A little piece of history has been placed up for auction recently. It is a letter from Alexander Graham Bell to his father, with a drawing of his plans for the telephone.
Bell writes in the letter, postmarked from Washington DC, on December 30, to his parents that he is ‘quite troubled by your account of the lightning accident at Tutelo Heights. The accident shows that the earth terminals of your telephone line are defective for the current found a shorter path to the ground through two of your poles than by the proper path’.
And he goes on to draw a remarkable diagram – two telephones – showing the correct mechanical assemblage to ensure proper function and, above all, safety.