THE SPKCTAI. IT.KTII.IZERS OF THE FARM. 435 



and utilise any fresh supply of the least abundant, and tJicrefore most 

 important, of the essential ash ingredients. 



The effect of superphosphate upon the root crop is certainly remarkable. 

 In many districts 300 Ibs per acre is found a sufficient application. This 

 will represent 30 Ibs. of phosphorous pentoxide, if the manure contain 20 

 per cent, of soluble or monocalcic phosphates. But, supposing the turnip 

 crop yields 20 tons per acre, it will have removed 40 Ibs. of this ingredient, 

 so that it will have not only used all that was contained in the superphos- 

 phate, but drawn upon the natural resources of the soil to the extent of 10 

 Ibs. This can only be accounted for by the increased energy conferred 

 upon the plant, in the early stages of its growth, by the superphosphate, 

 which gives it the power to thrive and send its roots in search of the 

 mineral constituents native to the soil. 



Although superphosphate is the best manure for turnips, it occasionally 

 happens that it produces but little effect. The cases in which disap- 

 pointments'occur have been thus classified by Dr. Voelcker : 



1. If the phosphates are washed out with heavy rain or undergo changes 

 which render them ineffective. 



J. If the soil contains a sufficient supply of phosphates, when an addi- 

 tional supply can be of no avail. 



3. If the soil is deficient in potash, or other essential ash ingredients, 

 in which case phosphates alone could not produce a result, 



LIME. 



Linif has alivady been noticed as a constituent of all fertile soils, and 

 an ingredient of all cultivated plants. The high proportion in which it 

 occurs in the ash of many plants is sufficient to account for its value as a 

 inanmv, while its mechanical and chemical effects upon the soil enhance 

 its agricultural value. The following plants yield a preponderating quan- 

 of lime in their ash, and have therefore been classed as "Jimo plan 



PERCENTAGE or Lnn; IN TIM: ABB 01 I.KI us < YI.TIVATKI. I'i | 



'cs (stem and leaves) 40.2 per cent. 

 Tobacco. 87.44 " 



xO " 

 Red clover.. ,84.0 " 



White clover 2 per cent. 



M 





 Vetc! 



li-monstrati'd that linif is absolutely MC(VSS:I 

 iM-nt of all plants and tin- fcbOYQ li^t shows how larp 

 riatr.l l.y many l.-^uininous and other OTO 



