Questions are often asked as to whether it is not possible to increase the available water supplies by sinking fresh wells. Where it is a question of sinking a new well in the middle of a long waterless stretch, or where the object is to sink a fresh well near an existing salty one in order to obtain a drinkable quality of water (and these are the two most usual cases), success cannot be predicted with any certainty, even in the most likely looking spots. We must remember that though the present Arabs may be lazy, the older tenants of the desert were more active. We have only to look at the old mining centres to see this. The probability is that the old miners were just as much worried by the scarcity of water as we are to-day, and with the cheap convict labour then available we may rest assured that every attempt was made to increase the supply. And it is not probable that the Arabs will have allowed to fall into disuse any existing well on an otherwise waterless road, so that it is likely that most of the wells in the wadis remote from the mountains are at spots specially favourable which have been discovered by a laborious process of trial and error. Confirmation of this view is supplied by the failure of new wells sunk at considerable cost in likely-looking places, as for instance at Abu Rahal, where a well carried down to over sixty metres’ depth failed to find water. Where modern wells have obtained water, they have usually been sunk near to or on the site of existing wells, as for instance near the temple of Seti I and at the different mining centres; in these cases it has sometimes been found possible to increase the supply by going deeper. And with regard to obtaining sweet water by sinking new wells near to old salty ones, no success can be hoped for if the saltiness is due to a general salt-content in the surrounding rocks; the Mines Department well in Wadi Mellaha[119] yielded no better water than the Arab well in the same wadi, because the alluvium everywhere in the wadi contains abundance of salt. In some cases, it may be, the promotion of a more rapid flow would lead to a slight lessening in the salinity; but if a well becomes salt merely by evaporation resulting from stagnation, that very fact shows that it is not much used by the ordinary traveller; and moreover the rate of flow of the underground water is not as a rule sufficiently rapid to yield large supplies, even from wide excavations. In the south parts of the country, where the rainfall is greater, it is possible, nay, even likely, that many new wells could be sunk with success; but in these localities existing wells are more abundant and the necessity for new wells does not arise. =Rock Basins (Galts).=