Corrected entry: In the scene where Doc is at the saloon, after Clara doesn't believe him, he orders a drink. The bartender then says "I don't know about that, remember what happened on the Fourth of July?" Doc arrived in 1885 on September 1st. He wasn't there on the Fourth of July.
WhoaMyMaya
27th Aug 2011
Correction: Doc got zapped back to Jan 1st, 1885. In his letter at the beginning of BTTF 3 he mentions that he had been living for 8 months in 1885. So it is possible that he was there on the Fourth of July.