Henry Stevens hadn't seen a cow in years. Illness had taken his sight in middle life. But every morning, he walked through his barn at Brookside Farm, running weathered fingers along toplines and udders, making breeding decisions that confounded rivals with perfect vision. His sons learned to trust their blind father's hands more than their own eyes. In 1912, a cow from his program became the first animal of any breed to produce 1,000 pounds of butterfat in a year. The blind man had seen further than anyone.

This is the story of four visionaries who, in just 30 years, transformed an obscure Dutch dairy cow into the dominant force in global milk production. A Boston merchant who ordered replacement cattle the very day the government destroyed his herd. A reformer's grandson who walked his first Holsteins through October snow. Nurserymen who  ...