This latter course had been adopted with the administration of justice in the capital, in which the consuls, according to a rule inviolably adhered to, might not interfere, and with the transmarine provinces then existing--Sicily, Sardinia, and the two Spains--in which, while the consul might no doubt exercise his -imperium-, he did so only exceptionally.

In the ordinary course of things, accordingly, the six fields of special jurisdiction-- the two judicial appointments in the capital and the four transmarine provinces--were apportioned among the six praetors, while there devolved on the two consuls, by virtue of their general powers, the management of the non-judicial business of the capital and the military command in the continental possessions.

Now as this field of general powers was thus doubly occupied, the one consul in reality remained at the disposal of the government; and in ordinary times accordingly those eight supreme annual magistrates fully, and in fact amply, sufficed.
For extraordinary cases moreover power was reserved on the one hand to conjoin the non-military functions, and on the other hand to prolong the military powers beyond the term of their expiry (-prorogare-).

It was not unusual to commit the two judicial offices to the same praetor, and to have the business of the capital, which in ordinary circumstances had to be transacted by the consuls, managed by the -praetor urbanus-; whereas, as far as possible, the combination of several commands in the same hand was judiciously avoided.

For this case in reality a remedy was provided by the rule that there was no interregnum in the military -imperium-, so that, although it had its legal term, it yet continued after the arrival of that term de jure, until the successor appeared and relieved his predecessor of the command; or--which is the same thing-- the commanding consul or praetor after the expiry of his term of office, if a successor did not appear, might continue to act, and was bound to do so, in the consul's or praetor's stead.