1920] 
DUGGAR—H-ION CONCENTRATION AND NUTRIENT SOLUTIONS 23 
TABLE X 
(Series 3, Corn) 
SALT greci AND H-ION CONCENTRATION IN RELATION TO edid 
OLUTIONS A, B, AND C; RENEWAL AFTER A TEN-DAY INTERVA 
Gr. wt.| Total | Great- Pa 
Culture Total of dry | est 
No indices |S" Wt! roots | wt. length 
(gms.) (gms.)| (gms.)| (cm.) | Initial [End 1st per.|End 2nd per. 
1 ¡[Ac h/l 13.70| 3.15| 2.080, 22.42 3.4 OL 6.4 
2 ¡Ac h/2 18.13| 3.83| 2.208| 23.77| 3.7 5.4 6.3 
3 |AcO 4.42| 7.75| 3.922| 31.65) 4.8 4.0 5.2 
4 [Ac 9/10 K | 34.82| 9.10) 3.282| 29.64 5.3 5.6 5.3 
5 |Ac4/5 K | 34.12) 7.72) 3.298) 27.17 5.5 5.1 5.3 
6 |Ac3/5K_ | 37.02, 9.70) 3.589) 28.07, 6.0 5.6 5.4 
7 |Ac1/2K_ | 41.80} 11.30) 3.784) 28.76 6.1 5.6 5.4 
8 |Ac 3/10 K | 37.50) 12.56) 3.397) 27.25 6.4 5.8 6.4 
9 [Ach/Al 19.67, 4.34] 2.491} 23.23 3.6 5.2 6.1 
10 |AcAI 32.29| 9.22| 3.389| 25.70 5.3 5.8 5.3 
11 |BeO 28.26| 8.78| 3.366| 24.36 5.9 7.2 5.5 
12 |2BcO 38.04| 7.77| 4.525| 30.22, 5.8 13 5.3 
13 ¡BcK, 43.00| 12.63| 4.172) 31.83 T 8.0 5.8 
14 |BeCa 29.85| 9.20| 3.617| 26.59| 7.6 8.4 7.3 
15 |BeAl 27.801 7.70| 3.271| 27.75 rax 7.0 5.6 
16 |CcO 30.65| 8.40, 2.923| 24.84 4.8 5.6 7.6 
17 |CcNH 14.44, 3.80) 1.994| 23.85 4.3 4.6 5.8 
18 |CeGC 27.50| 6.97| 2.788| 23.94| 6.7 7.6 8.4 
19 |CcGP 32.37| 8.90| 3.145| 23.83 7-1 7.8 8.2 
20 |Cc /1 31.85| 7.20, 3.060| 26.95 5.3 6.2 1.0 
21 [Cc /2 34.50| 9.35, 3.005| 29.65 5.8 6.4 7.4 
22 [Cc /5 38.901 9.25, 3.487| 29.43 6.4 7.0 T 
23 ¡CcAl 25.06| 5.89| 2.699| 24.74 5.4 6.4 T. 
acidity between AcO and Ac h/1, with salt proportions the same. 
Again, to other eultures containing these two grades of phos- 
phates there were added to each culture vessel (and with each 
renewal) 1 gm. of solid aluminium hydroxide of the highest 
purity procurable. The latter are designated AxAl and Ax h/1 
A] respectively. 
In the B group cultures were prepared with the addition of 
solid aluminium hydroxide (BxAl), as above, also with solid 
calcium carbonate BxCa, with the addition of a small amount of 
K,HPO, (BxK,), and the unmodified solution of double strength 
[2(BxO)]. 
