254 TieWisDoM of GOD Part II- 



Things J that there being a diftance neceiTarily 

 required for the CoUedion of the Rays received 

 by the Pupil, viz, thofe that proceed from one 

 Point of the Objedl to one Point again in the bot- 

 tom of the Eye, the Retiita muft needs be fet at 

 a diftance from the cryftalline Humour j and 

 therefore Nature hath provided a large Room, 

 and fiird it with the pellucid vitreous Humour, 

 moft fit for that purpofe. 



I muft not omit a notable Obfervation concern- 

 ing the Place of the Infertion of the optick Nerve 

 into the Bulb of the Eye, and the reafon of it ; 

 which I owe to that learned Mathematician Pe^ 

 ter Herigon : Ncrvus opticus (faith he in his O/- 

 tica) ad latus ponitur^ ne pars imaginis in ejus fo-^ 

 ramen incidens piBurd car eat: The Optick Nerve 

 is notftuate directly behind the Eye, but on one fide ^ 

 lefi that Part of the Image that falls upon the Hole 

 of the optick Nerve Jhould want its PiBure, This 

 I do not conceive to be the triie Reafon of this 

 Situation y for even now as it is fituate, that Part 

 of the Objeft whofe Rays fall upon the Center, 

 or Hole of the optick Nerve, wants its Pifture, 

 as we find by Experience, that Part not being 

 feen by us, tho' we heed it not ; but the reafon 

 is, becaufe if the optick Axis fhould fall upon 

 this Center (as it would do were the Nerve feated 

 juft behind the Eye) this great Inconvenience 

 would follow, that the middle Point of every 

 Objedt we view'd would be invifible, or there 

 would be a dark Spot appear in the midft of it j 

 Z thus 



