by Leonard Mosley Atheneum 32 photographs, 448 pages, $15.00

It is hard to read the history of America since 1800 without running into du Ponts. The first patriarch helped Jefferson negotiate the Louisiana Purchase; generations later, du Ponts designed the first secret atomic plants in World War II. The family business has provided gunpowder of increasing sophistication for all of America’s wars from 1812 on, and Du Pont chemists have produced dozens of items as indispensable in our lives as cellophane and nylon.

That we know less about individual du Ponts than about Rockefellers or Vanderbilts, Mosley says in this highly entertaining history of the dynasty, is because self-appointed family archivists and the company’s “tight-lipped public relations men” have for years sanitized the record. Only recently have scholars been permitted to poke around in family papers.

The first Pierre Samuel du Pont advocated marriage between cousins to ensure “honesty of soul and purity of blood.” Several generations later, the reigning patriarch was grumbling that “the thinning” of that pure blood by inbreeding was producing freaks. But the intermarrying cousins, most of them clustered around the original family holdings on the Brandywine River, went right on producing scores of little Pierre Samuels, Alfreds, and !renées with the typical long du Pont noses, and the family disposition toward tuberculosis. By the 1920’s, the close Delaware clan was the richest family in America.

Mosley’s lively chronicle weaves together a sweeping business history—well larded with corporate dirty tricks—and the personal stories of dozens of du Ponts, the honorable ones, the stuffy ones, and the outrageous ones. The family may regret that they ever let the scholars in.