e means of pursuit and revenge. And when, after a vast expense of
time and labor, a new armament was launched into the water, the Imperial
troops, unaccustomed to that element, were easily baffled and defeated
by the veteran sailors of the usurper. This disappointed effort was
soon productive of a treaty of peace. Diocletian and his colleague, who
justly dreaded the enterprising spirit of Carausius, resigned to him
the sovereignty of Britain, and reluctantly admitted their perfidious
servant to a participation of the Imperial honors. But the adoption
of the two Caesars restored new vigor to the Romans arms; and while
the Rhine was guarded by the presence of Maximian, his brave associate
Constantius assumed the conduct of the British war. His first enterprise
was against the important place of Boulogne. A stupendous mole, raised
across the entrance of the harbor, intercepted all hopes of relief. The
town surrendered after an obstinate defence; and a considerable part of
the naval strength of Carausius fell into the hands of the besiegers.
During the three years which Constantius employed in preparing a fleet
adequate to the conquest of Britain, he secured the coast of Gaul,
invaded the country of the Franks, and deprived the usurper of the
assistance of those powerful allies.

Before the preparations were finished, Constantius received the
intelligence of the tyrant's death, and it was considered as a sure
presage of the approaching victory. The servants of Carausius imitated
the example of treason which he had given. He was murdered by his first
minister, Allectus, and the assassin succeeded to his power and to his
danger. But he possessed not equal abilities either to exercise the
one or to repel the other. He beheld, with anxious terror, the opposite
shores of the continent already filled with arms, with troops, and with
vessels; for Constantius had very prudently divided his forces, that
he might likewise divide the attention and resistance of the enemy. The
attack was at length made by the principal squadron, which, under the
command of the praefect Asclepiodatus, an officer of distinguished merit,
had been assembled in the north of the Seine. So imperfect in those
times was the art of navigation, that orators have celebrated the daring
courage of the Romans, who ventured to set sail with a side-wind, and
on a stormy day. The weather proved favorable to their enterprise. Under
the cover of a thick fog, they escaped t