Today, we create new technologies to take us west. The University of Houston's College of Engineering presents this series about the machines that make our civilization run, and the people whose ingenuity created them.

The axe, the steamboat, and the railroad tell three stories of technological change. All three began in Europe. And George Basalla tells how each became unique American means for speeding our westward expansion.

First, our colonists used European axes. Europeans had cleared their lands long ago. They would still fell an occasional tree. But European axes were designed to shape wood, not to clear land. We needed far more bite with each axe stroke.

Around 1715, American blacksmiths began counter-weighting the back of axe heads. That improved the balance and increased the cut on each stroke. Ever since, American axe heads have been made with a blade on one side of the handle and a flat weight on the other. We suddenly tripled the speed of felling trees.

The steamboat was also a European invention. We built our first steamboats on the Eastern seaboard. They, like the early European ones, had the same shape as sailing vessels.

Almost immediately we began making riverboats in the inland river port of Pittsburgh. As we moved away from the cosmopolitan seacoast to America's interior river system, we began thinking like river people. Almost immediately, we turned steamboats into buoyant flat-bottomed water lilies -- shallow-draft boats with nothing left to protect them against ocean waves.

Then railroads joined the westward movement. English railroads had been built in straight lines. If there was a hill, the English dug a tunnel. If there was a stream, they built a bridge.

Our landscape was too grand for that. American mountains were a far cry from English hills. Our distances were too great for simple straight lines. If our railroads hadn't followed the curve of the land, we never could have afforded them.

So we reinvented the locomotive to negotiate less friendly track. We put sets of small idler wheels on the front of our locomotives. They distributed the weight and gave greater stability on curves. We shifted our attention from the quality of the roadbed to the quality of the locomotive. Then we simply flung track across our immense land.

Today, we've made our westward trek. Our priorities are different. Now the environmental assault of the felling axe frightens us. We remember how many people died in riverboat accidents. We want to turn attention back to the quality and safety of railroad beds. We're through expanding into a vacuum.

But felling axes, river gamblers, and Casey Jones are deeply woven into our sense of self. They form our once-wild child whom we now leave behind -- as we prepare to survive the 21st century.

I'm John Lienhard, at the University of Houston, where we're interested in the way inventive minds work.

(Theme music)

Basalla, G., The Evolution of Technology. New York: Cambridge University Press, 1988, Chapter III. (I'm grateful to Thomas McConn for drawing this rich source to my attention.)