44 BOARD OF AGRICULTURE. 



Then another thing. The free potash in these ashes is not 

 only set free for the plant, but the ashes affect the particles 

 of soil, and favor its decomposition, and therefore they not 

 only give to the plants what they themselves possess, but they 

 really favor the formation of more ashes in the soil. 



Now, if we burn a plant, we shall find, ordinarily, that we 

 obtain from it just about a given quantity of ash ; not exactly, 

 but there is a certain quantity which every plant must have, or 

 it will not grow. Every man here, I suppose knows that all 

 our plants take a great deal of their food from the air. They 

 do not take as much as Liebig and others used to teach that 

 they did, — .1 have found that out ; they take a great deal of 

 their carbon from the soil ; there is no doubt about that. But 

 they do feed largely from the air, especially our large-leaved 

 plants, and it is absolutely impossible for them to do it, unless 

 they can obtain from the soil just the amount of mineral ma- 

 nure which they need, because they must have, for every pound 

 of wood they make, and for every single seed they make, a 

 given amount of that mineral manure. If they cannot have 

 that, they will not feed upon the gases of the air. They are 

 just in the condition of a sick man, or a man with no appetite, 

 who is brought to a table where there is an abundance of food ; 

 he cannot eat. There is the table and the food upon it, but the 

 plants have no appetite ; the gases pass by the leaves, and 

 they cannot take them in. Now, put your aslies upon the soil 

 and see that they have the mineral manure tliey need, and they 

 are like a man with an appetite ; he will eat anything ; he will 

 clear the table. Let the air come in contact with those leaves, 

 the thousand mouths are open, and they take it in. Do you not 

 see that by putting on mineral manures in this way, you are 

 robbing the air, or taking out what nature put there for the 

 plant to use ? Here are two men, with fields side by side, in 

 equally good condition. One man keeps his soil well supplied 

 with ashes, as my friend Mr. Foote does, and his plants flourish, 

 because they are able to take in the gases from the air. The 

 other man has just as much air, but it has gone by his plants 

 without giving them any nourishment, because he has not sup- 

 plied his soil with mineral manures, and they could not take it 

 in. That is the way. Pump the air. It is forty-five miles 



