ON THE APPLICATION OF MANURES. 261 



eveiy case have produced better crops than that of 

 the unploughed, instead of doing it in none. Similar 

 results, too, must, have followed in the other cases 

 which I have stated, whereas- 1 have never seen nor 

 heard of their doing it in any one. 



My belief, founded on the facts already stated, is, 

 that all the fertilizing substances of manures are 

 soluble in water, and will remain uninjured them- 

 selves, and useless to plants until the solution be- 

 gins, whether they be deposited on or under the 

 earth's surface. I also believe that this solution is 

 caused by every fall of rain, and is immediately ab- 

 sorbed by the subjacent soil, which absorption re- 

 sults from two causes : first, the principle of gravi- 

 ty ; and, secondly, the stronger attraction of the 

 earth than of the atmosphere for every substance in 

 solution which constitutes the food of plants more- 

 over, that the earth never parts with this food, when 

 thus absorbed, to anything but the plants themselves ; 

 for it is their peculiar aliment, and not that of the 

 atmosphere, whose existence, for aught we know to 

 the contrary, is entirely independent of it, although 

 its agency seems essential to the health and vigour 

 of all plants. If this were not the fact ; if, for ex- 

 ample, the earth did give the best and greatest, por- 

 tion of this food to the atmosphere, or if it escaped 

 from surface-spread manure before gravity and at- 

 traction could impart it to the earth, then the evap- 

 oration which is supposed to be the medium of con- 

 veyance, and which is known to be constantly going 

 on from the soil, would, in process of time, certainly 

 render it barren, even without any cultivation what- 

 ever. Yet neither total nor partial barrenness is 

 ever known to be produced by any other cause than 

 incessant culture without manure. That evapora- 

 tion does take off something from manure while in 

 a moist state, is proved by the offensive smell which 

 constantly exhales from it until it is entirely dry. 

 This smell arises from a gas which is said by some 



