74 REPORTS OF EXPERIMENTS WITH DIFFERENT TOP-DRESSINGS. 



3, 13, \ Each 1 lb. 15 oz. sulphate of ammonia (containing J lb. 



23, 33. J pure ammonia gas). It was sown in a fine powder. 



4, 14, \ Each 1 lb. 9 oz. chloride ammonium sown in powder. 



24, 34. j In this, and the sulphate ammonia, all the nitrogen is 

 contained in the form of ammonia ; and if there is any difference 

 between them in result, it must be owing to the hydrochloric and 

 sulphuric acids which they contain. 



5, 15, 1 Each 1 lb. 2 oz. nitrate ammonia, dissolved for con- 



25, 35. J venience, as the salt was in coarse crystals, in 1| gallon 

 of water, and applied in the same manner as the glue. 



6, 16, 1 Each 2 lbs. 6 J oz. nitrate of lime (also for convenience 



26, 36. J dissolved in water). 



7, 17, )_ Each 2 lbs. 8 oz. nitrate of soda, sown in powder. In 

 27 > 3 ". j the nitrate soda and nitrate of lime all the nitrogen is 



contained in the nitric acid ; but besides this, the base is of some 

 manurial value. 



8, 18, 1 Each 3 lbs. 9 oz. Peruvian guano, sown in powder. 



28, 38. J This quantity is estimated to contain \ lb. ammonia, 

 like all the other dressings. In addition to which, it contains 

 phosphates and other salts in large quantities valuable for their 

 manurial properties, so that this cannot be considered as a fair 

 experiment, the result of which is to be compared with that of 

 other nitrogenous substances not containing other salts. 



9, 19, 1 Each 1 lb. 1| oz. sulphate ammonia, and 1 lb. \\ oz. 



29, 39. J nitrate soda, both applied dry. These quantities of 

 the two salts together contain the same quantity of nitrogen 

 as \ lb. ammonia. This dressing was applied as being the 

 usual one which is given to grass in this neighbourhood, and 

 helps to show whether a mixture of salts may not supply the 

 wants of the grass and clover better than one salt. 



20, 1 Each 1 lb. 9 oz. of chloride ammonium dissolved, and 

 30. J applied similarly to the other solutions. It was applied 

 thus to see, by comparison with the chloride ammonium applied 

 dry, if there was any difference in result when in solution and 

 in powder. This was to make sure that those salts which were 

 put on in solution had no unfair advantage over the others that 

 were not. There was heavy rain directly after the dressings 

 were all sown, thus giving those salts which are not deliquescent 

 a comparative advantage, as it is in very dry seasons that 

 deliquescent salts can be sown with such great advantage over 

 non-deliquescent ones. 



The edges and points of the leaves of the grass and clover on 

 some of the plots seemed scorched by the dressings, but especially 

 those on which the salts had been put in solution. The plots on 

 which the sulphate ammonia, chloride ammonium, and the nitrate 

 soda with sulphate ammonia were sown dry, were very slight]}- 

 scorched. The plots on which the nitrate ammonia, nitrate of 



