This morning we had a fair breeze for some hours, and then a calm that lasted all day. In the afternoon I leaped overboard and swam round the ship to wash myself. Saw several porpoises this day. (Benjamin Franklin, Friday, August 3, Journal of a Voyage, 1726)These frescoed dolphins, from the Irakion Museum, seem to be swimming both above and below the sea floor, with sea urchins, like stalactites and stalagmites, on either end. Maybe this led to speculation that the fresco really belongs on the floor. Seen a bit more up close, we see that the artist has put wavy lines along their flanks, no doubt to simulate, or to recall, their rapid motion through the waves. They also seem very purposeful, these, er, porpoises.