Hildegarde was born of noble parents at Boeckelheim, in the county of Sponheim, about the end of the eleventh century (probably 1098). In her eighth year she went for her education to the Benedictine cloister of Disibodenberg. When her education was finished, she entered the cloister, of which, at the age of about fifty, she became abbess. Her writings, reputation for sanctity, and her wise saintly rule attracted so many new members to the community that the convent became overcrowded. Accordingly, with eighteen of her nuns, Hildegarde withdrew to a new convent at Rupertsberg, which English and American travellers will remember because it is not far from Bingen on the Rhine. Here she came to be a centre of attraction for most of the world of her time. She was in active correspondence with nearly every important man of her generation. She was an intimate friend of Bernard of Clairvaux, who was himself, perhaps, the most influential man in Europe in this century. She was in correspondence with four Popes, and with the Emperors Conrad and Frederick I, and with many distinguished archbishops, abbots, and abbesses, and teachers and teaching bodies of various kinds. These correspondences were usually begun by her correspondents, who consulted her because her advice in difficult problems was considered so valuable. In spite of all this time-taking correspondence, she found leisure to write a series of books, most of them on mystical subjects, but two of them on medical subjects. The first is called "Liber Simplicis Medicinae," and the second "Liber Compositae Medicinae." These books were written in order to provide information mainly for the nuns who had charge of the infirmaries of the monasteries of the Benedictines. Almost constantly someone in the large communities, which always contained aged religious, was ailing, and then, besides, there were other calls on the time and the skill of the sister infirmarians. There were no hotels at that time, and no hospitals, except in the large cities. There were always guest houses in connection with monasteries and convents, in which travellers were permitted to pass the night, and given what they needed to eat. There are many people who have had experiences of monastic hospitality even in our own time. Sometimes travellers fell ill. Not infrequently the reason for travelling was to find health in some distant and fabulously health-giving resort, or at the hands of some wonder-working physician. Such high hopes are nearly always set at a distance. This of itself must have given not a little additional need for knowledge of medicine to the infirmarians of convents and monasteries. There were around many of the monasteries, moreover, large estates; often they had been cleared and made valuable by the work of preceding generations of monks, and on these estates peasants came to live. Workingmen and workingwomen from neighboring districts came to