76 OPACITY OF THE CORNEA. 



thalmic inflammation. I once had occasion to perform — as I shall 

 hereafter give an account of — an operation simply on the lachrymal 

 caruncle, and the consequence was violent conjunctival inflamma- 

 tion and ophthalmia, and thick and complete nebulosity of the 

 entire cornea. When nebula, from the changes which in the course 

 of time — unless it become at once absorbed — it gradually under- 

 goes, turns from a hazy cloudiness to a pearly or fleecy whiteness, 

 it takes the technical appellation of albugo. 



The opacity we have been speaking of arises from the deposition 

 of lymph between the conjunctival covering and the cornea ; unless 

 the wound may happen to have been deep, and then probably, in 

 its immediate vicinity, interstitial deposit within the lamellated 

 substance of the cornea has taken place as well. When the cornea 

 becomes obscured in consequence of ophthalmia, it is probable that 

 the chief effusion is seated inwardly, between its lining membrane 

 and lamellse, and that serous or other eff"usion has taken place 

 likewise between the lamellae themselves. 



The Removal of Opacity will, in general, take place with 

 the dispersion or cure of that which gave rise to it, or will com- 

 monly soon follow that result. With the inflammation arising 

 from injury commences and grows the opacity, and with its decline 

 the opacity begins to decrease ; and though it may remain some 

 time after all the inflammation has disappeared, yet in the end 

 will it, generally without assistance, become absorbed. Should 

 there, however, be any sluggishness of the absorbent powers appa- 

 rent, from the disposition of the opacity to remain unaltered either 

 in colour or dimensions, we may set these powers in fresh action 

 often by the use of stimulating powders, ointments, or solutions, 

 and, in some obstinate cases, may derive a good deal of benefit from 

 the application even of caustic substances. Chloride of soda and 

 common glass finely powdered are often used with benefit under 

 such circumstances : but the best application is a solution of nitrate 

 of silver — from ten grains to a drachm even to the ounce of distilled 

 water : indeed, in some instances, good has been done by touching 

 the opacity with the pencil of nitrate of silver. From five grains 

 to a scruple of bichloride of mercury to the ounce of water is another 

 form of injection. 



