OPHTHALMIC OINTMENTS have been, and are, prescribed and used by ocular surgeons throughout the civilized world. By far the most commonly used by the family physician is yellow mercuric oxide. The American lay public long used this ointment as a household remedy for external diseases of the eye; it is now to be replaced by sulfathiazole ointment. In the experience of one of us (L. L.), the same collapsible tube containing an ointment of mercury bichloride U.S.P., boric acid ointment U.S.P. or ammoniated mercury ointment U.S.P has been used in the treatment of numerous patients in office practice, with a thought to economy, until the last wormy drip has been expressed. At the Wills Hospital, it was our experience for years to use an ointment containing mercury bichloride (1:3,000) after all cataract operations, merely because we had seen our predecessors use the same technic. Not more than seven years ago,