The name and use of the _indictions_, 170 which serve to ascertain the chronology of the middle ages, were derived from the regular practice of the Roman tributes. 171 The emperor subscribed with his own hand, and in purple ink, the solemn edict, or indiction, which was fixed up in the principal city of each diocese, during two months previous to the first day of September. And by a very easy connection of ideas, the word _indiction_ was transferred to the measure of tribute which it prescribed, and to the annual term which it allowed for the payment. This general estimate of the supplies was proportioned to the real and imaginary wants of the state; but as often as the expense exceeded the revenue, or the revenue fell short of the computation, an additional tax, under the name of _superindiction_, was imposed on the people, and the most valuable attribute of sovereignty was communicated to the Prætorian præfects, who, on some occasions, were permitted to provide for the unforeseen and extraordinary exigencies of the public service. The execution of these laws (which it would be tedious to pursue in their minute and intricate detail) consisted of two distinct operations: the resolving the general imposition into its constituent parts, which were assessed on the provinces, the cities, and the individuals of the Roman world; and the collecting the separate contributions of the individuals, the cities, and the provinces, till the accumulated sums were poured into the Imperial treasuries. But as the account between the monarch and the subject was perpetually open, and as the renewal of the demand anticipated the perfect discharge of the preceding obligation, the weighty machine of the finances was moved by the same hands round the circle of its yearly revolution. Whatever was honorable or important in the administration of the revenue, was committed to the wisdom of the præfects, and their provincia. representatives; the lucrative functions were claimed by a crowd of subordinate officers, some of whom depended on the treasurer, others on the governor of the province; and who, in the inevitable conflicts of a perplexed jurisdiction, had frequent opportunities of disputing with each other the spoils of the people. The laborious offices, which could be productive only of envy and reproach, of expense and danger, were imposed on the _Decurions_, who formed the corporations of the cities, and whom the severity of the Imperial laws had condemned to sustain the burdens of civil society. 172 The whole landed property of the empire (without excepting the patrimonial estates of the monarch) was the object of ordinary taxation; and every new purchaser