The telophone could cost from $20 to $40 per year.
Alexander Graham Bell
Alexander had a few of his family members that have all have worked on elocution and speech. he had a mother and wife which were deaf that influenced his life work. His research of hearing and speech lead him to the experiment with the hearing device, which led to him being awarded the first US Patent for the telephone in 1876.
"The telephone," wrote Alexander Graham Bell in an 1877 prospectus drumming up support for his new invention, "may be briefly described as an electrical contrivance for reproducing in distant places the tones and articulations of a speaker's voice."