About half-past four we reached our appointed camping place, at Aïn Oumast, one of the few wells of drinkable water found in the region we had now entered. In the coast zone it would appear that in ordinary years the rainfall is sufficient to enable the natives to raise grain crops wherever the soil is suitable for the purpose; but in the interior, cultivation is limited to the tracts that are capable of irrigation from the streams descending from the Great Atlas, or else to the immediate neighbourhood of wells. The ground around Aïn Oumast had borne a scanty crop of grain, and the rough surface, now baked hard by the sun, was not very comfortable for sleeping upon, even with the intervention of a mattress of cork shavings. For a short way before our arrival, the main chain of the Great Atlas had for the first time been in view, dimly apparent at a distance of some sixty miles; but as the sun declined towards the horizon, the outlines became clearer, and we naturally watched with increasing interest every feature of that mysterious range seen, even from a distance, by few civilised men, whose recesses we hoped to be the first to explore. We discussed eagerly the question whether some patches of lighter colour represented snow, or merely surfaces of whitish limestone rock; and, as usual, the only effect of discussion was to confirm each in the impression first formed, which it was impossible to verify or disprove unless, by viewing the range from the same direction under similar conditions at a later season, we could discover whether the appearances in question should have altered or disappeared. The _mona_ presented by the Kaïd or sheik of the place was naturally less profuse than that offered at Shedma, but yet abundant for the needs of our camp. As almost everywhere, save in the remoter valleys of the Atlas, green tea and a quantity of white sugar formed a main feature in the entertainment, and doubtless the most expensive to the poor people who had to provide it. The day had been warm, though not oppressive, the thermometer probably standing at about 80° Fahr. in the shade, and the fall of temperature during the night was very sensible. Even after the sun had risen on May 1—soon after five A.M.—the thermometer marked only 54° Fahr., but by six A.M. it reached 67°. The observation for altitude gave 1,132 feet (345·5 m.) above the sea; probably too low by fifty or sixty feet, owing to the local effect of radiation in depressing the temperature of the air in contact with the surface.