PRODUCTIVE GARDENING 91 



that composed the water molecules and the atoms 

 of carbon, but they are so marvelously put to- 

 gether that they no longer constitute the liquid 

 water or the gas in which the carbon was im- 

 ported. They now constitute an altogether new 

 substance which is termed sugar. 



Thus only three elements are dealt with and 

 these very familiar ones. It would seem as if 

 almost any chemist should be able to manage a 

 simple combination like that. But in point of 

 fact no human chemist knows how to manage 

 it. There are forces to be invoked in effecting 

 that combination of which no chemist has any 

 knowledge. 



Only the chlorophyll grains in the plant leaf 

 have learned the secret, and up to the present 

 they have kept their secret well. 



There are other feats of atom juggling per- 

 formed with the new compound that are wonder- 

 ful enough. For example, the sugary compound 

 is ordinarily transformed, in part at least, into 

 granules of starch to be stored away for safe 

 keeping. And this transformation implies a bit 

 °f J u gg nn g that is by no means easy. But after 

 all it is only the changing of one organic com- 

 pound into another, and the human chemist can 

 do some extraordinary feats in that line. The 

 really wonderful work done in the leaf labora- 



