During 1949 the Arabian American Oil Company resumed and prosecuted with vigour the work begun some ten years earlier of exploring the eastern reaches of the Province of al-Hasa. It was thought desirable that information on the geography and inhabitants of the region should be accumulated and embodied in a comprehensive survey. Since agreement had not then been reached by the Governments of Saudi Arabia, Qatar, and Abu Dhabi regarding their common boundaries, special attention was given to the territory of Saudi Arabia abutting on the Peninsula of Qatar as well as its territory abutting on the hinterland of Abu Dhabi in the region of the Trucial Coast. (Reports prepared for the Arab American Oil Company by its own research division and published with the consent of SAUDI ARAMCO, William Mulligan and F. S. Vidal).