114 OF THE ANIMAL STRUCTURE 



of the tliorax in their places ; in particular to hinder one 

 lobe of the lungs from incommoding another, or the parts 

 of the lungs from pressing upon each other when we lie on 

 one side.* 



3. The liver is fastened in the bod}^ by two ligaments ; 

 the first, which is large and strong, comes from the cover- 

 ing of the diaphragm, and penetrates the substance of the 

 liver; the second is the umbilical vein, which, after birth, 

 degenerates into a ligament. The first, which is the prin- 

 cipal, fixes the liver in its situation, whilst the body holds 

 an erect posture ; the second prevents it from pressing up- 

 on the diaphragm when we lie down ; and both togethei' 

 sling or suspend the liver when we lie upon our backs, so 

 that it may not compress or obstruct the ascending vena 

 cava,t to which belongs the important office of returning 

 the blood from the body to the heart. 



4. The bladder is tied to the navel by the urachus trans- 

 formed into a ligament ; thus what was a passage for the 

 urine to the foetus, becomes after birth, a support or stay 

 to the bladder. The peritonaeum also keeps the viscera 

 from confounding themselves with, or pressing irregularly 

 upon the bladder ; for the kidneys and bladder are contain- 

 ed in a distinct duplicature of that membrane, being there- 

 by partitioned off from the other contents of the abdomen. 



5. The kidneys are lodged in a bed of fat. 



6. The imncrcas or sweetbread is strongly tied to the 

 peritonaeum, which is the great WTapping sheet, that en- 

 closes all the bowels contained in the lower belly. J 



7. The spleen also is confined to its place by an adhe- 

 sion to the peritonaeum and diaphragm, and by a connexion 

 v/ith the omentum. § It is possible, in my opinion, that 

 the spleen may be merely a stuffings a soft cushion, to fill 

 up a vacancy or hollow, which, unless occupied, would 

 leave the package loose and unsteady ; for supposing that 

 it answers no other purpose than this, it must be vascular, 

 and admit of a circulation through it, in order to be kept 

 alive, or be a part of a living body. 



8. The omentum, epiploon, or caul, is an apron, tuck- 

 ed up, or doubling upon itself, at its lowest part. The up- 

 per edge is tied to the bottom of the stomach, to the spleen, 

 as hath already been observed, and to part of the duode- 

 num. The reflected edge also, after forming a doubling, 



* Keill's Anat. p. 119. ed. 3. t Ches. Anat. p. 162. 

 t-Keill's Anat. p. 57. § Ches. Anat. p. 167. 



