One reason for the success of the iPhone is its size. Steve Jobs was a student of ergonomics and understood that a smart phone needed to be large enough to have legible graphics but small enough to fit in the hand. Apple apparently hit that “sweet spot” in designing it.

Clive Thompson, writing in the Smithsonian, explains how a similar phenomenon occurred seventy-five years ago with another American innovator. Robert Fair de Graff realized he could change the way people read books, by making them smaller. Paperback books changed America’s reading habits. To understand this, we have to look at the world before paperback books.

Good fiction and nonfiction books were not that easy to obtain. First, there were only about 500 bookstores in America, mostly clustered in the big cities. Second, books back then were expensive. A hardcover book cost $2.50. That is equivalent to paying $40 for a book today.

De Graff changed everything when he got the backing of Simon & Schuster to launch Pocket Books. These small paperback books not only easily fit in the hand but they were much less expensive. They sold for a mere 25 cents.

He also worked on distribution. Pocket Books sold in grocery stores, drugstores, and airport terminals. We take for granted that we can buy books in these venues today, but that was revolutionary back in his day. This publishing revolution was a great success. Everyone was reading paperback books. Within two years, Simon & Schuster sold 17 million.

Historian Kenneth C. Davis in his book, Two-Bit Culture, explained that the publisher “couldn’t keep up with the demand. They tapped into a huge reservoir of Americans who nobody realized wanted to read.”

Today, of course, Americans read not only printed books but e-books in a variety of formats. So as we are watching this new electronic revolution in publishing and reading, we should remember the earlier revolution when paperback books encouraged more people to read.