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circumftance that gave rife to Monf. Daviel's method of ex- 

 trading the cryftaliine. 



To overcome thefe real oestacles, care muft be taken, 

 firft, by a proper opening of the cryftaihne capfula, to give room 

 to the difcharge of this body ; next, to diflocige it from its fockct 

 or bed ; and laftly, to withdraw it to the pofterior and inferior 

 parts of the eye, at Icaft to place it below llie piipilla. Inftead 

 of the needles in ufe, I have mine flat, pointed, and edged like 

 lancets, and like them gradually encreafing in furface. The length 

 of the incifive part is to its greateft breadth nearly as three to two ; 

 from the broadcft part it rounds off gradually, and both the handle 

 and blade arc fhorter than thofe of the common catarad needle. 

 With this knife or lancet moiftened, the eye (if the left) is to be per- 

 forated in the fclerotica, at about two lines diftance from the cornea 

 lucida, at the external canthus. If for the right eye, and that 

 the operator is not ambo-dexter, a curvature may be made in the 

 inftrument, and the lancet fhould pierce the eye at the internal 

 canthus, and at fame diftance from the cornea tranfparens. Let it 

 advance in nearly a ftraight line (for it Jhould have a Jmall incli- 

 nation tmoards the piipilla) and it will then enter into the fide of 

 the capfula. The breadth of the inftrument alone will give a tole- 

 rable opening, which fhould be encreafcd by a gentle elevation 

 and deprefTion of the fides (not the point) of the inftrument. 

 Pufh the point after this to the other fide of the capfula, which 

 is alfo to be opened, but without injuring the procefTus ciliares. 

 Sufficient fpacc is now left for diflodging the catarad from its 

 bed, which the furrounding fluid will facilitate ^ but if we fail in 



our 





