Q. Where can I find a list of the original members of the PHS?
See our digitized copy of James Boyd's
A history of the Pennsylvania Horticultural Society, 1827-1927
p. 368 for the list of the original 80 (not 53) original members.
Your number 53 may have come from Boyd p. 41 which states 53 members had paid their annual dues by July 1828, and I see that our website says 53 so I'll alert the marketing department to correct that little error.