This is all conjecture, but very reasonable conjecture; what we know for a fact is that he saw the white gum drawn from the lentiscus shrubs in Chio at the time of their flowering; that fragrant memory is preserved long afterwards in his own writings, evoked by some incident in the newly-discovered islands of the West.

There are vague rumours and stories of his having been engaged in various expeditions -- among them one fitted out in Genoa by John of Anjou to recover the kingdom of Naples for King Rene of Provence; but there is no reason to believe these rumours: good reason to disbelieve them, rather.
The lives that the sea absorbs are passed in a great variety of adventure and experience, but so far as the world is concerned they are passed in a profound obscurity; and we need not wonder that of all the mariners who used those seas, and passed up and down, and held their course by the stars, and reefed their sails before the sudden squalls that came down from the mountains, and shook them out again in the calm sunshine that followed, there is no record of the one among their number who was afterwards to reef and steer and hold his course to such mighty purpose.
For this period, then, we must leave him to the sea, and to the vast anonymity of sea life..