[PT031AAB], Patent Caveat, Thomas Alva Edison, October 15th, 1888
date of oath of Sept. 21 phonograph caveat
Chemicals, chemical products, and chemical processes
Cylinder record and duplicating technology
[PT031AAB-F] Patent Series -- Caveat Files
https://edisondigital.rutgers.edu/document/PT031AAB
Thomas A. Edison Papers, School of Arts and Sciences, Rutgers University
Archive.org Viewer, Microfilm Series Reel 113