This sophisticated and rationally designed central bureaucracy was supplemented by regional administrations. Under the T'ang the regional establishments were a source of trouble to the government. The Empire was divided into provinces, but the provincial administrations were superseded by Imperial Commissioners whenever an emergency arose. Later dynasties placed the provincial system on a more stable basis, which resulted in genuine and geographically sound regionalism. The provincial governments were replicas in miniature of the central; their heads might be regarded as appointive and removable satraps whose authority was a smaller reproduction of the power of the emperor. It was not until the Ming dynasty (A. D. 1368-1643) that the provinces took on their modern form. The provincial governments were a source of great strength to China in that they made possible a quasi-federal government. In the Ch'ing period no officer was eligible to a post in his native province;[9] this custom had considerable centripetal effect and offset the danger that populace and officials, united by common sympathies, might revolt or secede.[10] Another feature to be noted about the Chinese government under the Empire was the examination and civil service system. The T'ang dynasty provided for three major types of examination: (1) The _chü_ corresponded most closely to a modern academic degree, and allowed the candidate to qualify in any one of a number of subjects, including the classics, law, and mathematics. (2) The _hsüan_ was the special examination necessary for appointment to a post in the bureaucracy; it was both written and oral and included the personal history of the candidate. (3) The _k'ao_, an in-service examination, consisted of annual reports on the performance of all officers in the Empire. They were transmitted to the Bureau for Examination of Merits in the Ministry of Administrators on a schedule varying with the distance of the office from the capital. There were five points on which to report: virtue and justice; integrity and circumspection; equity and impartiality; diligence and activity; and one of twenty-seven special talents suitable to the particular office in question. The grades received on these reports determined the advancement or demotion of the officer, in accordance with an elaborate and exact schedule.[11] All three examinations provided the administrative form for the close relation between the government and the scholastic elite. The _chü_, with its emphasis on the classics, framed the content of all curriculums. The _hsüan_, with its oral examination and personal record, made the prospective candidate careful in observing the customs. The _k'ao_ kept up the morale and efficiency of the bureaucracy, while the ominous Tribunal of Censors was present to guard against abuse of the system. Every detail was precise, well ordered, explicit, to a degree that would delight present-day industrial personnel managers. Formulation was