The author has long been interested in how plant derived substances can prove beneficial to Medicine. Writings on papyrus from the earliest times have described the use of willow bark for soothing inflamed wounds. Major contributions by the Reverend Edward Stone of Chipping Norton, and Dr. Thomas Maclagan of Dundee are covered, along with the unique discovery by Professor John Vane and his team, of the fundamental effect of aspirin on prostaglandin synthesis. The book includes fascinating memorabilia on the early days of aspirin, kindly donated from the Bayer archive.In his first book on the foxglove, the author described how Nature's gift of digitalis came to become accepted worldwide as a valuable treatment for heart failure. Now, he has explored the bark of the willow, from which by chemical modification, aspirin was obtained. But whereas up to now, digitalis (in its current form, digoxin), only has a place in the treatment of heart disease, aspirin - the world's most ubiquitous pain killer, has in the last half-century, been shown also to prevent heart attacks and strokes. And in addition it may soon come into use in cancer prevention.