on Permanent Meadoio Land, 565 



which the other experiments extended. The nitrate too, was 

 sown about a week later than the other manures. The result of 

 this single season's trial with the nitrate was, that a given 

 amount of nitrogen so supplied, did not increase the produce of 

 hay equally with the same amount in the form of ammoniacal 

 salts. Still the influence of artificial nitrogenous supply upon 

 the Grass crop is here again illustrated. 



Nitrate of soda, in amount supplying nitrogen equal to about 

 50 lbs. of ammonia per acre (Plot 6), gave scarcely any increase 

 whatever over the mean unmanured produce of the same season.* 

 Double this amount of nitrate of soda (Plot 7), containing 

 nitrogen equal to the ammoniacal salts of Plot 4, gave about 

 3f cwts. less increase of hay per acre than the equivalent amount 

 of ammoniacal sails. When the smaller amount of nitrate of 

 soda was used in conjunction with the " mixed mineral manure,'* 

 the produce amounted to 1 ton 17| cwts. of hay, or to Hi cwts. 

 more than when the same amount of nitrate was used alone. 

 Lastly, with the larger amount of nitrate of soda ( = in nitrogen 

 to the 400 lbs. of ammoniacal salts), together with the " mixed 

 mineral manure " (Plot 15), there were 2 tons 10| cwts. of produce 

 instead of 1 ton llf cwts. by the same amount of nitrate of soda 

 without the mineral constituents. This increased produce by the 

 nitrate of soda and mineral constituents was, however, consider- 

 ably less than either the average annual yield, or that of the third 

 season taken alone, by an equal amount of nitrogen in ammoniacal 

 salts, with the mineral manure in addition. So far, however, as the 

 action of the manures applied in such full quantity is cumalative 

 from year to year, it will of course to that extent be illegitimate 

 to draw any strict comparison between the produce of one manure 

 in its third season, and that of another in its first season of appli- 

 cation. The character of nitrate of soda as an efficient Grass 

 manure, and as acting, both on this and other crops, by virtue of 

 the nitrogen it contains, is too well established by other experi- 

 ments — indeed by common experience also — to admit of doubt. 

 It remains to be seen, what will be the comparative effects of a 

 given amount of nitrogen supplied in nitrate of soda and in 

 ammoniacal salts respectively, when the trials have been con- 

 tinued over numerous and various seasons. 



Before leaving the results with the nitrate of soda, it should be 

 stated that it had the same effects as the ammoniacal salts, in 

 discouraging the growth of the Leguminous herbage, and in encou- 



* It will be remembered, however, that in this third season the duplicate un- 

 manured plot gave an obviously somewhat excessive produce of hay ; it having 

 given smaller moKJi crops than the other in the preceding se*asons, but more after- 

 feed, and hence the condition of the land on the duplicate plot would be relatively 

 somewhat too high for the third mown crop. 



