telephone experiments had been taking place at brown university in providence since the fall of 1876. the professors doing these experiments were peirce, william francis channing and eli whitney blake, jr. by april 1877 they constructed the first portable telephone. this was made of two blocks of wood, one of which had a hole in it for the two inch round converging mouthpiece designed by peirce. the other block of wood supported a horseshoe magnet made of two toy magnets. it had a sheet metal plate on top that was just touching an iron rod with a spool of small gauge insulated wire to pick up voice sounds. the pattern of electrical currents generated by the spool of wire related to a person's voice spoken into the mouthpiece.