C 53 ° ] 
XC. ExtraSls of two Letters 0/* Thomas Hope, 
M D. to John Clephane, M . D. F. R . S . 
concerning Monjieur DavieFj Method of 
couching a Cataradl. 
Read Nov. i6,^( INCE I received your laft, I had 
I752 ’ heard of a new method of performing 
the operation for the cure of the cataradl, but did not 
care to fay any thing of it, until I had feen it myfelf, 
and had inquired into the fuccefs of it. M. Daviel, 
a furgeon of this place, was the firft, who, in 174?, 
began to put it in practice, and has at laft brought it 
to perfe&ion ; of which he has given a memoir to 
the Academy of Sciences of ny operations, 100 of 
which have fucceeded. A few days ago I faw him 
perform it on two perfons, of which take the follow- 
ing defcription : 
After having placed the patient in a right light in 
a chair, he places himfelf over-againft, and fome- 
what higher than, the patient: an afliftant holds the 
head fteady, another keeps the upper eye-lid open $ 
he, with his left hand, keeps open the lower eye-lid. 
Then he takes an inftrument like a lancet, of a myrtle- 
form point, a little crooked upwards, and fixed in a 
handle, and, making the patient look upwards, he 
pierces the cornea tran/parens at its lower circumfe- 
rence, juft where it joins the fclerotica , conveys the 
point of the inftrument between the cornea and iris 
upwards, beyond the pupil ; he enlarges this opening 
on each fide by the fame inftrument : he then takes 
out 
