56 Influence on the Production of Mutton 



and (b) time of application, is possible. The dissolved bones, 

 of course, contain nitrogen, which is absent from the other 

 two manures, and so on Plot 9 nitrogen was added to the 

 superphosphate as sulphate of ammonia, the amount of 

 nitrogen given to Plot 9 being in nine years (eight at 

 Cransley) twice as great as that furnished by the dissolved 

 bones in two dressings. 



It may be said at once that dissolved bones have done 

 badty — both quantitatively and economically. This result 

 is no doubt due not so much to the poor action of their 

 phosphate, as to the fact that they supply nitrogen. But 

 bone nitrogen is not so energetic a substance as the nitrogen 

 of sulphate of ammonia, and so the position of Plot 10 is not 

 such a bad one as Plot 9. The mutton yielded by two doses of 

 5 cwt. each of basic slag has been much larger at Cockle Park 

 and Sevington than that yielded by two doses of 6 cwt. each 

 of dissolved bones. At Cransley, however, the dissolved 

 bones have produced more live-weight yield than the slag, 

 the aggregate increases over the unmanured plot in eight 

 years being respectively 257 lbs. and 301 lbs. 



When the cost of the two manures is taken into account 

 the bad position of dissolved bones is made much worse. 

 Thus at Cockle Park a nett gain of £6 3s. 6d. from the use 

 of two 5 cwt. doses of slag compares with a nett gain of only 

 £3 12s. 3d. from the use of two 6 cwt. doses of dissolved 

 bones. At Sevington a nett gain of £3 16s. 3d. from slag has 

 to compare with one of only 19s. 6d. from the use of dissolved 

 bones. Even at Cransley, where the dissolved bones have' 

 done comparatively well, they show a nett gain in eight years 

 of only 9s. 3d. per acre, as contrasted with 39s. 3d. in the 

 case of basic slag (Plot 4). 



Similarly the dissolved bones may be compared with a 

 corresponding quantity of superphosphate given to Plot 5. 

 At Cockle Park the gain from the former is £3 12s. 3d., from 

 the latter it is £4 gs. gd., while at Sevington the correspond- 

 ing figures are 19s. 6d. and £3 2s. At Cransley this com- 

 parison cannot be made for reasons already given. 



Dissolved bones, however, have always left a better profit 

 than the combination of superphosphate and sulphate of 

 ammonia. 



