Dr. Paul Israel

He begins to hire more experimenters and more machinists.

And so this is in 1878 that Edison gains this new fame.

And by the end of the year, he's beginning to think about something called electric lighting.

If the phonograph makes him famous, it's the electric light research and development that transforms Menlo Park from what one reporter called an invention factory to really the first industrial research and development laboratory in the United States.

In October of 1878, Edison is describing to the press that he thinks he's solved the problem of creating an electric light system and providing small incandescent indoor lights.

And people connected with the telegraph industry, especially Western Union,

are the first to invest in this, and they set up a company called the Edison Electric Light Company.

And one of the things that happens is that Menlo Park Laboratory grows.

There'd been maybe about a dozen men at Menlo Park by the end of 1878.

He begins to hire new researchers.

and he hires a German scientific instrument glassblower, and they set up a small little building for the glassblower.

There's a carpenter's shop, a big brick machine shop, and the number of experimenters expands.

He's got 25, then 30, and then as they finally reach a point where they have a basic lamp design and a basic generator design,

By the fall of 1879, Edison exhibits his new lamp, and he actually sets up a pilot station in Menlo Park on the model of what he wants to build in New York.

So, yes, this is one of the ironies of Edison's career is how much someone who had some hearing difficulties, it was progressive, it got worse over time, how much he was involved in technologies that involve sound.

So he used to say that he saw his hearing difficulties as an advantage.

So when he was a telegraph operator, it allowed him to focus on the dots and dashes of the telegraph instrument because he wasn't hearing other noise in the room, right?

And then as an inventor of the phonograph, of improved telephone technology, of

In some respects, his hearing was treated as a test instrument.

His ability to hear something meant that it was both articulated and loud enough that it should work in a commercial setting.