The Druids of the British Isles kept most of their wisdom written on easily burnt wooden tablets. After they were defeated by the Romans, much of their thinking was wiped out. Now Making of a Druid grants insights into the corpus of knowledge Druids would have known, a pool of knowledge that took 15-20 years to acquire. But you can read it all in a couple of hours.  Author and Celtic scholar Christian J. Guyonvarc'h tells the story that appeal both to modern druids and Celtic aficionados.(This book may contain a sharpie mark on the top or bottom edge and may show mild signs of shelfwear.)