seen to perforate the third lobe, and
this is the most frequent mode in which, under such circumstances, and
with instruments of the usual imperfect form, access may be gained to
the bladder for the relief of retention of urine. "The new passage may
in every respect be as efficient as one formed by puncture or incision
in any other way." (Fergusson.)

[Illustration]
Plate 60.--Figure 6

Fig. 7, Plate 60.--The three lobes of the prostate, a, b, c, are equally
enlarged. The prostatic canal is consequently much contracted and
distorted, so that an instrument on being passed into the bladder has
made a false passage through the third lobe. When a catheter is
suspected to have entered the bladder by perforating the prostate, the
instrument should be retained in the newly made passage till such time
as this has assumed the cylindrical form of the instrument. If this be
done, the new passage will be the more likely to become permanent. It is
ascertained that all false passages and fistulae by which the urine
escapes, become after a time lined with a membrane similar to that of
the urethra. (Stafford.)

[Illustration]
Plate 60.--Figure 7

Fig. 8, Plate 60.--The three lobes, a, b, c, of the prostate are
irregularly enlarged. The third lobe, a a, projecting from below,
distorts the prostatic canal upwards and to the right side.

[Illustration]
Plate 60.--Figure 8.

Fig. 9, Plate 60.--The right lobe, a c c, of the prostate appears
hollowed out so as to form the sac of an abscess which, by its
projection behind, pressed upon the forepart of the rectum, and by its
projection in front, contracted the area of the prostatic canal, and
thereby caused an obstruction in this part. Not unfrequently when a
catheter is passed along the urethra, for the relief of a retention of
urine caused by the swell of an abscess in this situation, the sac
becomes penetrated by the instrument, and, instead of urine, pus flows.
The sac of a prostatic abscess frequently opens of its own accord into
the neighbouring part of the urethra, and when this occurs it becomes
necessary to retain a catheter in the neck of the bladder, so as to
prevent the urine entering the sac.

[Illustration]
Plate 60.--Figure 9.

Fig. 10, Plate 60.--The prostate presents four lobes of equal size, and
all projecting largely around the neck of the bladder. The prostatic
canal is almost completely obstructed, and an instrument has made a
false passage t