40 
C0I.0RAD0 Experiment Station 
These determinations were made in triplicate and some of 
them checked by repeated determinations. One of these sam- 
ples shows a decided increase in the total nitrogen, 229 p.p.m. ; 
three of them show small increases, 4.13 and 20 p.p.m. respec- 
tively, and one of them shows an actual regression. in the am<)unt 
of total nitrogen present. Sample 1 shows an increase of 105 
p.p.m. in the total nitrogen in 30 days, but in the next ten days 
it seems to have lost rapidly. Sample 4 shows a gain of 225 
p.X).m. in 30 days and maintains it during the next 10 days. All 
of the samples show a decided increase in the amount of nitric 
nitrogen present for the 30-day period, but some of them show 
a falling off for the subsequent 10-day period- The amounts of 
total and nitric nitrogen in the land just outside of, and at the 
edge of the area, differ very markedly, and the ratio of the nitric 
nitrogen to the total increases from about 20 percent., which is 
very high, to more than 50 percent., and in only one instance 
has this ratio decreased during the incubation. 
We were not satisfied with these samples, and besides we 
encountered unexpected difficulties in these determinations; 
therefore, we took a second series of samples. The two series 
of samples differ in important respects. The first series was 
taken in March and the second in September. It was impossible 
to sample the same section of the area for the second series; 
besides the area had increased very materially during this in- 
terval. It was practically a new part of the area that we liad 
to sample for the second series, and we increased the number of 
samples to 10 instead of 5. 
We first took 6 samples as nearly in a straight line as we 
could, from north to south as was previously done, but a pre- 
liminary test of these samples showed that there was an ex- 
cessive quantity of nitric nitrogen in our northern-most sample, 
a condition that we suspected from the appearance of the soil 
in the field. In order to get beyond the affected area, we sub- 
sequently took two samples in an east and west line, beginning 
next to the bad area; but a quantitative test showed that our j 
western-most sample, taken well up on the hill, contained more j 
nitric nitrogen than an ordinary soil contains, the determination ! 
showing 129.0 p.p.m. It, therefore, became necessary to take | 
further samples to avoid, if possible, initial, excessive quan- 
tities of nitric nitrogen. We accordingly took two other sam- 
ples on a northward extension of our north and south line. This | 
land had been in crops, oats and com, during the season, but 
these had been cut before our samples were taken. The appear- 
ance of the soil, the stui)ble and the statement of the lessee 
