When we endeavour to ascertain the probable date of the first invention of the operation in the East, the fog of uncertainty closes down over us, obliterates all trace of our quest, and drives us to fall back on inference. Those who have spent their lives in an Eastern land know the unbending force of tradition, the hereditary character of occupations, and the intense conservatism of Oriental peoples. All these influences are against change of any kind, and greatly retard the spread of new ideas. When we consider an operation like couching, which is well known over the whole of the East, and which meets in the simplest manner an age-long need, felt in every village of a tropical or subtropical country, it is not difficult to believe that the procedure may have been one of the early fruits of advancing civilisation, far away back in Babylon the Great, or even earlier still in the home of the Pyramids, tens of centuries before the dawn of the Christian era. From these attractive speculations we must return to weigh the literature of our subject, of which the foundation was so well and truly laid by the great Celsus. His description of the technique he employed is as follows: “Before the operation the patient must use a spare diet.... After this preparation he must sit in a light place, in a seat facing the light, and the physician must sit opposite the patient on a seat a little higher; an assistant behind taking hold of the patient’s head, and keeping it immovable, for the sight may be lost for ever by a slight motion. Moreover, the eye itself must be rendered more fixed by laying wool upon the other and tying it on. The operation must be performed on the left eye by the right hand, and on the right by the left hand. Then the needle, sharp-pointed, but by no means too slender, is to be applied and must be thrust in, but in a straight direction, through the two coats, in the middle part betwixt the black of the eye and the external angle opposite to the middle of the cataract.... The needle must be turned upon the cataract and gently moved up and down there, and by degrees work the cataract downward below the pupil; when it has passed the pupil, it must be pressed down with a considerable force that it may settle in the inferior part.”