http://www.drphysick.com/drphysicksoda.html
What a surprise this bit of history was. Who knew that Philly was the
home of soda pop?
This came to me as a recommendation from Georgia Guthrie at The Hacktory
See some other of Georgia's recommendations here:
http://www.wikidelphia.org/index.php?title=The_Hacktory
Stan