4. M. OCTAVIUS HERENNIUS, was originally a flute-player, but afterwards engaged in trade, and throve so well that he dedicated to Hercules a tenth of his gains. Once, while sailing with his wares, Herennius was attacked by pirates, but he beat them off valiantly, and saved his liberty and cargo. Then Hercules showed Herennius in a dream that it was he who had given him strength in his need. So, when he came back to Rome, Herennius besought the senate for a piece of ground, whereon he built a chapel to Hercules, and placed in it an image of the god, and wrote underneath the image "Herculi Victori," in token of his deliverance from the pirates.
The chapel stood near the Porta Trigemina, at the foot of the Aventine.
The story of its foundation is probably a temple legend. (Masurius Sabinus, Memorial.
ii. apud Macrob. Sat.
3.6; Serv. ad Aen. 8.363
The latter, indeed, calls the pious merchant M. Octavius Eserninus, but his version of the story is substantially the same with that in Macrobius.