[ 4°8 ] 
Grounds of this fourth Inconvenience ; which are 
thefe: 
It is not the exterior Integuments that ever hinder 
the Pafl'age of the Stone ; for they yield too eafily 
[to give any Obflacle]. The Septum Levator Ani is 
not more difficult to dilate from the Moment it has 
begun to be divided : Wherefore the real Obftacles 
to the Extraction of the Stone are, either the Bones 
of the ‘ Pelvis , the Bladder, or the Proftate. 
The Bones of the ‘Pelvis give an equal Obftacle 
to all the Sorts of lateral Operation : And even, ge- 
nerally fpeaking, in all the Methods of the low Ap - 
paratus , it is the fame Road, the fame Outlet, the 
fame Obftacle. 
The Bladder prefents as great an Obftacle in the 
fourth Sort of the lateral Operation as in the fecond, 
or in ours. In the firft, the Wound of the Bladder 
is made an Inch long ; in the fecond, the Bladder is 
laid bare for fome Lines, and then dilated the reft of 
the Way. In both thefe the Opening is the fame, 
when the Forceps is introduced. In extracting the 
Stone, you mult in both ftill dilate or tear as much 
as the Size of the Stone requires; and, confequently, 
in this refpeCt, the Difficulty is the fame. 
The Proftate and Neck of the Bladder are the re- 
maining Obftacles to the Extraction of the Stone. 
Thefe Parts are divided in our Method, and they are 
left whole in the lateral Operation of the fourth Sort. 
Now it is plain, and I have experienced it in the 
three Operations I did, that the Neck of the Bladder 
and the Proftate advance, while the Stone is extradit- 
ing, under the Pubis , and againft the interofleous 
Ligament of the Os Pubis , and there form a con- 
iidcrable 
