With many thanks to James M. Pfundstein on the Classics List, here is
the material on Caligula walking on the sea that I mentioned as possible
background for Mark's story of Jesus walking on the sea.
Caligula's Bridge over part of the Bay of Naples From Baiae to
Puteoli), and his motive for making it, is in Suetonius' biography of
him, cap. 19. The text can be found on-line at the Latin Library.
The same story is told with more detail at Cassius Dio 59.171-11. In
the last section Caligula is described as having said that Poseidon
(or Neptune) was afraid of him and his hangers-on. I don't have the
Greek handy, but and English translation of the whole history was put
up by the indefatigable Bill Thayer at his Lacus Curtius site.
Caligula's battle with the ocean is a little later in the same book--
Jeffrey B. Gibson, D.Phil. (Oxon.)
1500 W. Pratt Blvd. #1
Chicago, IL 60626