THE LIVER. 1047 



bowel opened in three or four days, when adhesion of the bowel to the edges of the wound has 

 taken place. 



Iiir/niiiit1 <-<>l>ti>my is preferred by many surgeons in those cases where there is no urgent 

 obstruction, aivl where, therefore, there is no necessity to open the bowel at once. The main 

 reason for preferring this operation is that a spur-shaped process of the meso-colon can be formed 

 which prevents any fecal matter finding its way past the artificial anus and becoming lodged on 

 the diseased structures below. The sigmoid flexure being almost entirely surrounded by peri- 

 toneum. a coil can be drawn out of the wound and the greater part of its calibre removed, leav- 

 ing the remainder attached to the meso-colon, which forms a spur, much the same as in an 

 artificial anus caused by sloughing of the gut after a strangulated hernia, and this prevents any 

 fecal matter finding its way from the gut above the opening into that below. The operation is 

 performed by making an incision two or three inches in length from a point one inch internal to 

 the anterior superior spinous process of the ilium, parallel to Poupart's ligament. The various 

 layers of abdominal muscles are cut through, and the peritoneum opened and sewn to the 

 external skin. The sigmoid flexure is now sought for. and pulled out of the wound and fixed by 

 passing a needle threaded with carbolized silk through the meso-colon close to the gut and then 

 through the abdominal wall. The intestine is now sewn to the skin all round, the suture passing 

 only through the serous and muscular coats. The wound is dressed, and on the second to the 

 fourth day. according to the requirements of the case, the protruded coil of intestine is opened 

 and removed with scissors. 



THE LIVER. 



The Liver (Hepar) is a gland intended for the secretion of sugar and bile, 

 remarkable for its size, equalling that of all the other glands put together, and 

 for its connections with the system of the portal vein which ramifies in its sub- 

 stance. It may be described under two heads: (1) External conformation; (2) 

 Structure or Histology. First we shall study its sit- 

 uation. its volume, its weight, its consistence and color. 

 its form, its relations, and its means of fixation. This 

 organ fills almost all the right hypochondrium. a great 

 part of the epigastrium, and advances into the left hypo- 

 chondrium as far as the mammary line in the neighbor- 

 hood of the spleen. It is situated, consequently, below 

 the diaphragm, which separates it from the lungs and 

 heart : above the stomach, duodenum, transverse colon. 

 and small intestines, which form a sort of pillow ; and 

 behind are the right false ribs, which protect it. In an 

 embryo of three weeks this organ fills the greater part 

 of the abdomen (Fig. 663). During the first half of 

 intra-uterine life its anterior border is below the umbil- 

 icus. In a child of six or eight years it gets behind the 

 free border of the right false ribs. In the adult its 

 average transverse dimension is 28 cm. (eleven inches), FIG. ees. Embryo of twelve 



,. . . -. / -i i \ weeks with open thoracic and 



its antero-posterior dimension is 20 cm. (eight inches), abdominal cavity in which the 

 and vertical dimension is 6 cm. (two and a half inches) 1111 ' 



(Sappey). Quain's figures are greatest vertical diam- 

 eter on the right lobe, five to seven inches, greatest transverse is one or two 

 inches more ; its greatest antero-posterior diameter is above the right kidney. 

 four to six inches, and in front of the vertebral column is two and a half to four 

 inches. All this varies with the individual, the amount of blood contained, and 

 the state of digestion and pathological state. 



Its volume is 90 to 100 cubic inches. 



The absolute weight of the liver is proportional to its volume and amount of 

 blood contained. The average is in bloodless livers 1.451 kg. : in physiological 

 livers containing blood, 1.937 kg., or about one-thirty-second of the body-weight. 

 At birth it is one-eighteenth of the body-weight. This is 50 or 60 ounces avoir- 

 dupois in the male, a little heavier than the brain, and 40 to 50 ounces in the 

 female. Its specific gravity is 1.046. The consistence of the liver is soft, but 

 harder than that of other glands. It has a certain friability. Its tissue is more 

 easily crushed than depressed. 



The physiological color is a dark, reddish brown. In the young it takes on a 



