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TiMEHRI. 



with nitrogen, and that heavier manurings, although 

 probably giving greater returns of canes, will not result 

 in increased profit but probably in loss, such loss being 

 the greater the more unfavourable the climatic condi- 

 tions are for continued growth during the later periods 

 of the crop. As regards the influence of increased 

 nitrogenous manurings upon the composition of the 

 juice, the experiments have shown that the juice yielded 

 by the higher dressings of nitrogen was almost invariably 

 of lower saccharine richness than that yielded by 

 the lower, showing that the canes had not been able 

 to make as complete use of the high dressing during 

 their growth as of the low ones. My experience is 

 that the limit of application of nitrogenous manures 

 so as not to in any way affe6t the saccharine richness 

 of the canes, is from 50 to 60 lbs. of nitrogen per acre, 

 equivalent to from 250 to 300 lbs. of sulphate of ammonia* 

 As regards the form of nitrogen Vvhich the canes 

 made use of most completely, the results of the experi- 

 ments speak strongly. When the experiments were 

 commenced I hoped and expe6ted that we should find, 

 as in the majority of experiments with the gramineaej 

 nitrate of soda a preferable source of nitrogen to sulphate 

 of ammonia, but the opposite proved to be the case. 

 In each year's experiments, including those of 1886, 

 nitrate of soda proved to be far less efficacious than 

 sulphate of ammonia, and this was the more marked 

 where the higher amounts were applied. Doubtless 

 much of this difference was due to the shallowness 

 of the soil at Dodds, and to heavy tropical rains occurring 

 soon after the application of the manure causing great 

 loss of nitrogen by drainage and surface washing, this 



