19th century dentistry advertising trade cards. Merrick's Six Cord Thread/Clark's Mile End Thread.
Croll
Theodore
T
Swanson
Ben Z
BZ
D000329:Advertising / Q000266:history*; D049672:History, 19th Century; D011215:Practice Management, Dental / Q000266:history*; D014081:Tooth Extraction / Q000266:history*; D014481:United States