The original operation of Dieffenbach, now rarely practised, consisted in making an incision, B B, across the tendon, then, by cutting the areolar tissue exposing the insertion of the tendon, and dividing it freely; after which the sclerotic in the neighbourhood was to be cleaned and any band of fibres divided. There are risks on the one hand of a most unseemly exophthalmos with divergent squint, and on the other of a retraction of the semilunar fold, so that the sub-conjunctival operation is always preferable. OPERATIONS FOR DIVERGENT SQUINT.--This very serious deformity is often the result of the operation for convergent squint, and is associated with a fixed, leering, and prominent eye, and frequently with most annoying double vision. 1. In a simple case of primary divergent strabismus (very rare) it is sufficient simply to divide the external rectus in the manner already described for division of the internal. 2. If secondary to an operation for convergent squint, the indication is to restore the cut internal rectus to a position on the sclerotic a little behind its previous one, as the cause of the divergence is found in a complete detachment of the internal rectus. This is attempted in various ways. (1.) _Jules Guérin_ carefully divided the conjunctiva over it, and sought for the remains of the internal rectus, freeing it from its attachments. He then passed a thread through the sclerotic on the _outer_ side of the globe, and by pulling on it and fixing it across the nose, rotated the eye inwards, in the hope that the remains of the internal rectus would secure a new attachment. (2.) _Graefe's modification_ of this is more certain. Without any minute dissection he merely separated the internal rectus, along with the conjunctiva, and fascia over it, so that it can be pulled forwards, then cut the external rectus, and inverted the eyeball to a sufficient extent by means of a thread passed through the portion of the tendon of the external rectus, which remains attached to the sclerotic. The risk of all these operations, in which both muscles are divided, is protrusion of the eyeball from the removal of muscular tension. (3.) _Solomon's operation for the radical cure of extreme divergent strabismus_,[86] is at first sight a very curious one. Without going into all the details, the steps are as follows:-- _a._ A square-shaped flap, with its attached base at the nasal side, is raised, containing the remains of the inner rectus and its adjacent parts. _b._ A flap similar in shape and size, but different in the position of its attached base, is made on the other side of the cornea. It is made by dividing the external rectus just behind its tendon, and then reflecting forwards the tendon with its conjunctiva.