sia, had been repaired and strengthened; and as long as
Licinius remained master of the sea, the garrison was much less exposed
to the danger of famine than the army of the besiegers. The naval
commanders of Constantine were summoned to his camp, and received his
positive orders to force the passage of the Hellespont, as the fleet
of Licinius, instead of seeking and destroying their feeble enemy,
continued inactive in those narrow straits, where its superiority of
numbers was of little use or advantage. Crispus, the emperor's eldest
son, was intrusted with the execution of this daring enterprise, which
he performed with so much courage and success, that he deserved the
esteem, and most probably excited the jealousy, of his father. The
engagement lasted two days; and in the evening of the first, the
contending fleets, after a considerable and mutual loss, retired into
their respective harbors of Europe and Asia. The second day, about noon,
a strong south wind [108] sprang up, which carried the vessels of Crispus
against the enemy; and as the casual advantage was improved by his
skilful intrepidity, he soon obtained a complete victory. A hundred
and thirty vessels were destroyed, five thousand men were slain, and
Amandus, the admiral of the Asiatic fleet, escaped with the utmost
difficulty to the shores of Chalcedon. As soon as the Hellespont
was open, a plentiful convoy of provisions flowed into the camp of
Constantine, who had already advanced the operations of the siege.
He constructed artificial mounds of earth of an equal height with the
ramparts of Byzantium. The lofty towers which were erected on that
foundation galled the besieged with large stones and darts from the
military engines, and the battering rams had shaken the walls in several
places. If Licinius persisted much longer in the defence, he exposed
himself to be involved in the ruin of the place. Before he was
surrounded, he prudently removed his person and treasures to Chalcedon
in Asia; and as he was always desirous of associating companions to the
hopes and dangers of his fortune, he now bestowed the title of Caesar
on Martinianus, who exercised one of the most important offices of the
empire. [109]

[Footnote 108: Zosimus, l. ii. p. 97, 98. The current always sets out
of the Hellespont; and when it is assisted by a north wind, no vessel
can attempt the passage. A south wind renders the force of the current
almost imperceptible. See Tournefort's Voyage