E. Cobham Brewer 18101897. Dictionary of Phrase and Fable. 1898.
Polycrates (4 syl.),
Tyrant of Samos, was so fortunate in all things that Amasis, King of Egypt, advised him to chequer his pleasures by relinquishing something he greatly prized. Whereupon Polycrts threw into the sea a beautiful seal, the most valuable of his jewels. A few days afterwards a fine fish was sent him as a present, and in its belly was found the jewel. Amasis, alarmed at this good fortune, broke off his alliance, declaring that sooner or later this good fortune would fail; and not long afterwards Polycrates was shamefully put to death by Orts, who had invited him to his court.
Richard [Mutimer], in surveying his guests, had feelings not unlike those which lulled King Polycratês of old.G. Gissing: Demos. chap. xii.