The application were given early in May. The dung, super- 

 phosphate and sulphate of potash were given in all cases alike. 



During the period of growth the plot that received 6 cwt. of 

 magnesia per acre, looked decidedly inferior to the one that had 

 had 3 cwt. 



In every case the produce of the plots to which magnesia had 

 been given in any form fell below that of the " standard " dress- 

 ing only. 



This experiment does not seem to bear out the conclusions 

 obtained at the farm in 1908 nor those arrived at in Scotland. 



The matter requires further enquiry and will be followed up. 



XXI. 



Special fertilisers. - - Nitrates. Ammonium Salts. Lime-cyana- 

 mide. -- Artificial fixation of free nitrogen. - Phosphatic 

 fertilisers. Bone meal and bone ashes. Mineral phosphates. 

 Superphosphates. Basic slag. etc. Potassic manures. 

 Stassfurt salts. Wood ashes. - - Other substances used in 

 fertilising. 



How to use Nitrate of Soda, with a preface by BERNARD DYER. 

 -Notice in Nature, Vol. 84, July i4th, 1910, p. 50. 



Summaries are given of various field trials with sodium nitrate. 



Application of Sulphate of Ammonia on light soils. (Mark 

 Lane Express, 101, 1909, No. 4072, p. 403). Exper. Stat. Rec., 

 Febr. 1910. Washington. 



Reference is made to experiments in which sulphate of am- 

 monia was applied (i) entirely in autumn, (2) one fourth in autumn 

 and three-fourths in spring, (3) all in spring in one application, and 

 (4) in spring in two equal applications, the first just when growth 

 had started and the second 3 weeks later. The crop used was rye, 

 and the experiments extended over 2 years. The soil was well 

 supplied with potash and phosphoric acid. 



