We were suddenly getting big, with burgeoning capabilities on all sides, but very clumsy, knew we were on some kind of ride, and things changing fast, but with very little idea of what was going on.

The evolution was always to greater scale and speed. Other countries did that here and there - GB in textiles, Germany in steel - but we went in that direction almost across the board.

I would speculate that a critical mass of the population has to internalize a middle class outlook first. International aid experience has demonstrated many times that just building railroads doesn't get you there. You need people ready to sue them.

After I finished the Tycoons - on post-Civil War development - I realized how much I didn't know about the first half of the century, even though there had obviously been an enormous amount of development, so I read about and thought about that for a couple of years before I decided I was ready for a book.

It's clear that North took some original steps in that direction, but Hall probably had the most complete approach and should get the most credit. But for Hall, unfortunately, the data are all impressionistic - what people said. None of his machinery survived. His patents were all lost in the Patent Office fire.

We were suddenly getting big, with burgeoning capabilities on all sides, but very clumsy, knew we were on some kind of ride, and things changing fast, but with very little idea of what was going on.

n truth, we don't know a whole lot of what Simeon North did. He did manage to match John Hall's ability to make interchangeable parts, but it's not clear how much of that came from Hall and how much was original with North.