Conversation so far:
What were Alexander Graham Bell's later inventions?
Bell worked extensively in medical research and invented techniques for teaching speech to the deaf.
What ideas did he have regarding teaching speech to the deaf?
CANNOTANSWER.
Were there any other inventions?
The range of Bell's inventive genius is represented only in part by the 18 patents granted in his name alone and the 12 he shared with his collaborators.
These included.
What do he hold these patents for?
included 14 for the telephone and telegraph, four for the photophone, one for the phonograph, five for aerial vehicles, four for "hydroairplanes", and two for selenium cells.
Is there anything else interesting about Bell's later inventions?
and included a metal jacket to assist in breathing, the audiometer to detect minor hearing problems, a device to locate icebergs, investigations on.

Question: How did his later inventions compare to the invention of the telephone?
Self-contained rewrite: How did Alexander Graham Bell's later inventions compare to the invention of the telephone?