Murdoch has been known to me chiefly as the author of works on philosophy, generally devoted to the rejuvenation of Platonism. They are intelligently written, despite their failure to cause any veering in my own empirical/pragmatic course.
But "The Sea. The Sea" is a novel, written in the form of a journal kept by one Charles Arrowby, apparently a successful theatrical producer who has retired to a village by the sea.
The title, "The Sea, The Sea," was presumably inspired by the ending of Anabasis, Xenophon's book on the adventure of 10,000 Greeks who had to escape from behind enemy lines in Persia. They knew they were safe when they reached the sea -- they were a seafaring people and could get home from there. Hence that glad shout. In ancient Greek, that's Thalatta! Thalatta!
So I suppose the title is meant to convey the idea that Arrowby sees his own retirement as a sort of haven or sanctuary after a rough time inland, amongst the warring theatrical tribes.
There is also a platonism connection in the title, although I'll leave that be for now.
Anyway, early on in this novel, Arrowby is describing his new home for us, and the nearby village of Narrowdean.
"The old form of the name was Nerodene, and a handsome milestone upon the coast road retains this selling." That's a nice detail. Folk etymology has changed many words. People here a name, infer that it must mean something that sounds similar, and soon that similar-sounding word takes over the first one. That's how a large knife of the sort once known as a coutelas became a cutlass. It cuts after all, so that must be what was meant!
Soon, our protagonist is describing the Narrowdean cemetary. "One stone in particular attracts me. It bears a beautiful 'foul anchor' and the simple inscription: Dummy 1879 - 1918. This puzzled me until I realized that 'Dummy' must have been a deaf and dumb sailor who never managed to achieve any other identity."
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That is the sort of insignia known as a "foul anchor." It would certainly tell us of Dummy's occupation. I don't know whether that gravestone will play any part in the rest of the story, but it is at least a fine observation, part of the stage setting.