The Ground Water. 
13 
end of the plot and lower at the east end than in 1897. The aver¬ 
age height of the water table at the west end of the plot for May, 
1897, was 9.80 feet, and for the same month in 1898 it was 9.98 
feet for the east end; for May, 1897, it was 8.11, and for May, 1898, 
7.55 feet. The rainfall in the two years differed both in its amount 
and distribution ; there was also another changed condition, the 
plot had been divided into sections 100 feet long by 25 feet wide, 
and the alternate sections had received a heavy dressing of manure. 
These conditions undoubtedly had an effect upon the movement of 
the soluble salts in the soil and also upon the salts themselves. 
§ 34. There was a remarkable change in the amount of the 
total solids contained in the waters of wells A and C between May 
16th and 23d, each containing less by 14.3 parts per thousand 
on the later date. The waters of the wells contained from 3.57 to 
5.71 parts per thousand more total solids on May 24, 1898, than on 
this date in 1897, except in the case of well D, the water of which 
contained 3.43 parts per thousand less. 
§ 35. An examination of the results obtained in 1898 corrob¬ 
orate those of 1897, i. e., that as a rule, the solids in the waters 
fell as the water table fell, and that a sufficient rainfall or an appli¬ 
cation of water to the surface was followed by an increase in the 
amount of salts held in solution by the ground water. 
§ 36. The amount of water necessary to raise the height of 
the water table and at the same time produce an increase in the 
amount of the salts in the ground water was not observed. I have 
already stated that a rainfall of a few tenths of an inch was fol¬ 
lowed by a disproportionate rise in the height of the water table. 
In the particular instances referred to we unfortunately made no 
determination of the total solids immediately before and after the 
change of the w r ater level. 
# 
§ 37. In May, 1898, there were nine days on which no rain 
fell. The aggregate rainfall for the 3d, 4th and 5th was 1.66 
inches, this was followed by a rise in the height of the water table, 
and though there were daily light rains, except on the 10th, until 
the 16th the water table fell by 0.2 of a foot. In this interval 0.69 
of an inch of rain had fallen, 0.22 and 0.24 of an inch being the 
largest amounts for any one day, an amount which under other con¬ 
ditions had been sufficient to cause a rise. 
§ 38. The total solids present in the waters of wells A and 
C were very high at this date, the 16th, containing 6.1043 and 
4.3414 parts per thousand respectively, while those of wells B and 
I) were much lower, 2.9000 and 2.1000 respectively; but seven 
days later they had fallen in wells A and C and risen in wells 
