THE BAFFLING PROBLEM 



oxidation, that without it a living body ceases to 

 function, though everywhere all about us is oxida- 

 tion without life; it knows the part played by 

 chlorophyll in the vegetable kingdom, and yet how 

 chlorophyll works such magic upon the sun's rays, 

 using the solar energy to fix the carbon of carbonic 

 acid in the air, and thereby storing this energy as 

 it is stored in wood and coal and in much of the 

 food we consume, is a mystery. Chemistry cannot 

 repeat the process in its laboratories. The fungi do 

 not possess this wonderful chlorophyllian power, 

 and hence cannot use the sunbeam to snatch their 

 carbon from the air; they must get it from decom- 

 posed vegetable matter; they feed, as the animals do, 

 upon elements that have gone through the cycle of 

 vegetable life. The secret of vegetable life, then, is 

 in the green substance of the leaf where science is 

 powerless to unlock it. Conjure with the elements 

 as it may, it cannot produce the least speck of living 

 matter. It can by synthesis produce many of the 

 organic compounds, but only from matter that has 

 already been through the organic cycle. It has lately 

 produced rubber, but from other products of vege- 

 table life. 



As soon as the four principal elements, carbon, 

 oxygen, hydrogen, and nitrogen, that make up the 

 living body, have entered the world of living mat- 

 ter, their activities and possible combinations enor- 

 mously increase; they enter into new relations with 

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