SOME ECONOMICS OF NATURE. 35 



dered capable of being absorbed into the system. Instead of waiting 

 for a lengthened period for the arrival of this important part of its 

 commissariat, the body receives such food- elements soon after diges- 

 tion begins. The fats, starches, and sugars are, on the contrary, 

 passed onwards to be digested in the intestine. They become 

 available for nutrition only after several hours of digestive work. 

 The principle of "small profits and quick returns" itself an econo- 

 mical and commercially satisfactory mode of doing business is 

 illustrated in the digestive transactions of the body. That which is 

 urgently required for the frame is quickly supplied, while the, in one 

 sense, less important foods are left for later absorption. 



In this economical work the liver plays an important part. Long 

 ago in physiological history that organ was regarded simply as a bile- 

 making machine. The bile, thrown upon the food just after it leaves 

 the stomach, was regarded as an all-important digestive fluid. To-day 

 we have entered upon entirely new ideas of the liver's work. As 

 Dr. Brunton has aptly put it, the liver is no more to be regarded as 

 a mere bile-maker than the sole use of an Atlantic liner is to be 

 found in the manufacture and display of the water-jets which issue 

 from the sides of the ship as the waste products of her engine-work. 

 The liver is really a physiological constable placed at the entrance of 

 the blood circulation. Into it are swept digested matters. These 

 are further elaborated and changed so as perfectly to fit them for 

 entrance into the blood. When the functions of the liver are 'sup- 

 pressed or rendered inactive, elements of deleterious kind are appar- 

 ently allowed to enter the circulation, and thus produce all the 

 symptoms of the body poisoning itself. This being so, we begin to 

 see that the bile is really a mere by-result of the liver's work, as the 

 condensed water of the steamer is the consequence of the real func- 

 tion of the vessel. Bile is a waste product, and as such it is 

 discharged into the intestine and thus excreted. 



But natural economics rule life's actions here as elsewhere. For 

 the apparently useless bile, Nature finds a use. It is discharged 

 upon the food, and mingles with the half-digested nutriment. It 

 has come to exercise a digestive or dissolving action upon fats, a 

 function aptly illustrated by the household use of the " ox-gall " to 

 remove grease stains in the house-cleaning periods of human exist- 

 ence. Moreover, the bile would appear to aid in promoting the 

 muscular contractions of the intestine, and in thus expediting diges- 

 tive action. It may possess other duties still ; but enough has been 

 said to show that the economy which rules living functions is pro- 

 bably nowhere better illustrated than in the utilisation of bile, as a 

 waste-product, in the normal discharge of the digestive act. 



Turning, lastly, to the nervous system and its work, we may find 

 exemplified equally manifest phases of economical action. When 



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