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MESSRS. J. B. LA WES AND J. H. GILBERT ON THE RESULTS OF 
were used alone ; whilst, as with the produce, so with the nitrogen, there was an 
increased yield over the second 10 years with the mineral manures used alone. 
Of total mineral constituents about two-and-one-third times as much were taken 
up as either without manure, or with the ammonia-salts alone, and about one-and- 
one-thh'd time as much as when the same mineral manure was used without a mm onia - 
salts. With the mineral manures alone, however, there was a slight increase in the 
amount taken up over the second 10 years ; but when used with the ammonia-salts 
there was a reduction of 18 per cent., or in greater proportion than without manure, 
but in only about half the proportion as when the ammonia-salts were used alone. 
Thus, with the ammonia-salts and the mixed mineral manure together, there was a 
great increase in the produce of hay, and in the amounts of nitrogen and of mineral 
matter taken up, compared either with the result without manure, with the ammonia- 
salts alone, or with the mineral manure alone. But whilst with the mineral manure 
alone there was an increase in all three items of yield over the second compared with 
the first 10 years, there was with the ammonia-salts and mineral manure together a 
reduction in all three, but in much less proportion than when the ammonia-salts were 
used alone. 
In explanation of these great differences in the amounts of produce yielded, and of 
nitrogen and mineral matter taken up, it is essential to take into consideration the 
very different character of the herbage in the several cases. 
Without manure the herbage was very complex, and though diminutive, a relatively 
large proportion of the plants developed stem, showed tendency to seed formation, 
and would be comparatively mature at the time of cutting. The complex herbage 
contained a comparatively large proportion of other than gramineous species, of which 
the Leguminosoe would be nearly twice as rich in nitrogen as the grasses, and the 
miscellaneous species would also be somewhat richer. The result is that without 
manure there was, as already pointed out, an average over the 20 years of nearly 
twice as much nitrogen as would be obtained in a gramineous crop growing separately, 
such as wheat or barley. 
With the mixed mineral manure, including potass, used alone, there was, it will be 
remembered, besides a considerable increase of produce due to gramineous species, 
a proportionally much greater increase of leguminous herbage, and also some increase 
due to miscellaneous species. Under these conditions, there was a considerably 
increased amount of nitrogen taken up without any being supplied in the manure, 
and it was concluded that it was derived from the stores of the soil itself. 
With ammonia-salts alone, on the other hand, there was scarcely a trace of 
leguminous herbage, and very little due to any miscellaneous species, except Rumex 
acetosa. The produce was very characteristically gramineous. In the later years 
nearly one-half consisted of one species, Festuca ovina, and about a quarter of Agrostis 
vulgaris. This almost exclusively, and very simple, gramineous herbage showed, more¬ 
over, very little tendency to form stem and seed, or to mature, but consisted chiefly of 
