the Thilomalhic Society of Parts. 128 



For the fluid cataract, the same instrument and nearly the 

 same process of operation are requisite; with this difference, that 

 we have only to attend to the crystalline capsule, which is ge- 

 nerally opaque. 



Sir \Vm. Adams, for the operation of capsular cataract, prefers 

 a needle which differs a little from that which has been de- 

 scribed by Scarpa, and from that which we make use of for the 

 operation by depression. The ojierating process consists in 

 cutting the capsule into stripes, and subjecting it to the ab^orb- 

 eut powers of the chamber of the eye. When the capsule is' 

 too thick, and it is difficult to tear it, Sir Wm. Adams contents 

 himself with detaching it from its adhesions. The capsule con- 

 tracts of itself, and occupies, until it is entirely absorbed, a point 

 of the posterior or anterior chamber : as, on account of its 

 weight, it occu])ies the lower part only, it does not oppose the 

 passage of the rays of light. If the capsule adheres to the pos- 

 terior face of the iris. Sir Wm. Adams, instead of dividing it into 

 slips, and making it pass into the anterior chamber as Scarpa 

 recommends, contents himself with separating it with great care 

 from all its adhesions, and leaving it merely attached by a point 

 in its circumference to the ciliary processes, — so that it may not 

 move, but remain fixed to the posterior face of the iris, where 

 it becomes absorbed more or less speedily. Sir Willliani 

 Adams has seen some of these capsules, when placed in the 

 anterior chamber, remain upwards of two years Vi'ithout 

 occasioning any accident, or even injuring vision. In ccneral 

 it is very advantageous to separate it into several portions, 

 for then its absorption is infinitely more speedy. Sir William 

 Adams has a particular process for operating upon solid 

 cataract in old persons: at this age the centre of the crystal- 

 line is so hard that the needle cannot make any impression 

 upon it ; in this case Sir William Adams makes use of an in- 

 strument a little stronger, with which he cuts tlie crystalline by 

 vertical incii^ions, taking care to avoid any change in the situa- 

 tion of the part : the fragments are pushed into the anterior 

 chamber: the place which they occupy is filled by the aqueous 

 humour, which softens what remains of the crystalline, and ad- 

 mits of its being cut entirely by incisions in a second or a third 

 operation, at the same lime that it ])revents the crystalline from 

 approaching the iris. There ought not to be a long interval 

 between the operations ; for the nucleus of the crystalline might 

 either be detached and press upon the iris, causing irritation, 

 or, passing into the anterior chamber, where on account of its 

 hardness it could not be absorbed, would require for its ex- 

 traction the incision of the cornea. As to the capsular cataract 

 with transparency of the crystalline, (a cataract whigh ought 



