Mar. x, 1924 
Movement of Water in Irrigated Soils 
683 
Table XXVI. —Elevation and salt content of underground water infield O at the Huntley 
Experiment Farm, Montana a 
Apr. 28 
May 31. 
July 1.. 
Aug. 1. 
Sept. 3. 
Oct. 2 . 
Nov. 3. 
Dec. 4. 
Jan. 3.. 
Feb. 5.. 
Mar. 1.. 
Apr. 3.. 
May 1. 
June 1. 
June 27 
July 25- 
Aug. 22 
Date. 
1922. 
1923. 
Elevation, 
water surface. 
Depth 
to water. 
Salt content. 
2, 966. 4 
IO. 0 
Per cent. 
4* 25 
2, 966. 7 
9 * 7 
4. 20 
2, 967. 6 
8. 8 
4. 17 
2,972. 8 
3- 6 
4 . 17 
2,971.0 
5*4 
4*37 
2, 970. 4 
6. 0 
4. 29 
2, 969. 3 
7 * 1 
4. 28 
2, 968. 9 
7 * 5 
4. 28 
i 
2,968.1 
8*3 
3 * 9 ° 
2,967.7 
8.7 
4. 00 
2,966.7 
9 * 7 
3 * .76 
2, 966. 8 
9. 6 
3 * 90 
2, 966. 0 
10. 4 
3 * 79 
2, 966. 2 
10. 2 
3 * 46 
2, 968. 0 
8.4 
3 * 2 4 
2,970. 9 
5 * 5 
3 * 
2,971.9 
1 
4 * 5 
2. 99 
a The ground surface elevation is 2,976.4 feet above sea level. 
b Determined by electrical conductivity. 
Table XXVII. —Composition of underground water in field O at the Huntley Experi¬ 
ment Farm , Montana , in July , 1923. 
PARTS PER MILLION 
Total solids. 
Ca. 
Mg. 
HCOa. 
Cl I 
Cl. | 
1 
SO. 
Total 
acids. 
37 >° 8 °. 
410 
980 
240 
420 
1 
23.764 
24, 424 
reacting values 
37 > o8 °- : . 
20.5 
80.5 
3-9 
11.8 
I 
1 
494.0 
5 ° 9*7 
PERCENTAGE REACTING VALUES 
37 ? 080 . 
4.0 
I 5 8 
| 0.8. 
2.3 
i 
96.9 
100.0 
o Collected by Hansen and analyzed by Brezeale. 
THE ALKALINE CARBONATES 
In the literature dealing with the problems of alkali soils the soluble 
carbonates occupy the center of the stage. “ Black alkali _ has been the 
bete noir of the irrigation farmer as well as of the investigator. Black 
alkali is usually defined as sodium carbonate while all the other salts in 
irrigated lands are referred to as white alkali. The carbonates of the alkali 
bases, sodium and potassium, are readily soluble in water. The carbonates 
of the earthy bases, calcium and magnesium, are practically insoluble in 
