Which preposition to use with bucentaur

to Occurrences 1%

When she hove in sight, Perry halted, resumed his stately demeanor, and em-barked as if he were a Doge entering a Bucentaur to wed a Sea.

within Occurrences 1%

Any of those who had been engaged in the previous trial were admitted to this; and all desirous of taking part in the new struggle were commanded to come beneath the stern of the Bucentaur within a prescribed number of minutes, that note might be had of their wishes.

Which preposition to use with  bucentaur