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and potash which it contains. The relative manuring value 

 of the nitrogen and ash constituents in foods is well shown in 

 Lawes and Gilbert's Table. 1 In box-feeding there should be 

 practically no loss of ash constituents. If urine is lost, much 

 potash will go with it. If the rotted manure is washed by rain, 

 both potash and phosphates will more or less escape. 



When cake manure is applied in moderate quantities to 

 mangels, it will yield a better return and have a higher value 

 than when applied to a cereal crop ; a better return will also 

 probably be found when the manure is applied to turnips, 

 potatoes, and grass land, though in these cases no exact 

 experiments are available. 



We have hitherto spoken of the value of nitrogen in food 

 employed in various ways ; a wholly different question is the 

 value of nitrogen in farmyard manure. In making this 

 manure very considerable losses of nitrogen have taken place, 

 these losses being apparently much larger than have usually 

 been believed. The nitrogen in the manure finally obtained 

 will clearly have a higher value than the one penny per pound 

 at which we have reckoned the food contributing to it. While 

 the experiments at Eothamsted, and elsewhere, provide many 

 examples of the return in crops from the use of known 

 quantities of farmyard manure, it is unfortunate that none 

 of these experiments give any exact information as to the 

 quality and composition of the farmyard manure used. The 

 estimated value of the manure is clearly in many cases too 

 high, very little account having been taken of the serious 

 losses occurring during its preparation. 



None can be more sensible than myself of the insufficient 

 foundation on which many of the estimates I have given you 

 have been based. I have endeavoured to bring before you 

 some of what appear to be the best ascertained facts relating 

 to the practical value of manure residues ; these facts are few, 

 but they have a greater practical value than the estimates 

 and assumptions on which valuations have hitherto been 

 largely based. I trust that, before many years have expired, 

 more exact and extended investigations will have relegated my 

 lecture to the domain of ancient history. 



1 Jour. Roy. Agri. Society, 1897, 698. 



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