THE RADIOACTIVITY OF SOME SPRING WATERS 
AT MADISON, WISCONSIN. 
HERMAN SCHLUNDT. 
The radioactivity of underground Waters is generally due to 
the presence of a very minute quantity of radium emanation. 
This disintegration product of radium, being a gaseous sub¬ 
stance, can he easily separated from the water by boiling for a 
few minutes. By collecting all the dissolved gas in a known 
volume of water the quantity of emanation present may be 
readily determined by introducing the water gas into a suitable 
form of electroscope or electrometer. 
During the past summer (1908) several of the spring waters 
in the vicinity of Madison were tested for radioactivity by mak¬ 
ing quantitative determinations of the radium emanation car¬ 
ried in solution. The method of conducting the tests will be 
outlined first and then will follow the results of the experiments 
and some comparative data. 
As the emanation quickly escapes from running water, and to 
some extent from stored water, an effort was made to obtain the 
samples directly from the spring where the water issues from 
the ground. Since most of the springs were walled in, the 
water had to be drawn into the collecting vessel by means of 
tubing the intake end of which was held where the water issued. 
In this way the influx of water from the overflow basin was 
minimized. The collecting vessel was filled nearly full and was 
then tightly stoppered. The container used was made of gal¬ 
vanized iron, and served as a boiler later in the separation of 
the dissolved gases. Its capacity was 5.34 liters. The samples 
