File:Radioactivity of the thermal waters of Yellowstone National Park (1909) (14754420241).jpg

Identifier: radioactivityoft00schl (find matches)
Title: Radioactivity of the thermal waters of Yellowstone National Park
Year: 1909 (1900s)
Authors: Schlundt, Herman, 1869-1937 Moore, Richard B. (Richard Bishop), 1871-1931
Subjects: Geothermal resources Radioactive substances in rivers, lakes, etc Freshwater radioecology
Publisher: Washington : G.P.O.
Contributing Library: Harold B. Lee Library
Digitizing Sponsor: Brigham Young University

View Book Page: Book Viewer
About This Book: Catalog Entry
View All Images: All Images From Book
Click here to view book online to see this illustration in context in a browseable online version of this book.

Text Appearing Before Image:
on by the use of the apparatus shown in figure 3. Asthe gas issued relatively slowly, ten minutes was consumed in passingthe accumulating gases along the circuit through electroscope No. 1.About 1,100 cubic centimeters of gas was transmitted, as measuredby 15 squeezes of the hand bellows. The first readings of the fallof the charged leaf were taken thirty seconds after the gas deliverywas stopped. In this case no decrease in activity was observed duringthe first two minutes of observation. Hence thorium emanation wasabsent. In the course of ten minutes the leak increased about 12 percent, which is characteristic of radium emanation. The gas evidentlywas relatively rich in emanation, as the leak was fully 1,000 timesthe usual air leak of the instrument. Our field journal shows that 60small divisions of the scale were passed over by the leaf in eleven andsix-tenths seconds. After twelve minutes of observation the gas wasblown out and the electroscope set aside for a time to wait for the
Text Appearing After Image:
OF YELLOWSTONE NATIONAL PAEK. 19 decay of the induced activity. Later in the day a quantitative deter-mination of the radium emanation present in the escaping gas wasmade with the same electroscope. Ninety cubic centimeters of gaswere collected over water (temperature 40° C.) and introduced into thepartially exhausted electroscope. At maximum activity the leaf fell23.6 small scale divisions per minute after deducting the normal airleak, which was 0.2 division per minute. The volume of the gas samplereduced to normal temperature and pressure is 56.3 cubic centi-meters. a In this electroscope a leak of one division per minute repre-sented 2.8 X 104 grams uranium or 10.64 X 1011 grams radium. Theactivity of the gas per liter, in terms of the uranium standard, is henceexpressed by the following equation: 23.6 X 2.8 X10~4X 1,000 117v,in-356.3 -ii/Xiu . Expressed in terms of the radium standard the activity equals117 X 103 X 3.8 X 10~7 = 44.5 X 10~9. The value of the ionization current per

Note About Images