incision for the
purpose of parting the loose cellular tissue; and any of the more
resisting structures, such as the transverse and levator ani muscles,
are to be divided by the knife. Deep in the forepart of the wound, the
position of the staff is now to be felt for, and the structures which
cover the membranous portion of the urethra are to be cautiously
divided. Recollecting now that the artery of the bulb passes anterior to
the staff in the urethra on a level with the bulb, the vessel is to be
avoided by inserting the point of the knife in the groove of the staff
as far backwards--that is, as near the apex of the prostate--as
possible. The point of the knife having been inserted in the groove of
the staff, the bowel is then to be depressed by the left fore-finger;
and now the knife, with its back to the staff, and its edge lateralized
(towards the lower part of the left tuber ischii), is to be pushed
steadily along the groove in the direction of the staff, and made to
divide the membranous part of the urethra and the anterior two-thirds of
the left lobe of the prostate. The gland must necessarily be divided to
this extent if the part of the urethra which it surrounds be traversed
by the knife. The extent to which the prostate is divided depends upon
the degree of the angle which the knife, passing along the urethra,
makes with the staff. The greater this angle is, the greater the extent
to which the gland will be incised. The knife being next withdrawn, the
left fore-finger is to be passed through the opening into the bladder,
and the parts are to be dilated by the finger as it proceeds, guided by
the staff. The staff is now to be removed while the point of the finger
is in the neck of the bladder, and the forceps is to be passed into the
bladder along the finger as a guide. The calculus, now in the grip of
the forceps, is to be extracted by a slow undulating motion.

The general rules to be remembered and adopted in performing the
operation of lithotomy are as follow:--1st, The incision through the
skin and sub-cutaneous cellular membrane should be freely made, in order
that the stone may be easily extracted and the urine have ready egress.
The incision which (judging from the anatomical relations of the parts)
appears to be best calculated to effect these objects, is one which
would extend from a point an inch above the anus to a point in the
posterior perinaeal space an inch or more below the anus. The wound thus