(togo) 
Bye;the*Tqueous htimour will run to the Tunica Cornea^ and 
make vviinkles^which will hinder the Pidlure from being diftin(5l: 
Befides, he that looks in at this aperture, will hinder theRayes 
of the Obje6l from palling into the Eye^ and he fball fee nothing 
there but his own image. But if you mean, that the Tumca Cor- 
nea^oxAA be wholly taken off, there will not then be diftance 
enough between the chrjflallm and thtRetim^ to make the Pi- 
durediftinft. In conclufion, I do not believe this Experiment 
can be made, much lefs that it is to be difcerned whether this Pi- 
dure be formed on the anteriour or pofteriour furfacc of the Reti- 
fja:^CmcQ the thicknefsof it is lefs than half aline, or the i^th 
part of an inch> and there is reafon to believe, that you have 
trufted to the report of fome other concerning this Experiment i 
or that you have believed the images which appear in the Eyes to 
be painted on the iJ^/i/a^,whereas they proceed from the reflexi- 
on made on the exteriour of the Cornea, 
Yonx fecond Experiment is true and eafie to be made , but ac- 
cording to you it were impoflible 5 for, fince you hold, that it is 
on the anteriour part of the Retindy that the Pidure is feen , and 
that you have elfewhere faid, that one cannot well fee through 
this Membrane , it follows , that you cannot fee this P;(5i:ure 
through the thicknefs of the Retina 5 but becaufe I believe, 
there remains tranfparency enough in that part of the Retina 
which is not exposed to the Air, I doubt not but the Pidure may 
be feen on the pofteriour part of it, after it is become fufHciently 
opake,though in a living Animal this Pidure paffeth as far as the 
Chomidesj as it hath been already proved : and if the Retina it 
felf were taken away, and there remained only the vitreous hu- 
mour, you might notwithftanding fee the inverted Pi(Sure of the 
Windows toward the bottom of the Eye, if you held it at the 
farther fide of the room 5 in the fame manner as the Pidure is to 
ht ktn \n the Foetid oi the fpherical Glafs-bottle fiU'd with wa- 
ter, though it feem to be on the exteriour furface of theGlafs; 
and by confequcnce this Experiment proves not the opacity of 
the Retina. 
In your third Objedion you quote, what I faid, a little other- 
wife than I fpokc it 5 for I put in my Writing, that the Retina 
was about half a line in thicknefs^and not half a line frecifely 5 
which 
