Galen (130-200 A. D.) was a most voluminous writer, much of whose work remains and teems with matter of interest to us. Much information about instruments is to be gained from even his purely anatomical writings. The most accessible edition is that of Kühn (20 vols., Leipzig, 1821), but it is slipshod in the text, and even more so in the translation, which is in Latin. Oribasius (325 A. D.) wrote an encyclopaedia of medicine, which is called Συναγωγαὶ Ἰατρικαί--Collecta Medicinalia, in seventy books, only about one third of which remain. This is the most interesting of his works from our point of view, but he has left also a synopsis of the encyclopaedia called Σύνοψις, and a sort of first aid manual called Εὐπόριστα. I have used the edition of Daremberg and Bussemaker (1851-76). Soranus of Ephesus has left us a most valuable treatise on obstetrics and gynaecology, which, though written only for midwives, contains many interesting references to instruments such as the speculum, uterine sound, cephalotribe, decapitator, and embryo hook. He lived in the reign of Trajan. Some of the chapters, of which the Greek is lost, have been preserved to us by his abbreviator Moschion. I have used the edition of Rose published at Leipzig in 1882. Moschion (fifth century) translated into Latin the gynaecological and obstetrical part of the works of Soranus for the benefit of midwives who could not speak Greek. This version is now lost, but we have a translation of it into Greek, made after the fall of the Western Empire and the development of the Greek-speaking Empire at Constantinople in the sixth century. There is an Edition of this by Gesner (Basle, 1566). Finally, this Greek version of Moschion was translated back into barbarous Latin at some early date, Barbour thinks by some member of the Schola Salernitana. This was published at Venice by Aldus in the sixteenth century, and Rose has prefaced his edition of Soranus with it. This work of Moschion is only of interest to us from the fact that he preserves to us the substance of some chapters of which the original in Soranus is wanting. Caelius Aurelianus Siccensis, an African of the fourth or fifth century, translated the works of Soranus, both those on gynaecology and those on general diseases, and he preserves some of Soranus which we would not otherwise possess; but he writes in a barbarous Latin which, like the Latin of some other African writers on medical subjects, is calculated to cause great pain to any one not familiar with this particular style.