The Body-Machine and Its Work 329 



that most of our nourishment is taken into the blood or the 

 lymph. The rest passes on into the "large intestine," a very 

 much wider tube at its lower extremity. 



It is just at this junction-point of small and large intestine 

 that the vermiform appendix is given off from the tube. Its 

 opening into the bowel is very narrow, and sometimes bits of 

 hard food, such as fruit-seeds, get into it and set up inflamma- 

 tion. Now in certain vegetarian animals like the rabbit the 

 appendix is at the end of a large and useful blind alley or ciecum. 

 A good deal of vegetable matter is wrapped up in cell-walls of 

 cellulose, and the digestive juices we have described have very 

 little power to deal with cellulose. It has to be broken up by 

 bacteria, in such a chamber as the rabbit's blind gut or ca?cum. 

 The human vermiform appendix is a remnant of the large maga- 

 zine in which some coarse-feeding ancestor of man had the cellu- 

 lose of his food dealt with by bacteria. 



Most people are inclined to shudder when they hear of 

 bacteria in their bodies, but it is only certain kinds of bacteria 

 that pour poisons into the blood and cause disease. Each one of 

 us houses trillions of friendly bacteria in the large intestine. 

 They do us no harm, however, but break up the cellulose (the 

 husks of grain, etc.) and multiply prodigiously in the fetid, fer- 

 menting mass in the intestine. Some physiologists think that 

 we should be better without the large intestine, but, while there 

 is little food absorbed from it, much of the water we take up is 

 absorbed there. In any case, there the structure is, and the wise 

 man takes plenty of cereals, fruit, and green vegetables in his 

 food, to keep it in a state of healthy activity. 



5 

 The Vital Fluid 



Let us return to the nutritive material which has been taken 

 up into the system. The tiny organs on the bowel wall which 

 absorb it pass most of it directly into the blood-vessels which they 



VOL. II 3 



