KIDNEY. 



contained in an iiigjuiiial or vaginal hernia. Its fituation 

 is not always perfeiAly ftraight, but fometimes, as Celfiis 

 has obfervcd, rather inclined to the left. It is retained in 

 its fituation by cellular fubilance, which furrouuds it on 

 all fides, and by other means, whicli will be defcnbed pre- 

 fently. 



The capacity of the organ differs according to the age, 

 fex, and difeafos. It is much greater, in proportion to the 

 fi/e of the bjdy, in children than in adults : it diininillies 

 afterwards as it (inks in the pelvis. It is larger in perfons 

 who have tlie habit of retaining the urine for a long time, 

 than in others ; and on this account it may be larger in 

 fome females. In cafes of retention of urine it fomctimcs 

 is fo enlarged as to hold feveral pints : and it is diminifhed 

 in a corrcfponding degree in other affcAions, as when it is 

 irritated by the conftant prefence of a ftone, or by any other 

 caufe. We can hardly aifign any particular capacity as the 

 natural one, there is fo much variety in different individuals : 

 a healthy perfon may void, at one time, from half a pint or 

 L'fs to two pints. 



The figure of the bladder, in an adult male, is nearly 

 that of an oval, ratlier flattened from before backwards, with 

 the large extremity placed downwards and a little backwards, 

 and the fmaller in tlie contrary du^ection. In females, and par- 

 ticularly in thofe who have had many children, it is not fo 

 high, but broader in the tranfverfe direftion. It is very 

 elongated, and nearly cylindrical, in the foetus, at which 

 time its extremity, formed by the urachus, approaches the 

 navel : its length is three times its breadth, and its tranf- 

 verfe diameter is nearly equal to the antero-pofterior. At 

 no long period after birth chefe dimenfions change, the blad- 

 der becomes more rounded, and affumes a fomewhat pyri- 

 form figure ; and, as the child grows, the figure ap- 

 proaches more and more to the oval. Several anatomiffs dif- 

 tinguilh in the bladder a fuperior portion, which they call 

 the fundus ; a middle part, or body of the bladder ; and 

 an inferior divifion, comprehending the lower furfaces and 

 the neck. We (hall divide the organ into two furfaces, an 

 external and an internal. 



The external furface may be naturally divided into fix re- 

 gions ; tifs. an anterior, apollerior, a fuperior, an inferior, 

 and two lateral, or right and left. 



The anterior, which is Ilightly inclined forwards, is 

 bounded above by the urachus, and below by tlie neck of 

 the bladder. At its lower part are feen two fm ill fibrous 

 fafciculi, called anterior ligaments of the bladder. They 

 have a hori'/ontal direction, and are attaciied to the back of 

 the fymphyfis pubis in front, to the fuperior portion of the 

 neck of the bladder, and to the prollate behind. This 

 region then correlponds to the flattened pollerior furface 

 of the offa pubis and their lymphyfis, to which it is con- 

 nefted by a loofe cellular fubilance. When the organ is 

 empty, or moderately filled, it does not alcend above the 

 bone ; but in the diilended Hate it rifcs out of the pelvis, 

 and correfponds imm.edia'cl) , without the interpofitiou of 

 the peritoneum, to the abdominal mufcles. Hence, at this 

 lime it may be perforated by a trochar, or opened for the 

 extraftion of a ilone, without expofing the patient to an 

 effufion of urine in the abdominal cavity. 



The pollerior furface, flightly inchned upwards, is con- 

 vex, fmooth, entirely covered by peritoneum, contiguous to 

 the rectum in the male, and to the uterus in ihe female fub- 

 jctt, and to the inferior convolutions of the fmall intelline in 

 tolh fexes. 



■ The lateral regions, which are broader below than above, 

 are covered by peritoneum in their pollerior portion only : 

 in front they are connected to the lides of the cavity of the 



pelvis by a large quantity of cellular tiflue. The umbincal 

 arteries, and the vafa deferentia, pafs along them. 



