Hylas and the Nymphs by John William Waterhouse (1896). Source: Wikipedia
Hylas
While they prepared the evening meal, Heracles went in search of a tree which would serve to make him a new oar. He uprooted an enormous fir, but when he dragged it back for trimming beside the camp fire, found that his squire Hylas had set out, an hour or two previously to fetch water from the near-by pool of Pegae, and not yet returned; Polyphemus was away, searching for him. (Hylas, Amycus and Phineus, The Greek Myths by Robert Graves, pp 589-594).
Heracles had broken his oar due to a contest he had initiated amongst The Argo’s crew to see who could row the longest, in order to speed progress with the voyage. As the Argonauts wearied, Heracles’ own oar snapped and the ship therefore put in at the mouth of the River Chius in Mysia. The disappearance of Hylas distressed Heracles mightily, because he loved the young man, whom he had spared after killing his father, King Theiodamas of the Dryopians. Heracles eventually met Polyphemus who had been unable to find hide nor hair of Hylas, except his water pitcher, abandoned at the edge of the pool of Pegae.
Unknown to the two of them, the young and beautiful Hylas had been seduced by the water-nymph Dryope and her sister-nymphs at Pegae and they had enticed the love-struck young man to come and live with them in their underwater grotto. Heracles did all he could to locate Hylas, including forcing scores of Mysians to join the search, but to no avail. He never saw Hylas again.
Eventually Jason wearied waiting for the return of Heracles, Polyphemus and Hylas and ordered the voyage to resume, although many of the Argonauts were unhappy at the decision.
Graves suggests that the true fate of Hylas was that of many a Year King: to be dismembered and eaten by wild women, who then purified themselves in a spring and announced that the young man had unaccountably vanished.
