Thanks Tach... Lakes article mentioned that "Manhattan Beach" was coined or established in 1900... the Library of Congress map I recently found was from 1898 and contained no mention of Manhattan... only Burnside which seemed to be at the terminus of the rail line to the beach... http://www.loc.gov/resource/g3933d.la000075/
Sorry, it's been a bit hard to follow with all the crazy/disappearing comments.
That looks right. I'm not sure anyone knows where the name "Manhattan Beach" came from. If it was built in 1900, it would have been before blacks from the South started going to Manhattan en masse, which kicked off a few years later. Harlem as we think of it didn't exist yet. But like Stephen says, there were other connections, Brooklyn, Murray Hill, etc. The beach was founded by FEC, and a lot of the people involved (including Henry Flagler) were from New York.