Read the text about Alexander Graham Bell and do the tasks

Read the text about Alexander Graham Bell and do the tasks

  Alexander Graham Bell  is widely known  as inventor of the first telephone. He was born on March 3rd, 1847 in Edinburgh, Scotland. When he was 23, Bell emigrated to Canada with his parents and the next year moved to the United States to teach deaf-mute children. With his  colleague Thomas Watson , Bell worked very hard on the experimentation to invent devices such as the  harmonic telegraph ( used to send multiple messages over a  single wire) and phonautograph ( used to draw the shape of the sound  waves). The first telephone communication was said to have happened between Bell  and Watson in 1876 while Bell was at one end of the line, and Watson worked on the telephone in other room. The first transmitted words were, ‘ Mr Watson, come here . I want  to see you’

 

Answer the questions

1.What is Bell ‘s ‘harmonic telegraph’ ?

2.What is Bell ‘s ‘phonautograph’

3.When did the first communication over happened and how did it happen?