"China For America Export Porcelain of the 18th and 19th Centuries" (1980) by 
Herbert, Peter and Nancy Schiffer has a very good introduction to the trade in 
opium and other goods in "Early Chinese-American commerce with porcelain" 
the first chapter, pages 15-20 (it also involved opium trade with Turkey and 
India) The "Experiment" one of the early American ships to sail to China (1786-
1787) built in the Albany, NY area, which sailed with a small crew (ten?) I 
recall, one a free African-American, was successful. I heard at a National 
Maritime Historical Society meeting a number of years ago a replica was 
proposed to be built and sailed back to China to commemorate the historical 
event.