CHAPTER XX 



OUR WONDERFUL RIVER OF LIFE AND MARVELOUS 

 TELEGRAPH SYSTEM THE BLOOD AND THE NERVES 



WE have learned how to aid Jack's House in build- 

 ing and repairing itself, and why we should always 

 keep it clean and wholesome. Now in what ways 

 may this wonderful house be protected from the vari- 

 ous hurts and diseases that are likely to come? As 

 a first step toward an understanding of this important 

 question, let us get better acquainted with our wonder- 

 ful river of life. 



What is our wonderful river of life? The blood, 

 of course, because it carries building material and 

 oxygen to every part of the body, and takes away 

 carbonic acid gas and other poisons that would destroy 

 life. If our only way of getting food were from the 

 delivery wagon that brings it to the door, the amount 

 we could have at our daily meals would depend upon 

 what this food vehicle brought, and how regularly 

 it came. 



In a similar way, the amount of building material 

 the various parts of our bodies receive, depends entirely 

 upon how freely and regularly this wonderful red river 