The fuperior region is commonly called the fundus of the 

 bladder ; it correfponds to the convolutions of the fmall 

 intelline, and affords attachment to the fuperior ligament of 

 the bladder. The latter is compofed of the urachus and 

 of the two umbilical arteries, each of which is here in- 

 cluded in a fmall faLiform portion of peritoneum. The ura- 

 chus, occupying the middle of tliii ligament, appears in the 

 adult under the form of a whitiih librous cord, extended 

 from the fundus of the bladder, on the external furface of 

 the peritoneum, to the umbilicus, where it is confounded with 

 the aponeurofes of the tranfverfe mnfcles. It is about as 

 thick as a fmall quill at the bladder, but it grows gradually 

 fmaller towards the navel. It poffelfes no interior cavity, 

 and feems capable of no other nfe than that of fixi'g the 

 bladder in its fituation. Inilead of being folid and liga- 

 mentous, it is faid fometimes to form a true can.al, by means 

 of which the urine efcapes at the navel; this un .f lal ap- 

 pearance, which we have never feen, is faid to arile from 

 obllruition at the neck of the bladder, and to ccafe as foon 

 as the urine flows through the urethra. 



The elongated figure and great elevation of the bladder 

 in the foetus, make the urachus very fliort ; it then forms a 

 canal, beginning from the upper part of the bladder : thence 

 it afcends to the umbilicus, becoming at the fame time con- 

 trafted. Laftly, it enters this ring with the umbilical ar- 

 teries, and is continued into the cord : according to Haller, 

 it may be filled with mercury for an inch, or an inch and a 

 half. Farther on, it is faid to be divided into feveral fila- 

 ments, which are loft on the arteries : but Mr. Cruikfiiank. 

 Hates that it is continued, in the form of a very flender 

 thread, throughout the cord. In quadrupeds it is manifellly 

 hollow, and paffcs through the cord to a membranous bag 

 called the allantois, in which it ends. Its diameter ii vari- 

 able : in general it is not more than one-third of a line in 

 breadth, and it opens into the bladder by an orifice, which 

 is fo fmall and difficultly found, that many good anatomills 

 have altogether denied its exiltence Sometimes it is confi- 

 derably larger in this fituation. Haller fays that he has 

 expreffed from it a drop of gelatinous lymph, and others 

 fpeak of urine as contained in it. Its confillence is firm ; 

 it feems to be formed by a prolongation of the internal coat 

 of the bladder, inclofed by long and hard fibres continued 

 from the mufcular coat. It is clofed, and becomes folid and 

 ligamentous iome time before birth : its cavity is obliterated, 

 like that of the umbilical vcfl'els, and it can no longer be 

 dilated, or receive urine. Sometimes, however, it remains 

 open : Haller introduced a hog's brilUe into it in the adult,- 

 and he mentions gravel being contained in it in another in- 

 ftance. In 17^87, lays Boyer, I difletted the bladder of a 

 man thirty-fix years old, whofe urachus formed a canal an 

 inch and a half long, and contained twelve urinary calculi of 

 the fize of millet feeds. I aCcertained that the containing 

 tube was not a facculus or elongation of the internal coat 

 through the mufcnlar tunic. Thefe examples of a hollow 

 in the urachus of the adult are very rare. 



As the exillence of a canal in this part is fometimes de- 

 nied, we fubjoin the following exprefs tellimony of Haller 

 on the fubjccl. " Doubts have been entertained whether 

 the urachus be hollow, fmce we often ilnd that nothing 

 palfes into it, when the bladder is diilended with air or mer- 

 cury ; and feveral good anatomills have found no canal. 

 But the repeated invelligations of this matter by myfelf, 

 and by one of my pupils, have plainly fliewn that a foramen 

 leading into the urachus exitls at 'he top of the bladder in 

 die liuman foetus. Whea the furroundiug. cellular fubilance 



