476 
Philippine Journal of Science 
1920 
portion of the solution that lies closely adjacent to the root 
surfaces. These partial concentrations should of course be main- 
tained constant in experiments of this kind, but the large 
Table 3 . — Summary of the experimental series, showing dates, solution type, 
and total molecular concentration {also estimated osmotic value as a 
fraction of an atmosphere of pressure) for each series. 
Series. 
Date 
(1918). 
Total concentration. » 
Beginning. 
Ending. 
3-salt type I. 
4-salt type A. 
4-salt type B. 
Gram- 
molecule 
per liter. 
Atmos- 
phere. 
Gram- 
molecule 
per liter. 
Atmos- 
phere. 
Gram- 
molecule 
per liter. 
Atmos- 
phere. 
11 
0.002 
0.01 
2.... 
March 
21 
April 
11 
1 0. 012 
0.05 
3 
March 
24 
April 
11 
4__._ 
February 
22 
March 
14 
1 
6-„. 
March 
21 
April 
11 
[ 0.0061 
0.23 
6.... 
March 
24 
April 
11 
7.... 
March 
21 
April 
11 
1 0.0123 
0. 46 
8 
March 
24 
April 
11 
9.... 
March 
21 
April 
11 
0. 0245 
0.93 
10 b.. 
March 
11 
April 
6 
0.0002 
0.01 
11 
0. 0012 
0.05 
12 
0.0061 
0. 23 
0. 0123 
14.... 
June 
19 
July 
9 
0.0008 
0.04 
15.... 
May 
24 
June 
14 
} 
0. 0016 
16.-.- 
June 
19 
July 
9 
) 
17— - 
May 
1 
May 
22 
] 
18--.. 
May 
24 
June 
14 

0.0038 
0.20 
19— 
June 
19 
July 
1 
20—. 
June 
19 
July 
g 
0. 0077 
0.40 
21 — 
May 
24 
June 
14 
0.0192 
1. 00 
22— 
May 
1 
May 
22 
0 0384 
2.00 
23-- 
August 
3 
August 
23 
1 
24-- 
September 
9 
September 
29 
1 
0.0008 
0. 04 
25.— 
August 
8 
August 
23 
1 
0. 0016 
0.08 
26— 
September 
9 
September 
29 
1 
27.... 
August 
3 
August 
23 
1 
0.0038 
0.20 
28.... 
September 
September 
29 
1 
* Total fraction of a gram-molecule of all salts per liter, and estimated osmotic value as 
a fraction of an atmosphere of pressure. 
Series 10, 11, 12, and 13 were with wheat, for comparison with the results obtained by 
Shive. 
amounts of solutions needed and the work involved to accom- 
plish this made it seem undesirable to attempt the use of con- 
tinuously renewed solutions in these preliminary studies ; when 
“ Trelease, S. F., and Free, E. E., The effect of renewal of culture 
solutions on the growth of the young wheat plants in water-cultures, Johns 
Hopkins Univ. Cir. (March, 1917) 425 and 426. 
