THE CAPTURE OF SUNLIGHT 51 



Capture of tlie Energy of SunUgJd 



After the sun's heat Hving matter appears to have captured 

 the sun's hght, which is essential, directly or indirectly, to all 

 living energy higher than that of the most primitive bacteria. 

 The discovery by Lavoisier (i 743-1794) and the development 

 (1804) by de Saussure' of the theory of photosynthesis, namely, 

 that sunshine combining solar heat and light is a perpetual 

 source of living energy, laid the foundations of biochemistry 

 and opened the way for the establishment of the law of the 

 conservation of energy within the living organism. 



Thus arose the first conception of the cycle of the elements 

 continually passing through plants and animals which was so 

 grandly formulated by Cuvier in 181 7:- "La vie est done un 

 tourbillon plus ou moins rapide, plus ou moins complique, 

 dont la direction est constante, et qui entraine toujours des 

 molecules de memes sortes, mais ou les molecules individuelles 

 entrent et d'ou elles sortent continuellement, de maniere que 

 \3i forme du corps vivant lui est plus essentielle que sa matiere.'" 



Chemical Composition of Chlorophyll^ 



Carbon 73.34 



Hydrogen 9.72 



Nitrogen 5-68 



Oxygen 9.54 



Phosphorus 1.38 



Magnesium 0.34 



The green coloring matter of plants is known as chloro- 

 phyll; its chemical composition according to Hoppe-Seyler's 



' De Saussure, N. T., 1804. 



- Cuvier, Baron Georges L. C. F. D., 181 7, p. 13. 



3 Sachs, Julius, 1882, p. 758. 



