of chart form

Full Title

Manually- or mechanically-operated teaching appliances working with questions and answers > of the type wherein the student is expected to construct an answer to the question which is presented or wherein the machine gives an answer to the question presented by the student > of chart form

Classification Context

Section:

PHYSICS

Class:

EDUCATING; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS

Subclass:

EDUCATIONAL OR DEMONSTRATION APPLIANCES; APPLIANCES FOR TEACHING, OR COMMUNICATING WITH, THE BLIND, DEAF OR MUTE; MODELS; PLANETARIA; GLOBES; MAPS; DIAGRAMS