Dion Cassius (l. liii. p. 703-714) has given a very loose and partial sketch of the Imperial system. To illustrate and often to correct him, I have meditated Tacitus, examined Suetonius, and consulted the following moderns: the Abbe de la Bleterie, in the Memoires de l'Academie des Inscriptions, tom. xix. xxi. xxiv. xxv. xxvii. Beaufort Republique Romaine, tom. i. p. 255-275. The Dissertations of Noodt and Gronovius, de lege Regia; printed at Leyden, in the year 1731. Gravina de Imperio Romano, p. 479-544 of his Opuscula. Maffei Verona Illustrata, t. i. p. 245 etc.