By David Freeman Hawke; Harper & Row; 308 pages.

Before America could be settled, a lot of trees had to be cleared. The clumsy axes the early pioneers brought from Europe were plainly inadequate. A new ax evolved, an efficient, precisely balanced tool that, in the hands of a skilled woodsman, could fell three times as many trees in the same amount of time. From the beginning, according to David Freeman Hawke, new technology has played an integral role in the making of America.

As in his previous book Everyday Life in Early America , Hawke draws upon the work of other scholars, this time historians of technology, and reweaves their often dauntingly academic writings into a book accessible to non-historians. He has assembled a new cast of founding fathers, “men with dirty fingernails,” including John Fitch, Cyrus McCormick, and Samuel Slater. These men had new ideas. They combined mechanical aptitude with visionary genius, inventive insight, or just plain doggedness, to transform a nation of pioneers and farmers into a mighty industrial power.

Such a man was Oliver Evans, the son of a Delaware farmer. In 1777 he set out to build a machine that would make cards—wire-toothed combs used to unsnarl wool and cotton fibers prior to spinning. Evans’s father told him it would never work. It never did, but his automated gristmill fared better, reducing the work of eight men to that of two, though it took decades for the machine to catch on.

Near the end of the century Evans submitted a sensible plan for Philadelphia’s new municipal water system. He lost to Benjamin Latrobe, in part because Latrobe had nicer drawings. Evans bitterly recalled the lavish illustrations of the neoclassical pumping house “with its Doric columns and pediments . . . its center dome-shaped building covering the reservoir, with the novel expedient of stack and chimney, terminating on the apex of the dome, vomiting its wreath of black smoke.” Latrobe’s seventy-five-hundred-gallon reservoir turned out to be far too small to meet the needs of the city. Within fifteen years Philadelphia installed a new waterworks quite similar to the one Evans had envisioned.

Evans, though a mechanical genius, failed as an entrepreneur. He was a “dirty-fingernail” man, and selling new technologies often required the skills of a different breed, the “song-and-dance” man. People like Eli Whitney had big schemes and knew how to sell an idea. His claim that his guns had interchangeable parts was a scam, but he made the idea popular, and by the 1820s rifles with fully interchangeable parts were being machined by John Hall at Harpers Ferry.

Hawke goes on to examine the contributions of men like the sewing-machine innovator Isaac Singer, Eli Terry, who democratized timekeeping with his mass-produced wooden clocks, and Samuel Morse, an artist turned mediocre scientist and technician who nevertheless managed to invent telegraphy and open the