310 



The Cause of the Variation of the Emanation 

 Content of Spring Water. 



ByK. R. Ramsey. 



Last year at the annual meeting of this Society I presented a paper on 

 "Radioactivity of Spring Water" in which I called attention to the fact that 

 there was a variation of the radioactivity from time to time. During nine 

 months of the past year I have measured the emanation content of two 

 springs once every week. In a short time I discovered that there was a con- 

 nection between the radioactivity and the flow of the springs. The flow of 

 one of the springs was measured every week during six month.-. 



The springs are about 1.3 miles apart. One isuses out of coarse graval the 

 other issues from a crevice in the solid rock. Both springs are known as never 

 failing springs, however the flow of both are affected by the rain fall. They 

 both vary in the same manner but not to the same degree. The variation of 

 the 111. Cent, spring, the one measured, is much more then the Hottle spring. 

 The method of measuring the flow was by means of a horizontal weir, the 

 depth being measured and computed according to the usual formula. 



The radioctivity was measured by means of the 'Schmidt shaking method 

 and an emanation electroscope. The electroscope was standardized by 

 means of an emanation standard secured from the Bureau of Standards. 

 The Schmidt shaking method can be carried out at the spring. The accuracy 

 of the method when the measurements are made at the spring in 15 to 30 

 minutes is about 5 per cent. The observations for the nine months are shown 

 in the table I. The date of observation, the temperature, the flow in gallons 

 per day. and the emanation content of the water is given for each spring. 



It will be noted that the radioactivity of the Hottle spring is higher and 

 more constant than the 111. Cent, spring. In the same manner the How of the 

 Hottle spring is more constant than the 111. Cent, spring but it is not always 

 greater than the 111. Cent. It will be noted that the fluctuations of the radio- 

 activity are in the same general manner for both springs. 



This is better shown by means of curves Figure II. The full lines are for 

 the radioactivity the dotted line is for the flow. The curves have a general 



'Indiana Academy of Science Proceedings, 1914. 



