I just want to thank Matt Seybold for his essay /EVEN IF HE WEREN’T MY 
FRIEND: FREDERICK DOUGLASS & MARK TWAIN, 
<https://marktwainstudies.com/freddouglassmarktwain/>/ He offers an 
excellent summary of the history of the Douglas-Langdon relationship and 
for my purpose, a strong argument for Twain's presence at the Douglas 
speech  on that date.

-- 
/Unaffiliated Geographer and Twain aficionado/