EXCHANGE OF IONS 
53 
would show somewhat different results, because the individual varia- 
tion in seedlings introduces an error which is surely of considerable 
magnitude. The general fact is nevertheless clear that mixtures of 
three nitrates are more favorable to absorption than solutions of 
single nitrates or mixtures of two. Our former work (1. c.) on mixtures 
of two salts indicates that if the total concentration of the solutions 
had been greater, there would have been a much greater difference 
between the absorption from single salts and that from the less 
favorable mixtures. However that may be, the contrast between 
this experiment and the next is very great. The fact to be kept in 
mind is that in even the most favorable mixtures of the three nitrates 
Table II. 
Daily Concentration Relations 
5 
6 
7 
8 
9 
10 
II 
12 
13 
14 
1.037 
0.998 
0.918 
0.831 
0.757 
0.735 
0.723 
0.770 
0.900 
0.659 
0.576 
0.533 
0.499 
0.466 
0.464 
O.5II 
0.607 
0.857 
0.937 
0.897 
0.880 
0.848 
0.797 
0.801 
0.837 
0.913 
1.020 
0.712 
0.619 
0.531 
0.444 
0.370 
0.360 
0.401 
0.510 
0.761 
0.653 
0.528 
0.432 
0.358 
0.306 
0.296 
0.322 
0.361 
0.492 
0.824 
0.723 
0.665 
0.629 
0.591 
0.614 
0.708 
0.869 
1. 186 
0.688 
0.571 
0.487 
0.393 
0.300 
0.231 
0.208 
0.249 
0.387 
0.578 
0.517 
0.432 
0.345 
0.263 
0.198 
0.176 
0.198 
0.301 
0.563 
0.441 
0.349 
0.296 
0.254 
0.256 
0.303 
0.380 
0.551 
0.805 
0.728 
0.672 
0.640 
0.607 
0.595 
0.618 
0.661 
0.753 
0.738 
0.642 
0.576 
0.476 
0.406 
0.342 
0.295 
0.262 
0.285 
0.660 
0.551 
0.464 
0.400 
0.349 
0.310 
0.290 
0.298 
0.363 
0.548 
0.430 
0.352 
0.261 
0.186 
0.144 
0.127 
0.187 
0.216 
0.549 
0.441 
0.356 
0.298 
0.243 
0.2II 
0.195 
0.198 
0.267 
0.806 
0.732 
0.683 
0.649 
0.612 
0.610 
0.632 
0.663 
0.736 
0.748 
0.675 
0.640 
0.576 
0.502 
0.445 
0.402 
0.379 
0.403 
0.671 
0.593 
0.517 
0.443 
0.375 
0.328 
0.288 
0.271 
0.312 
0.589 
0.441 
0.344 
0.276 
0.206 
0.160 
0.143 
0.137 
0.190 
0.533 
0.368 
0.278 
0.216 
0.162 
0.132 
0.I2I 
0.133 
0.228 
0.451 
0.550 
0.415 
0.341 
0.292 
0.243 
0.208 
0.199 
0.221 
0.335 
0.571 
0.910 
0.846 
0.828 
0.812 
0.774 
0.759 
0.763 
0.784 
0.832 
0.917 
0.851 
0.793 
0.733 
0.667 
0.600 
0.546 
0.500 
0.471 
0.449 
0.491 
0.691 
0.620 
0.585 
0.544 
0.499 
0.453 
0.399 
0.354 
0.387 
0.514 
0.624 
0.550 
0.491 
0.440 
0.388 
0.346 
0.320 
0.289 
0.294 
0.367 
0.578 
0.476 
0.395 
0.322 
0.255 
0.2 1 1 
0.189 
0,196 
0.247 
0.354 
0.518 
0.427 
0.339 
0.287 
0.218 
0.174 
O.I5I 
0.132 
0.140 
0.227 
0.494 
0.410 
0.359 
0.312 
0.263 
0.224 
0.205 
0.193 
0.227 
0.337 
0.895 
0.851 
0.829 
0.805 
0.765 
0.749 
0.741 
0.740 
0.762 
0.839 
1.003 
0.969 
0.916 
0.868 
0.803 
0.735 
0.705 
0.682 
0.733 
0.852 
0.885 
0.807 
0.738 
0.670 
0.586 
0.514 
0.476 
0.448 
0.453 
0.549 
0.750 
0.653 
0.560 
0.484 
0.401 
0.343 
0.323 
0.331 
0.400 
0.553 
0.699 
0.653 
0.599 
0.528 
0.452 
0.406 
0.379 
0.361 
0.400 
0.534 
0.614 
0.534 
0.464 
0.395 
0.332 
0.305 
0.291 
0.339 
0.456 
0.734 
0.650 
0.590 
0.541 
0.489 
0.468 
0.472 
0.489 
0.547 
0.657 
0.733 
0.665 
0.616 
0.576 
0.525 
0.493 
0.474 
0.464 
0.513 
0.660 
0.920 
0.831 
0.822 
0.807 
0.781 
0.794 
0.805 
0.835 
0.888 
0.978 
