August 9: When the side effect becomes the discovery
On August 9, 1892, Thomas Edison received a patent for the two-way telegraph. Tonight's film: Primer (2004).
There’s a date that always stops me when I open the almanac. August 9. Two things happened on this day that belong here: a patent and a black day. Tonight the main act is the patent, because it genuinely fits the film.
On August 9, 1892, Thomas Edison was granted U.S. Patent No. 480,567 for his duplex telegraph system. Two-way, simultaneous communication over a single wire. The curious part is that the patent had been filed on September 1, 1874, so it waited eighteen years for official approval. It was assigned to Western Union. Two operators could send messages at the same time over one wire, one by reversing the battery’s current direction, the other by varying the current’s strength. Before that you needed two separate devices, one to transmit and one to receive. Edison merged them into a single machine.
What always gets me is where these solutions come from. Not from big institutions. Edison worked out of his Menlo Park laboratory. A small team, materials in hand, experimentation and side effects that nobody went looking for. And here comes tonight’s film.
