1380 
MESSRS. J. B. LAWES, J. H. GILBERT, ARB M. T. MASTERS, 
of the results obtained on plot 10 with those on plot 9, those on the latter having 
been already separately considered. 
During the first six years of the experiments, plots 9 and 10 each received, annually, 
the same amount of ammonia-salts (400 lbs. per acre), the same amount of superphos¬ 
phate of lime (as on 4-2), and the same amount of the sulphates of potass, soda, and 
magnesia. The only difference between the manuring of the two plots was that, 
during those first six years (and the seventh), plot 10 received in addition to the 
manures mentioned a quantity of sawdust, which was, however, without effect. After 
the six years, the two plots continued to receive the same manure with the one impor¬ 
tant exception that the potass-salt was now excluded from the mixture applied to 
plot 10, and the quantity of the soda-salt was increased. 
Referring to Part I., p. 345, for a fuller account of the facts, it may be briefly stated 
that, during the first six years, plot 10 had received about 900 lbs. of potass per acre, 
which calculation showed was considerably in excess of that removed in the crops. 
There was, therefore (if there were no loss by drainage, and there would certainly be 
but little, if any), an annually accumulating residue of potass. At any rate the result 
was that, compared with plot 9, there was but little falling off in the amount of total 
produce grown during the first five or six years after the cessation of the application 
of potass; and practically the same amount of nitrogen was taken up as on plot 9 with 
the continued supply of potass. Yet the amount of potass taken up declined even in 
the first year of the cessation; though it continued much in excess of that taken up 
on plot 4-2, where none had been supplied. The evidence was that the residue of 
the potass previously applied was not without effect; but the effects both as to 
amount of produce, and the botanical and chemical characters of the herbage, dimi¬ 
nished considerably in the later years. The following Table (LXXVIII., pp. 1382-3) 
gives the botanical details in the same form as usual, and, in addition, the amount 
of actual yield of each species on plot 10, where the application of potass was dis¬ 
continued, compared with that on plot 9, where the potass was continuously applied. 
There were, on the average of the four separation-years, two fewer grasses, two fewer 
Leguminosse, and 18 fewer Miscellanese, or 22 fewer total species in the samples from 
plot 10 with the discontinued supply of potass, than in those from the unmanured 
plot 3. The average number of species was 27, with a tendency to reduction; the 
numbers in the four years being 31, 27, 23, 28. It may here be mentioned that the 
first year of separation (1862) was the first year of the exclusion of the potass from 
the manure. There was even, on the average, a tendency to fewer species than on 
plot 9. 
The percentage of total Graminese in the mixed herbage was not materially different 
on the two plots ; but it was, upon the whole, higher on plot 10 with the smaller 
potass supply. Leguminosae were in quite insignificant proportion on both plots ; but 
in less without, than with, the continued supply of potass. On both, with general 
