was somewhat peculiar to see the snow-white flint veins peeping at different heights from the black mountains, and flowing streamwise down into the valley, where the white extended somewhat after the fashion of a lake. I took small specimens, also some of the various kinds of rock. After we had passed, crossing a little ravine, the little valley Bahr Hátab, (Wood River, by reason of the wood somewhat farther in the mountains), and another Wadi Delah, on the north side of the mountains, we came to the rock-gorge of E’Sufr, where we expected to find rain-water, to replenish our shrunken water-bags (_girbe_ pl. _geràb_). In this high mountain it rains in one month of the year, about May. Then the mighty basins of granite in the valleys are filled, and hold the water for the whole year. On this plutonic rock, there was some little vegetation to be seen, in consequence of the rain, and because the granite seems to contain a somewhat more fertile element than the sad-looking, brittle sand, composed almost wholly of particles of quartz. At Wadi Delah, which has water in the rainy season, we came to a long-continued row of dûm-palms, the rounded leaves and bushy growth of which makes a less crude impression than the long slender-leaved date-palms; the latter will not bear rain, and are therefore altogether wanting in Berber, while the dûm-palms occur at first very singly in Upper Egypt, and become more numerous, more full, and more large, the farther they reach southward. When their fruit drops off unripe and dry, the little eatable matter about the stone tastes like sugar; when ripe, the yellow wood-flavoured meat may be eaten; it tastes well, and some fruits had an aroma like the pine-apple. They sometimes grow to the size of the largest apples.