IMPROVED. lie 



The Vitreous or Glaffy Humour has a very 

 fine and thin Membrane or Coat with which it is 

 covered. This Membrane is adherent or joining to 

 the Ligamentum CiJiare, and no doubt has Blood- 

 Veflels ( as well as all the other Membranes of the 

 Body, which mull be nourifhed by Blood- Veffels,) 

 from thence, although fo fine and fmall that they 

 are not to be feen even with a Microfcope. Yet 

 this need not feem ftrange when we confider that 

 thofe of the Cornea, though they are much 

 larger, are not to be feen, till they become turgid 

 or fwell in an Opthalmia or Inflammation of the 

 Eye ; or even thofe of the Tunica adnata or white 

 of the Eye, till inflamed, as I have fa id. Now 

 whether there is any Communication between the 

 Vitreous Humour and the Gryftalline, is what Ana- 

 tomifts cannot determine : But this is plain, to wit, 

 that its Membrane or Coat is not only continued or 

 adherent to the Liga?nentufn Ciliare, but likewife 

 to the Tunica Aranea or Membrane which imm.e- 

 diately covers the Cryftalline Humour, which Tuni- 

 ca Aranea. is the Capfula of the Cryftalline lately 



difcovered by Dr. T- r,. as I have jull before 



hinted. 



The Optick Nerves pierce the Globe of the Eye The opticfc 

 a little on the Infide of the Qptick Axes. Their ^^^^^^•. . 

 External Coat, which is a Produaion of the ^^^^'"^ and Term'il 

 Mater, is continued to the Sclerotis or that Part'n-tion of 

 of the Eye next under the White ; as their Inter- c heir Coats, 

 nal from the Pia Mater is to the Choroides, which 

 ia the Coat next under the Sclerotica, and their Me- 

 dullary Fibres pafiing through all, are expanded in- 

 to the Retina, upon v/hich the Images of Objedls 

 are painted. The Center of this Expanfion is in- Cenrer of 

 fenfible, and all Rays which fall upon it are lofl:,; he Retina 

 and confequently that Point of the Objedl from ^"^'-"^^^^^• 

 which thefe Rays come is invifible to the Eye: 

 The Reafon of which proceeds probnbly from the TheReafon 

 Blood-Veflels, which enter with the Optick Nerve, alTigncd. 

 and cover thk part of the Retina.. But, whatever 



its 



