Dr. Paul Israel

One of the things that Edison learned very early in his career as a telegraph inventor, the fellow who was the president of the Golden Stock Telegraph Company, which was the

took Edison to his patent attorney.

And the patent attorney had Edison write down all the things he was working on at the time.

And the last page of the book has this very interesting notation that he clearly was told by the patent attorney, "'Hereafter, I will keep a complete record of all inventions.'"

In the U.S.

system, it's not first to file, which is what it was in many European countries, such as England.

In the U.S., it was first to invent.

And so part of that was proving that you invented something before a competitor did.

And one way to do that was to keep a very good record of your experimental work.

And so Edison learned this lesson.

And that's why there are about 4,000 notebooks, not just Edison's, but everybody that worked for him kept notebooks.

And we don't even have all the notebooks that were kept by all the other researchers.

Some of them walked off with theirs.

So this is why we have a great record of the experimental work that went on in Newark, in Menlo Park.

and then at West Orange.

Edison understood the value of these records, but he also learned, and in part this was because he was in the telegraph industry where people like the head of Golden Stock and then later the president of Western Union began to see controlling the technology through patents was a way to prevent competitors from entering into the industry, right?

Didn't always work, but it gave those companies an advantage.

And this is something Edison learned.

And so one of the things he did was he patented variations on an invention, realizing that he could use that to protect his patent position and that of his companies.

Right.