Liquid Manure. 17 



absorbed from liquid manure, and retained in a soil which is 

 peculiarly deficient in lime. Experience has shown, moreover, 

 that sandy soil is more benefited by lime and calcareous mixtures 

 than by any other description of manure. 



6. On comparing the amount of potash contained in the liquid 

 after filtration through this sandy soil, with the quantity of pot- 

 ash found in the liquid manure after contact with the two preceding 

 soils, a marked difference will be observed. Indeed, the propor- 

 tion of potash taken up by the sandy soil is quite inconsiderable. 

 We have in this result an indication that soils which do not 

 manifest a high power of absorbing ammonia, likewise have not 

 much effect upon soluble compounds of potash. 



7. Still smaller is the power of this soil to absorb soda-salts 

 and sulphuric acid. As regards the compounds of soda, more 

 especially chloride of sodium, the results obtained here agree 

 with the rest. In all the experiments which I have hitherto 

 made, either with highly complex fertilizing mixtures, or with 

 simple salts of soda, I find that soda generally passes through the 

 soil unabsorbed. 



8. Again, it may be noticed, that we have here an instance of 

 phosphoric acid becoming absorbed from its soluble combina- 

 tions by a purely sandy soil, in which lime is almost altogether 

 absent. At the same time it will be seen that phosphoric acid is 

 not so completely removed by such a soil, as by stiffer and more 

 calcareous soils. 



On the whole, these experiments afford a ready explanation of 

 the fact that the effects of manure on proverbially hungry soils 

 are very transient. 



They suggest, likewise, that the observed failure of super- 

 phosphate as a turnip-manure on such land may be due in some 

 measure to the facility with which soluble phosphates are washed 

 out of the soil. 



The fourth experiment with the same liquid manure was tried 

 on a soil of moderately retentive and naturally very fertile pro- 

 perties. 



The mechanical analysis of this soil and its subsoil gave : 



100-00 100-00 



Submitted to detailed chemical analysis, the soil and subsoil 

 were found to contain in 100 parts : 



