Neither can much or any benefit be expected to follow attempts to force obstruction in the lachrymal passages, by the weight of a column of mercury. A plan of dilating and rectifying the nasal duct by styles introduced through the puncta has been proposed, but scarcely deserves to be mentioned as a means of cure. When suppuration is threatened, with increase of the swelling, inability of the patient to empty the sac by pressure, redness of the integuments, &c., an early opening should be made into the tumour, in order to prevent further and more serious mischief. A small opening into the sac cannot be productive of so much injury as forcible dilatation of the canaliculi, followed by and causing ulceration. The point of a straight narrow bistoury is to be entered into the sac, and carried on into the nasal duct, the knife being pushed downwards, backwards, and a little inwards, in the direction of that passage. The point to be punctured can always be readily ascertained by feeling for the firm ligament which attaches the orbicularis palpebrarum to the nasal process of the superior maxillary bone, as the upper orifice of the ductus ad narem is situated immediately below this tendon; by introducing the knife below the ligament, and within the sharp edge of the orbit, and then carrying it forward in the direction already mentioned, the surgeon cannot fail to enter the nasal duct. The knife should be followed by a probe, and ought not to be entirely withdrawn till the probe is fairly lodged in the duct, otherwise the surgeon will experience much difficulty in the after proceedings. If the knife be not pushed into the duct, a blunt instrument can scarcely be introduced afterwards. Some force is required, but is not hurtful, provided it be made in the proper direction, so as to remove the obstruction in the duct without injuring the bones and other parts in the neighbourhood. After the operation, some drops of blood should escape from the corresponding nostril, showing that it has fairly entered this passage; or the patient being made to expire forcibly, the nostrils being at the same time compressed with the fingers, air, blood, and mucus are forced upwards through the opening made. Many and various modes have been pursued with a view of securing a pervious state of the nasal duct. Instruments of different kinds have been introduced through the puncta, through the opening in the sac, and through the termination of the duct under the spongy bone, and have been retained for a longer or shorter period, according to the fancy, or theory, or plan of the surgeon. The first of the methods of introduction is abandoned, as already stated. By the ancients the passages in fault were got rid of altogether, being either cauterised or destroyed by escharotics.