About the Manhattan Bridge 

See, Acps110, I read the history site on the W train page. It says When all four tracks on the Manhattan Bridge were restored on February 22, 2004, the W was changed to its final service pattern as a weekday local between Whitehall Street – South Ferry and Queens. This means the W was local and the N was express. That's when the Manhattan Bridge's north tracks reopen for the B and D trains. Read more about the service history of the B, D, N, Q and W train pages so you can get a better understand you meanie. D: