It has been a custom, sometimes expressly authorized by the constitution, for the president to delegate executive powers and prerogatives to persons selected by him in various parts of the country, especially where revolutionary uprisings threatened. There has usually been such a delegate of the government in the Cibao and often one in Azua. They are powerful officials, inasmuch as they are regarded as the direct representatives of the president and his administration, command the local military forces, and constitute the fountain-head of all local executive appointments. Nominations as delegates of the government have been preferably conferred upon provincial governors or upon the vice-president. The president is naturally anxious to repose such powers in one of his confidants, but political exigencies have sometimes obliged him to soothe one of his rivals with the distinction and remain on the qui vive thereafter. More than one governmental delegate has overthrown the president and established himself in power. Provisional presidents have been numerous in Dominican history. After a successful revolution the victorious general usually proclaimed himself president of a provisional government and until the constitution was again declared in force he and his ministers united executive and legislative power. How far the acts of such de facto governments were legally binding upon the Republic has been questioned in cases where obligations were imposed upon the country, but foreign governments in asserting their rights have paid little attention to such quibbles. The constitution provides that there shall be such executive secretaries as may be determined by law. They are currently referred to as ministers and their number has been fixed at seven, namely, (1) secretary of the interior and police (interior y policia); (2) secretary of foreign relations (relaciones exteriores); (3) secretary of finance and commerce (hacienda y comercio); (4) secretary of war and the navy (guerra y marina); (5) secretary of justice and public instruction (justicia e instruccion publica); (6) secretary of agriculture and immigration (agricultura e inmigracion); (7) secretary of public development and communications (fomento y comunicaciones). Communication between Congress and the executive departments is rendered easier than in the United States by the constitutional provision that the secretaries of state are obliged to attend the Congressional sessions when called by Congress. This right of interpellation has frequently been exercised. The secretary of the interior and police is at the head of an important department. He is the administrative superior of the provincial governors and the communal and cantonal chiefs. His position renders him the sentinel of the government for the detection of revolutionary movements.