1. M. de Montesquieu (Considerations sur la Grandeur et la Decadence des Romains, c. 17) Supposes, on the authority of Orosius and Eusebius, that, on this occasion, the empire, for the first time, was really divided into two parts. It is difficult, however, to discover in what respect the plan of Galerius differed from that of Diocletian.