4 MICROBES AND TOXINS 



the formation of the protein compounds is dependent on the 

 chlorophyll activity ; without this it would be impossible 

 for them to build up the carbohydrates, and these are 

 indispensable in the employment and elaboration of the 

 nitrogenous elements of the soil, The chlorophyll activity 

 is itself dependent on the sunlight, so that life is one great 

 psean to the sun. 



In the transformation of carbon and nitrogen all the 

 operations are not carried out by microbes, for these latter do 

 not count at all in chlorophyll assimilation nor in animal 

 digestion. But it is the bacteria which keep up the supply of 

 organic matter which forms the source of animal and 

 vegetable life ; it is the bacteria which restore to circulation 

 those elements which were for a moment arrested in the bodies 

 of animals and plants : they restore to life matter which had 

 ceased to live. It is they also which prepare the soil for 

 vegetation and cultivation : they accumulate in the soil the 

 nitrogen which we are to eat in the form of cereals. 



It is they which carry on the impenetrable mystery referred 

 to by Lavoisier. 



They prepare the primary material of life. Their activity 

 is as universal as that of water, as that of light. 



The discoveries of Pasteur have not only revolutionised 

 medicine, they have filled with new life the science and 

 practice of agriculture and husbandry. 



I. — Maturation of the soil and formation of arable land. 



It was not the bacteria which shattered, splintered and 

 powdered the rocks which formed the first crust of the cooling 

 globe. But as soon as in this chaos there appeared water and 

 alkaline phosphates, algae and bacteria could establish 

 themselves and with the help of carbonic acid continue the 

 first formation of soil. 



In those rocks known as '' rotten rock," Miintz found 

 nitrifying microbes : the nitrifying ferment has also attacked 

 the Faulhorn, a mountain of the Bernese Oberland near 



