On 10th March of 1876, over a short distance in a laboratory in Boston, history was made when 29-year-old inventor Alexander Graham Bell spoke to his assistant, Thomas Watson, using the telephone he had successfully patented three days earlier. He wrote this entry hours after the experiment, along with a letter to his father in which he declared: “the day is coming when telegraph wires will be laid on to houses just like water and gas — and friends converse with each other without leaving home.” 39 years later, Bell used the telephone to speak with Watson again, but this time over a distance of 3,400 miles.
The Diary Entry
March 10th 1876
The improved instrument shown in Fig.1 was constructed this morning and tried this evening. P is a brass pipe and W the platinum wire M the mouth piece and S the armature of the Receiving Instrument.
Mr Watson was stationed in one room with the Receiving Instrument. He pressed one ear closely against S and closed his other ear with his hand. The Transmitting Instrument was placed in another room and the door of both rooms were closed.
I then shouted into M the following sentence: “Mr. Watson – come here – I want to see you”. To my delight he came and declared that he had heard and understood what I said.
I asked him to repeat the words. He answered “You said ‘Mr. Watson – come here – I want to see you’.” We then changed places and I listened at S while Mr. Watson read a few passages from a book into the mouth piece M. It was certainly the case that articulate sounds proceeded from S. The effect was loud but indistinct and muffled.
If I had read beforehand the passage given by Mr. Watson I should have recognized every word. As it was I could not make out the sense – but an occasional word here and there was quite distinct. I made out “to” and “out” and “further”; and finally the sentence “Mr. Bell do you understand what I say? Do – you – un – der – stand – what – I – say” came quite clearly and intelligibly. No sound was audible when the armature S was removed.
Alexander Graham Bell’s papers are held at the Library of Congress and can be viewed online. These 130,000 items include his correspondence, notebooks, journals, blueprints, and photographs. The book containing this particular entry is here; to see and read the letter written that day by Bell to his father, click here.