电话发明者贝尔英文介绍.pptVIP

Alexander Graham Bell;*Born: March 3, 1847 *Parents: Alexander Melville Bell and Elisa Grace Symonds *Siblings: 2 brothers, Melville and Edward;Alexander Graham Bell grew up in Edinburgh, Scotland with his family.;Learning From the Family;Hello Grandpa!; Bell read books in the library about Herman von Helmholtz, a German scientist who experimented with electrical vibrations to make vowel sounds. ;Early Life ;Tuberculosis-1870; After Graham was safe from catching the disease, his job led him to be a physiology professor at Boston University in the United States.; While Bell was in Massachusetts, he invented the harmonic telegraph, an instrument that makes it possible to send multiple telegraphs on one line.; On March 7, 1876, Bell recieved his patent for the telephone.;“Mr.Watson, come here, I want you.”; The experiment they were working with had reeds that were thin and steel. One of the reeds was stuck so Watson plucked it to try to fix it.; When he did, Graham heard the vibration clearly through the newly invented ‘telephone’. ; ;The Hook Switch; The speaker picks up the sounds waves from the other line, and sends them through the network to your ear drums. The sounds vibrate in your ear, and you then have sound.;The Microphone;A More Modernized Telephone;The Duplex Coil;The Ringer;Keypad;The Telephone;The Telephone Today;A Sad day in History;Bibliography;About Me!;