THE BILE. 143 



i 



radicles of the biliary passages, together with so-called mucus which 

 is derived from the epithelial lining of the greater trunks and the 

 gall-bladder itself. Its secretion is continuous, but liable to exacer- 

 bations which are essentially dependent upon the ingestion of food. 

 According to Heidenhain, the curve of secretion, in reference to 

 amount, shows two periods of greatest activity, which in the dog 

 correspond to the third to the fifth and the thirteenth to the fifteenth 

 hour, respectively, after the administration of food. This curve, 

 however, is further influenced by the character of the food ingested. 

 With an albuminous diet three stages of maximal secretion are 

 thus noted : The first after two to three hours, a second stage 

 after five to eight hours, and a third stage after twelve to fourteen 

 hours. With a diet of albumins and fats, on the other hand, the 

 period of greatest secretion occurs after eleven to twelve hours, 

 and with one of albumin and carbohydrates after from nine to 

 fourteen hours. These figures have reference to observations which 

 were made after the administration of only one meal in the twenty- 

 four hours. With two meals analogous results are obtained. The 

 individual periods, however, are shorter ; and as the number of 

 feedings is increased the secretion becomes more uniform, so that 

 with a meal every two hours no variations of moment can be 

 discerned. 



Amount. The amount of bile which is eliminated in the twenty- 

 four hours is variable even under normal conditions. In dogs from 

 2.9 to 36.4 grammes can be obtained pro kilogramme of weight of 

 the animal. In man the secretion apparently varies between 400 

 and 800 grammes ; but it is possible that these figures do not repre- 

 sent normal values. Ranke has estimated that a man weighing 75 

 kilogrammes secretes about 1050 grammes even in health. To a 

 certain extent the amount is influenced by the character of the food, 

 and it appears to be quite generally accepted that a diet rich in 

 albumins will call forth a greater secretion of bile, while the carbo- 

 hydrates are thought to diminish its amount, or are at least incapable 

 of increasing this, like the albumins. The fats, on the other hand, 

 are probably without effect in either direction. 



It was formerly thought that a number of drugs could increase 

 the flow of the bile, and physicians Avere wont to administer 

 cholagogues when they supposed that the secretion of bile was 

 deficient. This view has now been abandoned, as it has been defi- 

 nitely established that drugs are without effect in this direction. 

 The only cholagogue, indeed, if it may so be termed, is the bile 

 itself. This is readily understood, if we bear in mind that the 

 bile is essentially an excretory product. 



General Properties. The color of the bile differs in different 

 animals, and may vary from a bright yellow to an intense grass- 

 green, with various shades of brown and blue. In man it is usually 

 of a golden-yellow color, but it may at times appear bright green 

 ^even when perfectly fresh. 



