Cannonmn,
I found the article about the French guns coming from Richmond interesting, it seems that there is a 1860's news paper piece somewhere on
the web that mentions the French cannon that were given as gifts to the city by the french, and their possible use in the war. So these may have been
gifts from France and not left by the French at Yorktown.........
Thanks for posting the links there are far more cannon there than I thought, and some fairly early cannon too, at least on from the Sun King.