In Roman times water-stations appear to have been maintained at frequent intervals on the desert roads between the oases and the Nile Valley, and a great development of the water-supply took place. After the Arab invasion, however, no attention seems to have been given to irrigation works, the wells, owing to silting, becoming gradually choked up. As the result of this neglect the water-supply diminished to such an extent that a large portion of the population was compelled to emigrate to the Nile Valley, and even the remaining inhabitants were scarce able to raise sufficient supplies for their maintenance. Within the last fifty years a considerable number of new wells have been made by means of simple hand-boring appliances sent out by the Egyptian Government; most of the new bores have been very successful, but latterly, through want of effective supervision, a great deal of harm has been done by promiscuous boring. Moreover, a very large amount of water is wasted owing to the wells not being fitted with regulating and closing appliances; the water, when not required for irrigation, continues to run, finding its way to the low-lying lands, and forming swamps which furnish ideal breeding-grounds for fever-carrying mosquitoes. Within the last year or two this part of Egypt has received renewed attention; extensive boring operations and land reclamation works have been commenced, and the oasis of Kharga has been brought into railway communication with the rest of Egypt. The floor-level of the oases varies considerably, but in general the cultivated lands lie between 30 and 120 metres above sea-level. The exact area under cultivation is only known very approximately, but it is certain that with an increased water-supply it could be very much augmented. The existing water-supply is totally insufficient to irrigate the available lands, and such portions of the latter as are tilled are generally left fallow in alternate years, and in many cases are only under crops once every four or five years. Now that an attempt is being made to restore the oases to their former prosperity, the question of ownership of land has become of the greatest importance, and it is one bristling with difficulties. As a general rule the wells are owned collectively, the different proprietors having the right to utilize the flow for periods corresponding to the extent of their holdings in the well. Individual shares may amount to as much as one-third or one-half of the well, or be only the merest fraction; in the latter case the small holders combine so as to obtain control of the flow for an appreciable period. Frequently the whole of the land irrigated by a well is cultivated collectively, the crop on reaping being divided among the owners in portions corresponding to their shares of the water. The question of ownerships is further complicated by there being persons who own water but no land, and by others who claim land but own no water.