18 
Bulletin 72. 
removed by drainage even though we were unable to detect the 
flow. 
CHLORIN IN THE GROUND WATER. 
§ 55. The amount of chlorin in the ground water was not at 
any time extremely high. The maximum for 1897 was 0.2400 
parts per thousand, unless we include one abnormal result ob¬ 
tained immediately after irrigating the plot, in which case we have 
0.3429 parts per thousand; this result stands alone for 1897. 
The same well, however, in 1898 showed two such variations 
reaching 0.3143 parts per thousand after an irrigation, and 0.5286 
parts on May 16th. The month had been wetter than usual, 2.9 
inches of rain having fallen up to this date. With these excep¬ 
tions this well was not so high in chlorin as two of the other 
three. 
§ 56. The ratio of the chlorin to the total solids in the water 
ranged from 1:18 to 1:25 for well A from May, 1897, till May 1, 
1898; for well B it ranged from 1:15 to 1:19 ; for well C from 1:18 
to 1:22; and for well D from 1:16 to 1:22. In other words the 
salt, NaCl, found in the water did not, at any time during the year, 
amount to quite 1-9 of the total matter held in solution by the water 
and fell as low, in round numbers, as 1-16 of the total solids. In 
1898 the ratio of the chlorin to the total solids for the respec¬ 
tive wells varied as follows: for A, from 1:13 to 1:21; for B, 
from 1:14 to 1:16; for C, from 1:11 to 1:27 ; and for D, from 1:18 
to 1:33. The largest amount of salt, NaCl, present equalled 1-7 
and the smallest 1-20, or from 14.3 per cent, down to 5.0 per cent, 
of the total solids present. The latter part of the season - of 1898 
was quite dry and the water table fell so that some of the wells 
went dry. The total solids fell with the water table and so did 
the chlorin, but not proportionately with the total solids ; the latter 
fell from 4.1857 parts per thousand on May 23 to 2.3429 parts 
on November 7, and the former fell from 0.32400 parts to 0.11071 
parts per thousand in the same time. The total solids fell by a 
little less than one-half their quantity, while the chlorin fell by 
two-thirds of the amount present when the water table was high, 
May 23. 
§ 57. The chlorin in the water was no indication of the 
amount of total solids present except within the very wide limits 
giyen above, which were different for each individual well; further¬ 
more its quantity varied with the falling of the water table differ¬ 
ently from that of the total solids, and increased in a most irregular 
manner when it rose, especially when the rising of the water table 
was due to irrigation or to heavy rainfalls. Experiments made by 
filtering salt solutions through sandstones have shown that they 
have a considerable power to retain it. Something similar prob- 
