The first long-distance call came with receipts

When the telephone finally traveled a real distance, nobody believed it. So the inventor kept a transcript.

On October 9, 1876, Alexander Graham Bell sat in the office of the Walworth Manufacturing Company on Kilby Street in Boston. His assistant, Thomas A. Watson, sat about two miles away in Cambridgeport, at the far end of a borrowed telegraph wire strung outdoors.

The famous "Mr. Watson, come here" of the previous March had carried only between rooms of the same building. This was the first two-way conversation to cross open ground.

The two men talked for hours, sometimes in ordinary voices, sometimes in whispers. Each wrote down what he said and what he heard. Afterward, according to the Smithsonian Institution, the two records were printed side by side so readers could check one against the other — proof that no confederate was hiding in the next room.

The transcripts matched almost word for word. A historical marker still hangs at the Cambridge end, on the corner of the old Davenport car factory.