The Story-Book of the Fields 



inexhaustible and always equally abundant, 

 because the breath of animals, corruption and 

 combustion pour into it incessantly as much 

 carbonic gas as all the plants can consume. 

 In order to maintain the fertility of his fields 

 the agriculturist need not trouble himself 

 about carbon. The crops will find in the air 

 the carbonic gas that they need without his 

 intervention. There remains the ash, a mix- 

 ture of several substances, the most important 

 of which we will now consider. 



If we boil a few handfuls of ashes with 

 water in a pot for a short time and then allow 

 the mixture to cool, the ashes will fall to the 

 bottom and the liquid will become clear. We 

 shall find that this liquid has a peculiar smell 

 like that from the wash-tub in the laundry, 

 and also a sharp, almost a burning taste. 

 This smell of the wash-tub and this sharp 

 taste were not present in the water originally, 

 but proceed from the ashes which have given 

 up certain substances to the water. 



It follows from this that in the ashes there 

 are at least two substances of different nature. 

 The most abundant of these does not melt in 

 water, and collects at the bottom in an earthy 

 layer, while the other, which is only a very 

 small portion of the whole, is easily dissolved 



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