George Walker ra) 
translucent and assumes a dark red color. The amount of ammonia 
used is determined by referring to the vessel in which the 25 ce. have been 
measured. ‘The gelatine in whatever proportion it is required—according 
as a thin or thick solution is desired—is dissolved in the distilled water, 
and the carmine solution is added to it. We then calculate how much 
acetic acid will be required for the amount of ammonia which has been 
used; this is measured and added, drop by drop, to the mixture which is 
constantly stirred. A sufficient quantity of water is then added to bring 
the amount up to a litre. I found that in this way I could always obtain 
a beautifully clear gelatine and was never annoyed by the failures and 
uncertainties belonging to the other method. 
ARTERIES. 
The prostate gland derives its arterial supply from the internal iliac 
arteries by means of four branches; the superior vesical, the inferior 
vesical, a small branch from the inferior hemorrhoidal, and a small termi- 
nal branch from the internal pudic artery. These vessels will be found 
illustrated in my paper published in 1899. The superior vesical, a 
branch from the internal iliac, which is given off high up, divides before 
reaching the bladder, into two fair-sized branches; the lower and smaller 
branch extends downward and supplies the vesical third of the prostate ; 
this branch is sometimes called the middle vesical artery. The inferior 
vesical, which is a large branch, is practically the main blood vessel of the 
prostate gland, and should be called the prostatic artery for, in the 
majority of instances, it does not send any branches to the bladder. The 
major part of the gland is supplied by this vessel; it courses along the 
vesicorectal fascia and meets the prostate at its lower border, where it 
usually divides into seven branches, four of these enveloping the anterior, 
and three the posterior surface. The posterior are about one-half the 
size of the anterior branches. These vessels are situated in the capsule of 
the gland and envelop it as the fingers of one’s hand would do in clasping 
a round object. From these trunks a number of smaller ones are given 
off, so that a very close arterial network is formed over the surface of the 
gland. The branch from the inferior hemorrhoidal is not constant; in 
fact, it appears to be more often absent than present. When it is seen, 
it occurs as one or two small branches which meet the prostate in its 
urethral half, and extend over the surface as fine vessels which anastomose 
with the vesical artery. The internal pudie branch is fairly constant. 
It extends along the membranous urethra and plunges directly into the 
prostatic substance usually without giving off any branches to the surface. 
