May si, 1917 Solubility of Certain Inorganic Soil Constituents 
265 
solvent action than did the same quantities of barley or manure. Barley 
and manure in the same amounts had about equal effect in increasing 
the conductivity of the soils to which they were added. 
Table XII.— Effect of the addition of organic matter and inorganic minerals on the 
specific conductivity of sandy loam soil kept moist in the greenhouse for six months a 
Amount and kind of organic matter added. 
Inorganic minerals. 
None. 
Manure. 
Barley. 
Alfalfa. 
1 per 
cent. 
3 per 
cent. 
1 per 
cent. 
3 per 
cent. 
1 per 
cent. 
3 per 
cent. 
None... 
48 
48 
55 
165 
73 
68 
93 
IOO 
US 
207 
143 
60 
IOO 
125 
118 
163 
125 
123 
IS© 
203 
156 
183 
210 
i per cent of calcium carbonate. 
3 per cent of calcium carbonate. 
0.2 per cent of sodium nitrate. 
3 per cent of calcium sulphate. 
a Conductivity figures have been multiplied by 10 5 . 
Table XIII.— Effect of the addition of organic matter and inorganic minerals on the 
specific conductivity of clay-loam soil kept moist in the greenhouse for six months a 
Amount and kind of organic matter added. 
Inorganic minerals. 
None. 
Manure. 
Barley. 
Alfalfa. 
1 per 
cent. 
3 per 
cent. 
1 per 
cent. 
3 Per 
cent. 
1 per 
cent. 
3 Per 
cent. 
None. 
83 
75 
88 
185 
120 
88 
143 
155 
113 
223 
135 
US 
155 
135 
138 
215 
175 
165 
2$0 
230 
238 
325 
288 
1 per cent of calcium carbonate. 
3 per cent of calcium carbonate. 
0.2 per cent of sodium nitrate. 
3 per cent of calcium sulphate. 
a Conductivity figures have been multiplied by io 6 . 
The addition of calcium carbonate to the heavy soil treated with 
organic matter caused a slight decrease in the amount of soluble salts 
liberated as compared with the effect of the organic matter alone. In 
the light soil treated with organic matter the addition of lime increased 
slightly the amount of soluble salts. On the whole, however, the presence 
of calcium carbonate did not greatly modify the formation of soluble 
salts in the soil. 
When gypsum was added to the soil with the organic matter, the 
amount of soluble salts was increased beyond the increase produced when 
the same amount of calcium carbonate was added. This, however, is 
chiefly due to the greater solubility of gypsum. The solubility of gypsum 
is about 2 parts in 1,000, while that of calcium carbonate is much less. 
This is brought out also in Tables XII and XIII, which show that when 3 
