The samurai chemist Jokichi Takamine (1854-1922) crystallized adrenalin, the first hormone to be isolated in the twentieth century, from the adrenal medulla, in the summer of 1900. This paper reviews Takamine's route to the discovery of adrenalin and presents historical photographs and documents collected in Kanazawa, Japan, where he grew up, and the United States, where he made his major discoveries.