[Arthur Biedl and the beginnings of modern endocrinology. On the 125th birthday of the Austrian pathophysiologist].

Modern endocrinology began to develop at the end of the nineteenth century in four stages: the recognition and localization of endocrine glands, the experimental proof of internal secretion by means of destruction and substitution in animals, their isolation and lastly the synthesis of pure hormones. Arthur Biedl (1869-1933), an assistant of Salomon Stricker (1834-1898), was essentially involved in the first two stages of this research process. This paper presents his work from 1895 to 1914.