That surgery makes the third part of medicine, is both universally known, and has been already observed. This does not indeed discard medicines, and a proper regimen; but yet the principal part is accomplished by the hand. And the effect of this is the most evident of all the parts of medicine. For as fortune contributes a good deal to the cure of distempers, and the same things are often salutary, often fruitless; it may be doubted, whether the recovery be owing to physic, or the constitution. In those diseases also, in which we chiefly make use of medicines, although their success be pretty evident, nevertheless it is plain, that health is both sought for by their means in vain, and often restored without them. As may be observed with regard to the eyes, which after having long suffered from the applications of physicians, sometimes recover of themselves. But in surgery it is manifest that the success, though it may be somewhat promoted by other means, is chiefly to be ascribed to this. Now this branch, though it be the most ancient, yet has been more cultivated by Hippocrates the father of all medicine, than by his predecessors. Afterwards being separated from the other parts, it began to have its peculiar professors, and received considerable improvements in Egypt, as well as elsewhere, principally from Philoxenus, who has treated of this part fully, and with great accuracy, in several volumes. Gorgias also, and Sostratus, the two Herons, and the two Apollonii, and Ammonius Alexandrinus, and many other celebrated men, have each of them made some discoveries. And at Rome too professors of no small note, and particularly of late Tryphon the father, and Euelpistus the son of Phleges, and Meges the most learned of them all, as appears from his writings, by altering some things for the better have made considerable additions to this art. A surgeon ought to be young, or at most but middle aged, to have a strong and steady hand, never subject to tremble, and be no less dexterous with his left than his right hand; to have a quick and clear sight; to be bold, and so far void of pity, that he may have only in view the cure of him, whom he has taken in hand, and not in compassion to cries either make more haste than the case requires, or his cut less than is necessary; but to do all, as if he was not moved by the shrieks of his patient.