i9 
Nitrogen Fixation 
ANALYSIS XVIII 
V ATER SOLUBLE FROM SURFACE SOIL. Orchard No. 4. 
Per Cent. 
Calcic Sulfate . 18.986 
Magnesic Sufate . 29.771 
Potassic Sulfate . 1.3 87 
Sodic Sulfate . 39.914 
Sodic Chlorid . 1.474 
Sodic Nitrate . 8.173 
Silicic Acid . 0.295 
100.000 
The nitrates make up 0.673 P er cent of the air dried mass. The 
results of this analysis were what I expected after I had examined 
the conditions in the orchard. 
The next sample is our Laboratory No. 680, and is not from 
an orchard but from an oat field. The owner had previously 
written to me concerning this land. I could not go to inspect it 
at the time but in February, 1908, I was near this place and went 
to see it. The chief trouble was seepage, but above the seeped area 
were other conditions, the surface of the ground was puffed up 
and mealy. I took a sample of the surface soil to a depth of two 
inches, water soluble equalled 5.42 per cent. I was compelled to 
dry the residue obtained on evaporating the aqueous extract to 
dryness at 140° in order to pulverize it; it puffed up, intumesced, 
and possibly suffered incipient decomposition. 
ANALYSIS XIX. 
WATER SOLUBLE PORTION. Laboratory No. 680. 
Calcic Sulfate . 
Calcic Nitrate . 
Magnesic Nitrate . 
Potassic Nitrate . 
Sodic Nitrate . 
Sodic Chlorid . 
Iron and Aluminic Oxids . 
Silicic Acid . 
Loss (water, organic matter, etc.) . 
100.000 
The nitrates in this surface sample equalled 2.722 per cent 
of the air dried soil; this is a trifle over 50 per cent of the total 
soluble salts. It may interest someone to learn that I visited this 
place in the early spring of 1909 and could see no signs of any 
trouble whatsoever beyond the fact that a portion of the field was 
undoubtedly seeped. I visited it again later and the present owner 
who is a stranger to me, was cultivating it preparatory to planting 
it to beets and there was nothing suspicious, even to one acquainted 
with the facts, except the seepage. I visited it again when the 
beets were almost ready to harvest. There were great bare spots 
Per Cent. 
9.919 
. 10.053 
. 17.290 
1.159 
. 21.719 
. 38.179 
0.129 
0.093 
1.459 
