HINDRANCES AND HELPS. 231 



direction its stimulating qualities are supposed to 

 work, he does not inform us. 



About the year 1840, I think, Dr. Dana, of Low 

 ell, published a bouncing little book called a Muck 

 Manual, in which he affirmed very stoutly that gyp 

 sum was quietly decomposed by the roots of the 

 plants, when its sulphuric acid flew off at the silicates, 

 and worried them into soluble shape ; and its lime, 

 on the other side, flew off at the geine, pounding 

 that into a good relish ; in short, he made out so charm 

 ing a little theory, so vivacious in its action, so 

 appetizing to turnips, and so authoritatively stated, 

 that we farmers must needs accept it at a glance, and 

 take off our hats, with&quot; That s it,&quot; &quot; I thought so,&quot; 

 &quot; The very thing.&quot; 



But straight upon this, like a thunder-clap, comes 

 Liebig,* who declares, in his authoritative way, that 

 the value of gypsum &quot; is due to its faculty of fixing 

 the small quantity of carbonate of ammonia, brought 

 down by the rain and the dew ; &quot; at this, we farmers 

 put on our hats again, and waited for the rain. 



Some two or three years after, M. Boussingault, 

 who had gone through the South- American wars 

 under Bolivar, and studied agriculture at Quito, as 

 well as on his own country-estate of Bechelbron, 



* His first book appeared in America, if I am not mistaken, 

 in 1841. 



