The thermometer about sunset stood at 72° Fahr., while in the water flowing beside our camp it marked but 62°. At 1 A.M., when we had concluded our nightly task in laying out our plants, it had fallen to 52°, and rose only to 57° an hour after sunrise, when the barometer was recorded, and gave an estimated altitude of 1,141 feet (347·8 m.), or almost exactly the same as that of Aïn Oumast. The coolness of night temperature throughout this region of Northern Africa doubtless contributes to make the climate not only healthy but favourable to human activity; and it was impossible for us not to speculate at times on a possible, though remote, future, when this may become the home of a prosperous and progressive community. Early rising does not always mean an early start, and many delays occurred on the morning of May 2, before our caravan was fairly under way at about 9 o’clock. On leaving our encampment, we perceived, on rising ground close at hand, the remains of an ancient town, with stone houses, for the most part in ruins, but some of them still inhabited, and a _kasbah_ or castle of somewhat imposing appearance. We failed to obtain any information as to these buildings, which may probably be of considerable antiquity. It must be remembered that throughout the portion of Marocco inhabited by an Arab population permanent houses are unknown, excepting in the coast towns and the royal cities of Marocco, Fez, and Mekines. The country people live in _douars_, which are merely groups of rude dwellings, half hovel half tent, usually formed of branches, over which a piece of camel’s hair cloth is stretched, and leaving no wreck behind when choice or necessity leads their inhabitants to remove from one spot to another. Even the Governor’s _kasbah_, though often a pile of large dimensions, rarely survives a single generation. The great wall and massive towers surrounding it, as well as the building itself, are constructed of unbaked bricks or of blocks of mud half dried in the sun; and save in cases where a son succeeds his father in power, the custom of the country is to level the whole structure to the ground on the death or removal of the occupant. A few seasons complete the work, and nothing remains but a few mounds of clay to mark the site. Thus it happens that in a country of which the greater part is naturally fertile, the stranger may travel long distances without perceiving a trace of human habitations, or any other buildings than the _zaouias_ and _koubbas_, which are scattered over the country at unequal intervals. By these names are designated the tombs of persons, who, when alive, attained a reputation for sanctity, differing only in the rank which they hold in local estimation. The person over whose remains a _zaouia_ is constructed may be regarded as the patron saint of the tribe or province, while the _koubba_ marks the resting-place of a saint of less renown.