ADDITION, BY THE TRANSLATOR. 



THE preceding Eflay is one of tlie moft curious, and the Tranf- 

 lator conceives, that his Readers will deem it the molt interelling, of 

 any in this Work ; forafmuch as it rel"pe6ls the choicefl corjxireal 

 gift of God to his creatures, the Blelling of Siglit : and, for the 

 information of thofe, who are not acquainted with the particular ftruc- 

 ture of that wonderful Organ, the Eye ; the follow ingdefcription of 

 it is fubjoined, taken from Mr. Adams's Eflay on Vifion, a i'mall 

 Treatifc, well wortliy the perufal of every one. 



"Of the Globe of the Eye. 

 " If the confliai(R:ion of the Univerfe were notfo evident a proof of 

 " the exiftence of a fupremely wife and benevolent Creator, as tO' 

 ** render particular arguments unneceflary, the ftru6lure of the eye 

 " might be offered as one, by no means the leaft ; this inftance, 

 " among numberlefs others, demonftrating, that the bcft ])erform- 

 " ances of art are infinitely lliort of thofe w^hich are continually pro- 

 " duced by the Divine Mechanic. 



" The globe of the eye, or the organ of fight, may be defined in 

 " general as a kind of cafe, confifting of feveral coats, containing 

 " three pellucid humours, which are fo adjufted, that the rays pro- 

 " ceeding from luminous objc6ls, and admitted at a hole in the fore 

 " part of the eye, are brought to a focus upon the back part of it, 

 " where they fall upon a loft pulpy fubllance, from whence the mind 

 " receives it's intelligence of vifible objefts. 



" It is not to be expected, that any account given of the eye can be 

 " altogether accurate ; for as it is impoflible to examine all the 

 " parts of the eye whilft in a natural and living ftate, fo it is alfo- 

 " nearly impoflible, when it is taken out of its focket, to preferve 



