I learned that New York city was on equal footing with Philadelphia, Baltimore, and New England up until the early 1800's when she 1. began to run regularly scheduled shipping services overseas and around the southern US and 2. opened the Erie Canal. Between the Western and Eastern trade, NYC grew at a really rapid pace.
I also learned that the packet liners had a fairly nice time running East to Liverpool, as they rode the Gulf Stream, but coming back, they had to take a longer route to avoid the Gulf Stream and actually sailed more miles due to tacking (sailing zig-zag upwind). Also, contrary to my assumption, it was more dangerous to sail from NYC down and around to New Orleans because of the hazardous coastal waters and the difficulty in sailing safely into the Gulf of Mexico. Now that I think about it, that does make sense. Just as I learned in the Potomac, it's tricky to sail when you have less room to maneuver!
Interesting stuff :)