Our middle Sulphur-hill differs essentially from the other two deposits, the northern near Makná, and the southern near El-Wijh, in being plutonic and not sedimentary. One would almost say that it smokes, and the heat-altered condition of the granite, the greenstone, and other rocks, looking as if fresh from a fire, suggests that it may be one of the igneous veins, thrown westward by the great volcanic region, El-Harrah. In parts it is a conglomerate, where a quantity of quartz takes the place of chalk and gypsum. Other deposits are iron-stained and have the appearance of the decomposed iron pyrites which abounds in this neighbourhood. Usually the yield is the normal brimstone-yellow, yet some of the beds are deep red, as if coloured by ochre or oxide of iron: this variety is very common in the solfataras of Iceland; and I have heard of it in the Jebel Mokattam, near Cairo. The colour is probably due to molecular changes, and possibly shows greater age than the yellow. M. Philipin was directed to take charge of Sergeant Mabrúk, the nine quarrymen, and the Bedawi owners of two camels to carry his boring-irons, forge, and water from El-Muwaylah. I advised him to dig at least forty feet down all round the pyramid, wherever surface-indications attracted notice: old experience had taught me that such depth is necessary before one can expect to find brimstone beds like those of Sicily. The borings brought up sulphur from fourteen metres; beyond these, six were pierced, but they yielded nothing. In and around the pyramid M. Philipin sank five pits; the northernmost shaft, half-way up the hill, gave crystals of the purest sulphur. If the depth of the deposit be not great, the surface extent is. The pyramid evidently forms the apex of a large vein which strikes north-south. The field consists of this cone with its dependencies, especially the yellow cliffs to the north and the south, facing, in the latter direction, a large plain cut by the Wady el-Kibrít. Moreover, a vein of the red variety, about three kilometres long by twenty-five to thirty metres broad, lies to the south-east near a gypsum hill: the latter also yields the crystallized salt which so often accompanies sulphur, and heaps of gigantic half-fossilized oyster-shells are strewed about it. M. Philipin here remained sixteen days (February 18--March 5), during our absence in the East Country; on return we found our good blacksmith much changed for the worse. Whilst in hard work he had been half-starved, the Jeráfín Bedawin of the neighbourhood having disappeared with their flocks; he had been terribly worried by the cameleers, and he had been at perpetual feud with the miserable quarrymen. I never saw a man less fitted to deal with (two-legged) "natives." The latter instinctively divined that he would rather work himself than force others to work; and they acted accordingly.