134 ORIFICE OF THE URETHRA. 



From the quantity and the regular diffusion of this mucus on 

 the surface of the bladder, there is the greatest reason for be- 

 Ueving that it is effused from every part of the surface ; and it 

 is a question that has not been decided whether it is discharged 

 from glandular ducts too small to be perceived, or from the 

 exhalent extremities of the blood-vessels. It is probable that 

 the use of it is to defend the internal coat of the bladder from 

 the acrimony of the urine. 



The symptoms of a stone in the bladder, as well as of several 

 other diseases, evince that this coat is endued with a great 

 degree of sensibility. 



It is evident that the essential parts in the general structure 

 of the bladder are the muscular coat and the internal coat last 

 described : but in addition to this account of them, there are 

 some other important circumstances to be noted in the descrip- 

 tion of this organ. It has been already stated, that the form 

 of the bladder was an irregular oval, although it was somewhat 

 varied in different persons.* The oval form is not much 

 altered at the part called the neck of the bladder, where the 

 urethra passes off from it. The orifice of the urethra is situated 

 anteriorly near the lowermost part of the bladder. On the lower 

 surface of the urethra, at its commencement, and on the bottom 

 of the bladder, immediately connected with the urethra, is 

 situated the Prostate Gland, (to be hereafter described with 

 the organs of generation,) which is a firm body, that adheres 

 strongly both to the bladder and urethra. This circumstance 

 gives particular firmness and solidity to that part of the bladder. 

 It has also been observed, that the bladder is attached firmly 

 to the ossa pubis, at its neck, about the origin of the urethra. 

 Each of these circumstances has an effect upon the orifice of 

 the urethra ; and when the bladder is opened, and this orifice 

 is examined from within, it appears to be kept open by the 

 connexion of the bladder with the prostate, and has been very 

 justly compared to the opening of the neck of a bottle into the 

 great cavity of that vessel.f 



* In the female, the vertical diameter of the bladder is less than in the male. 

 Its transverse diameter is greater in consequence of the greater width of the 

 pelvis in the female. — p. 



f The late M. Lieutaud, and after him the French anatomists of the present 



