1G2 ACTION OF SOIL ON FOOD OF PLANTS IN MANURE. 



is about 126 tons per acre, equal to about 26^ tons of 

 hay. In four years the increase by the use of gypsum 

 amounted to 15^ tons of green clover. The increase in 

 the four years by the use of the alkalis and phosphate is 

 estimated to amount to 28f tons of green produce.' 



' It is worthy of remark,' continues the report, ' that 

 it was m some of the very same seasons in which these 

 heavy crops of clover were obtained from the garden 

 soil, that we entirely failed to get anything like a mode- 

 rate crop of clover in the experimental field, only a few 

 hundred yards distant.' 



It is, indeed, most worthy of remark, that upon the ex- 

 perimental field the earth was poisoned by the vegetation 

 of the clover, so as to render it incapable of further bear- 

 ing this plant ; while, at the very same time, under hke 

 chmatic conditions, the self-same clover-plant engendered 

 no poison in the rich garden soil. 



A comparative examination of the garden and of the 

 field-soil seems never to have been thought of, since the 

 two agricultural chemists were, as we before remarked, 

 in search of an efiicient manure, not of the cause of the 

 failure of the plant. But though they have not found 

 the smallest shred of a fact which might serve in any way 

 to explain the strange behaviour of the clover-plant upon 

 the two fields, they do not hesitate to present the farmer 

 Avith the following ingenious explanation : — 



' Among plants,' say they, ' there are certain kmds 

 which are pecuharly circumstanced with respect to the 

 nature of their food ; the cereals, among others, feed 

 principally upon inorganic matters, whilst others, the legu- 

 minous plants, e.g. clover, are dependent for luxuriant 

 growth, more or less, upon a supply withm the soil of 

 complex organic compounds.' 



Takmg their stand upon the fact that they have failed 



