"This database makes searchable the copyright renewal records received by the US Copyright Office between 1950 and 1992 for books published in the US between 1923 and 1963. Note that the database includes ONLY US Class A (book) renewals."
Call numbers: (check Library Search Catalog for years covered by each call number)
Microfilm: Science Library GRR Microforms S-000325
Paper: Langson Lib Ref: TA 223 A23
Microfiche, U.S. Gov Info: C21.5: (vol./no.)
Browse short summaries of patents. 1872 to present.
Call number paper: Langson Lib. Ref: T223 A25 Begin here. Search this by a word to try to identify the class and subclass into which a patent might fall. Then use these numbers in the Manual of Classification.
With the class and subclass found, then search for all the patents in that class and subclass to all identify patents on that topic. Definitions supply much more information about what is covered within a specific class and subclass. They also provide good cross references to related classes and subclasses.