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[ 129 ] 



iris a line higher than the ligamentum ciliare. If you perforate 

 another eye a line and an half higher up on the cornea, it will 

 juft glide over the pupilla, and from this to the top of the cornea 

 within is another line. If from the fummit of the cornea a 

 ftraight line be drawn, and parallel to one from the rife of the iris, 

 i. c. the ligamentum ciliare at the fides of the eye, the diftance 

 will be found to be three lines and an half Thus the diftance 

 between the rife of the iris and the pupilla or its upper extremity 

 is generally two lines and an half, oftener more, meafured 

 from either canthus ; but from the middle of the fuperior 

 and inferior parts of the eye, as it lies in the orbit, a line 

 Icfs. 



Idea of adherent CataraSls exploded, real Difficulties attendant on. 

 depreffiirg Caiara&s demonjlrated, with the moji rational Means of 

 overcoming them. 



Brisseau, Maitre Jean, Heifter, and, in fhort, all oculifts, 

 whilft, as anatomtfs, they inform us that the cryftalline is fur- 

 rounded by a fine pellucid membrane ; as operators, they arc 

 careful to tell us that the cataraB frequetitty adheres to different 

 parts of the iris. Heifter, though his treatife De CataraSla merits 

 high applaufe, yet feems fo perfuaded of this imaginary 

 adhefion ! that, in his furgery he direds, when it is found 

 fo ftrong as not to be feparated by the needle, to perforate the 

 centre of the cryftalline, in hopes of giving fome fmall admiflion 

 to the rays of light. Warner who, we fhould fuppofe always 

 paid particular attention to this organ, though he tells us that 



S the 



