( =3^ ■) 



mid S, and, wlieiv llicy approacli nearer, at P or O, they become tliin- 

 ncr or fleiiJcrtr. Finally, upon an attentive examination of the cry- 

 ilalline humour, we Ihall be convinced, tliat its tranfparency is not to 

 be exceeded by any glals, although it confills of fo many thoufand 

 f-'laments, MJiich is moll wonderful ; and the more, if Me confidcr, 

 how cloleiy the filaments mult be united, that they may admit the 

 rays of light to pals througli tliem in (trait lines ; for otherwife, the 

 cryfcalline humour would not be pellucid, but would exhibit a white 

 appearance. 



In order to explain this formation of the cryflallinc humour flill 

 more plainly to fome curious gentlemen, I took a fmall tennis ball, 

 and woimd it clofe round about, with fome very fmall twine, confining 

 the twine by pins Ihick in the ball, in the pofition orcourfe which 

 the filaments take ; I then fpread over the whole Ibme flrong glue, 

 'and when it was dry, 1 took out the pins, and then the twine thus 

 v.'ound round the ball, gave a true reprefentation of the courfe of the 

 ■filaments as before defcribed. 



I have mentioned in the beginning of this Effa}-, that the parts 

 which I now plainly perceive are filaments, I then thought were 

 com])ofed of globules, and this, in fome filaments, did then feem to 

 me very apparent; but, not having feen the fame appearance uni- 

 formly in all, I now' conclude, that the filaments being (as before 

 jnentioned) m.ofc cloleiy united, it might hapi^en, that in the feparat- 

 ing them, fome fragments or particles of one, might ftick to another 

 of them, and thefe I might miJlake for globules. 



After this, I took the eyes of Iheep, hogs, dogs, cats, and other 

 animals, and examined their cryllalline humours, in the fame maimer 

 as I had treated the eyes of oxen ; but, neither in the fcales or coats 

 conllituting the cryilallme humours, nor in tlie difpofition of the 

 filaments, of which each coaf or fcale was compofed, did I perceive 

 jtiic lead difference. Moreover, I extraiflcd the cryficdline humour. 



