Scion of the Pittsburgh oil and banking family, William Larimer Mellon, Jr., was married, the father of three, and a successful rancher in Arizona when, at thirty-seven, he read a Life magazine article about Albert Schweitzer's "reverence for life" that guided his mission hospital in a remote area of Gabon, Africa. Mellon immediately wrote to the famous humanitarian in Lambarene, expressing admiration of Schweitzer's life of service and the wish to engage in similar work with his wife, Gwendolyn. Schweitzer's reply in March 1948 was a lengthy letter of realistic encouragement. In time, Mellon received his medical degree from Tulane University and later established a well-equipped hospital in one of the poorest regions of Haiti, where, with his wife, he spent the rest of his life working as a physician and a community development engineer. The hospital continues to thrive. Brothers in Spirit brings together sixty-five of the letters written between 1947 and Schweitzer's death in 1965. Presented here in both English and the original French, they eloquently tell the story of a comfortable life abandoned for the goal of serving humanity.