Seventh among them must be reckoned Basilides, who led the renowned Potamiaena to execution. The praises of this woman are even today loudly sung by her own people. Endless the struggle that in defence of her chastity and virginity, which were beyond reproach, she maintained against lovers, for her beauty of body as of mind was in full flower. Endless her sufferings, till after tortures too horrible to describe she and her mother Marcella found fulfilment in fire. It is said that the judge, Aquila, subjected her whole body to dreadful agonies, and finally threatened to hand her over to the gladiators for bodily insult. She reflected for a moment, and when asked what she intended to do, gave an answer which offended their religious prejudices. She had hardly spoken when she heard sentence pronounced, and Basilides, a member of the armed forces, seized her arm and led her away to execution. As the crowd tried to plague her and insult her with obscene jests, Basilides thrust them back and rove them away, showing the utmost pity and kindness towards her. Potamiaena accepted his sympathy for her and gave him encouragement: when she had gone away she would ask her Lord for him, and it would not be long before she repaid him for all he had done for her. This said, she faced her end with noble courageslowly, drop by drop, boiling pitch was poured over different parts of her body, from her toes to the crown of her head. Such was the battle won by this splendid girl.
Not long afterwards Basilides was for some reason asked by his fellow-soldiers to take an oath, but he insisted that he was unable to swear in any circumstances, as he was a Christian and made no secret of the fact. At first they thought he was joking, but when he stuck doggedly to his assertion he was brought before the magistrate, who, as he made no attempt to hide his convictions, committed him to prison. When his brothers in God visited him and asked the reason for this amazing impulse and determination, he is said to have declared that three days after her martyrdom Potamiaena stood before him in the night, put a wreath about his head, and said that she had prayed for him to the Lord, had obtained her request, and before long would place him by her side. At this the brethren bestowed in him the seal of the Lord, and the next day nobly witnessing for his Lord, he was beheaded. The records state that at this period many other citizens of Alexandria accepted the teaching of Christ in a body, as Potamiaena appeared to them in dreams and called them.
From Eusebius: The History of the Church pp. 184,185