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Alexander Graham Bell is also credited with the invention of the [[hydrofoil]] boat, the [[metal detector]], and a predecessor to the [[iron lung]].  

Alexander Graham Bell is also credited with the invention of the [[hydrofoil]] boat, the [[metal detector]], and a predecessor to the [[iron lung]].  

Bell obtained 14 patents 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".

Bell obtained 14 patents for the "telephone" and "telegraph", 4 for the "photophone", 1 for the "phonograph", 5 for the "aerial vehicles", 4 for the "hydroairplanes" and 2 for the "selenium cells".

== References ==

== References ==