Energies of the Organic World 79 



in pools, lagoons, and mud-flats, where hydrogen sulphide 

 (H2S) is generated, the plant according to Winogradsky absorbs 

 this along wdth free oxygen, according to the formula H2S+0 = 

 H2O+S. By oxidation action it sets free the sulphur, which 

 accumulates in its tissues, so as even to color it yellow. Next 

 it is stated that the sulphur combines with carbon dioxide 

 (CO2) and other products absorbed only in minute quantity 

 from the water, to form necessary plant foods, and also the 

 necessary heat of respiratory interchange. Now if the required 

 plant foods, the carbohydrates, amides, and proteids, are as 

 readily elaborated as the above reactions indicate, it should 

 be possible to effect the same result in the chemist's laboratory.^ 

 But even a near approach has hitherto failed. If on the other 

 hand we accept it that the already existing molecules of Beg- 

 giatoa represent ether centers of a constitutive energy greatly 

 more condensed than electricity, this might steadily expend 

 a part of its intra-molecular energy in building up new mole- 

 cules, and in recouping its ovm temporary loss. Thus we get 

 a bridge built, so to speak, between inorganic and organic 

 bodies. 



In the purple bacteria it is found that slight traces of chlor- 

 ophyll exist, somewhat masked by the pink-purple pigment 

 that gives them their name. In contrast, therefore, to Beg- 

 giatoa they make for and luxuriate in the light. But further 

 they hve and flourish amongst concentrated amounts of HoS 

 that would be fatal to other plants. They are able to oxidize 

 the sulphur, by utilizing the oxygen set free in the splitting up 

 of CO2, and this sulphur, instead of accumulating as in Beg- 

 giatoa, is used up directly as a partial source of food and energy. 

 Simultaneously, however, additional material is built up from 

 union of carbon and water. 



We therefore have, in these simplest types, a double mode 

 of formation of the primary food products, which combines the 

 method in Beggiatoa with that seen in green plants. 



In the Schizophycese or Blue-green Algae the sulphur of 

 Beggiatoa is replaced, as a source of energy, by a reddish green 

 or bluish green chlorophyll compound. As in all bright green 

 plants, this is intimately associated with the protoplasm, and 

 as in them we would regard it as a light absorber and trans- 

 former, which starts organic synthesis by the presence, as we 

 aim to show, of biotic energy. Chlorophyll then would stand 

 in relation to the protoplasm, much as does a water-djnamo 



