88 
The Colorado Experiment Station. 
Sample A 
gave 
Percent total nitrogen 
at the end of 27 days. 
0.11688 
Milligrams gained 
per 100 grams 
soil in 27 days. 
0.11688 
0.11963 
Average 0.11779 
10.54 
Sample B 
gave 
0.11550 
0.11688 
0.11825 
Average 0.11688 
9.63 
Sample C 
gave 
0.11413 
0.11413 
0.11413 
Average 0.11413 
6.88 
Sample D 
gave 
0.11550 
0.11413 
0.11550 
Average 0.11504 
7.79 
Sample E 
gave 
0.11275 
0.11275 
0.11413 
Average 0.11321 
5.99 
Sample F 
gave 
0.11275 
0.11130 
Lost 
Average 0.11207 
4.82 
lie fixation obtained and given in Bulletin icc, p. 46 h 
gn en for each 100 c. c. of the culture medium. In order to make’the 
nfr iT eaS ‘ 7 COm ? ara h e 'I e have 8' iven these results in milligrams 
f n °, f a 'V s of , S01 ; T h e r 8011 experimented with was simply 
a &ood, arable soil collected from the College farm at or near a 
point where I had observed the development of brown patches It 
is not one of the soils in which we have observed excessive quan- 
tities of nitrates but even here the nitric nitrogen amounts to 3 27 
percent of the total. The quantities fixed in 20 and 30 days in 
a manmte solution inoculated with an infusion of 10 grants of sod 
aie exhibited m the following table along with the fixation ac¬ 
complished in these samples of soil in 27 days. The inoculation of 
the two samples seems to have made no difference whatsoever. 
NITROGEN FIXED 
Sample 1. 
Sample 2. 
Sample 3. 
Sample 4. 
Sample 5. 
Sample 6. 
Sample 7. 
Sample 8. 
Sample 9. 
Milligrams in 100 cc. 
in 20 days 
Man n i te-Solu tion 
in 30 days 
Sample 
. . 0.00000 
1.05075 
A 
. . 1.19085 
0.56040 
B 
. . 3.08220 
3.43245 
c 
. . 6.16440 
12.46890 
D 
. . 0.84060 
3.08220 
E 
. . 0.77055 
3.57265 
F 
. 3.50250 
3.01215 
. 2.38170 
2.87205 
. 13.02930 
10.15725 
In 100 grams of 
soil in 27 days 
10.54000 
9.63000 
6.88000 
7.79000 
5.99000 
4.82000 
All of the ordinary analytical precautions were taken and 
the mtiogen obtained in the blank test, also run in triplicate, has 
made T o Ctet ' ' EaCh ? f H 16 seventeen separate determinations 
ten these six samples show a decided increase in the amount 
