The: Fixation oe Nitrogen. 27 
ANALYSES 
XXXI 
XXXII 
Mechanical 
Drain 
Analysis 
Water 
laboratory 
Dabratory 
No. 1067 
No. 1201 
Percent 
Percent 
Above 1.0 mm. dia. . . . 
. . 0.708 
1.0 mm.-0-5 mm. 
.. 1.222 
Calcic sulfate . 
. 21.380 
0.5 mm.-0.25 mm. 
.. 9.851 
Magnesic sulfate . . . 
. 25.249 
0.25 mm.-0.05 mm. 
.. 47.582 
Potassic sulfate .... 
. 0.695 
0.05 mm.-0.01 mm. 
.. 21.021 
Sodic sulfate . 
. 5.119 
0.01 mm.-Clay . . . 
. . 8.419 
Sodic chlorid . 
. 42.874 
Clay, by diff. . . . 
. . 11.197 
Sodic carbonate .... 
. 4.683 
100.000 
100.000 
p. p. m. 
Total solids. 8489.00000 
Ammonia . 0.01800 
Nitrogen as nitrites... 0.00003 
Nitrogen as nitrates... 0.10000 
The two pieces of land discussed at this time differ only in 
this, that one of them has been drained for four years and the 
other is not artificially drained at all. We observe that the soil 
consists of 47 percent of fine and very fine sand, further that 
there is 21 percent of silt and a fair amount of clay. The samples 
1067 and 1076 are alike in location so that they are perfectly com¬ 
parable in every respect except that the land represented by No. 
1076 has been drained for four years; some of the drains having 
been put in recently, others of them at earlier dates. The samples 
are both surface samples, that from the undrained land contains 
8.165 an d the drained land 9.882 percent of water-soluble salts 
which in both cases consist of sulfates, chlorids and nitrates. The 
amounts of nitrates contained in the samples give us for No. 1067, 
2,072 pounds calculated for the top two inches, while No. 1076 
gives us 2,223 pounds calculated for a like depth, or calculated for 
the acre-foot of soil, we have 12,432 and 13,336 pounds respectively. 
The drain water was collected from an east and west drain 
crossing the northern end, while the sample of soil, No. 1076, was 
collected from the southeastern corner of this land. It may be 
further stated that there are two other east and west drains between 
the drain from which the water sample was taken and the point 
where we took the soil sample and in addition to this there is a 
north and south drain running within a few feet east of this latter 
point which is itself not more than fifty feet north of the river 
bank. 
I may also add that the soil on top of and along the side of 
this north and south drain is in the same condition as the sample 
actually taken. 
The object in stating these details is evident, i. e., to show 
that these conditions are independent of the seepage question and 
