LUTHER BURBANK 



But while he makes his analysis and deter- 

 mines the proportions of the component elements, 

 he is careful to assure us that these elements are 

 doubtless associated in very complex combina- 

 tions of which his analysis gives him only a vague 

 inkling. 



If we glance at the formula by which the 

 chemist represents a molecule of starch — C^ H^° O^ 

 — the thought at once suggests itself that this seems 

 to be a union of six atoms of carbon with five 

 molecules of water; for of course we are all 

 familiar with the formula H^O as representing 

 water, however little we may know of the other 

 niceties of chemistry. 



And in point of fact, this is about the way in 

 which the chemist regards the matter. 



Starch is a compound of water and carbon. 

 The plant secures the water from the soil and the 

 carbon from the atmosphere, where it exists in 

 the form of carbonic acid gas, which is given out 

 constantly from the lungs of every living animal. 



With these simple and universally present 

 materials, then, the wonderful chemist of the 

 plant laboratory builds up the intricate sub- 

 stances that we term starch. 



This substance is stored away in the plant 

 cells, not for the moment available for the purpose 

 of nutrition, but constituting a reserve store of 



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