May 16,1921 
Quality of Irrigation Water 
269 
and the soil was rich in calcium carbonate. In this experiment 300 gm. 
of dry soil were placed in the percolation tube and leached first with 
distilled water, 100 cc. being used for each leaching. After seven leach- 
ings with water, solutions of sodium chlorid were added, each successive 
solution being stronger than the preceding, until at the twentieth leach¬ 
ing a concentration of 5 per cent was reached. For the twenty-fifth 
leaching a solution of 3.7 per cent was used, and the twenty-sixth and 
later teachings were made with pure water. 
Table I shows the concentration of the various salt solutions used, 
the rate of percolation, the concentration of the later percolates as shown 
by the electrolytic bridge, the chlorids in the percolate as determined 
by titration with silver nitrate and calculated as sodium chlorid, 1 the 
alkalinity of the percolate as determinated by titration with N/10 sul¬ 
phuric acid, using butter yellow as an indicator, and the character of 
the percolate with respect to turbidity. 
Table I .—Effect of leaching with sodium-chlorid solution followed by water on the rate 
of percolation and the character of the percolate 
Leach¬ 
ing 
No. 
Leaching solution. 
Percola¬ 
tion rate 
per minute. 
Salts in 
percolate 
(by bridge). 
Chlorids 
as NaCl. 
Acid N/io 
HaSCLfor 
IOO cc. 
percolate. 
Character of 
percolate. 
Cc. 
P. p. m. 
P. p. tn. 
Cc. 
1 
Water. 
I. 2 K 
e8 
I. 80 
Yellowish. 
2 
.do. 
I. 7 ^ 
2 2 
T. AO 
Whitish turbid. 
2 
.do. 
I. KO 
0 
I e 
. 80 
Do. 
0 
4 
.do. 
1.64 
47 
. 66 
Do. 
5 
2- 13 
*r/ 
35 
. 60 
Do. 
6 
.do. 
2 . OO 
27 
. 66 
Do. 
7 
.do. 
l8 
. 66 
Do. 
8 
NaCl p. p. m. 93... 
1. 54 
70 
.66 
Slightly turbid. 
9 
NaCl p. p. m. 210.. 
1. 82 
164 
•32 
Clear. 
10 
NaCl p. p. m. 327.. 
28t 
^26 
Do. 
11 
NaCl p. p. m. 421.. 
1. 67 
375 
•32 
Do. 
12 
NaCl p. p. m. 515.. 
1. 70 
468 
•32 
Do. 
13 
NaCl p. p. m. 795.. 
643 
•34 
Do. 
14 
NaCl p. p. m. 
1. 23 
643 
1. 00 
Do. 
1,028. 
15 
NaCl p. p. m. 
2.03 
I, 286 
.60 
Do. 
1,987. 
16 
NaCl p. p. m. 
1. 89 
2,457 
.40 
Do. 
3,226. 
x 7 
NaCl p. p. m. 
2. 00 
3 , 5 io 
•50 
Do. 
5,150- 
18 
NaCl p. p. m. 
1. 70 
7,030 
.30 
Do. 
10,520. 
19 
NaCl p. p. m. 
1. 67 
15,7 80 
.40 
Do. 
25,000. 
20 
NaCl p. p. m. 
3 2 > 750 
. 60 
Do. 
50,000. 
21 
NaCl p. p. m. 
1.43 
65, 5 2 ° 
1. 20 
Do. 
50,000. 
22 
NaCl p. p. m. 
i- 33 
47 , 9 6 9 
1. 30 
Do. 
50,000. 
23 
NaCl p. p. m. 
1-25 
. 
49.725 
1. 10 
Do. 
50,000. 
1 
1 The clear percolates, particularly those resulting from the use of the strong salt solutions, showed the 
presence of calcium, but the quantity was not determinated. 
