DIGESTION.] 



PHYSIOLOGY. 



"3 



17, e). When bile is not wanted, as when we are 

 fasting, it turns off by a side passage from the duct 

 into the gall-bladder (Fig. 17, /), to be stored up 

 there till needed. 



' 49. What are the uses of all these juices and 

 secretions ? To dissolve the food we eat. 



Fig. 17. — The Stomach laid open behind. 



tf, the oesophagus or gullet ; b, one end of the stomach ; rf, the other end 

 joining the intestine ; ^, gall duct \/, the gall-bladder ; gy the pancreatic 

 duct; hy i, the small intestine. 



We eat all manner of dishes, but in all of them that 

 are worth eating we find the same kind of things, 

 which we call food- stuffs. v 



We eat various kinds of meat ; but all meats are 

 made up chiefly of two things : the substance of the 

 muscular fibre, which you have already learnt is a 

 proteid matter containing nitrogen, and the fat which 



I 



