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I VOLUME 8 AUGUST. 1922 NUMBER 8 ■ 
I I 
I I 
1 PROCEEDINGS I 
OF THE 
1 National Academy 
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I OF Sciences 
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I OF THB 
I UNITED STATES OT AMERICA 
M . 
M 
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EXECUTIVE COMMITTEE 
Edwin BmwiCLL Wilson, Managing Editor 
Raymond Pbarl Vernon Kbllogo 
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I PUBUSHED MONTHLY 1 
I Publication Office: Eschenbach Printing Company, Easton, Pa, 1 
I Editorial Office: Harvard School of Public Health, Boston 17 | 
§ Home Office of the Academy: Washington, D. C. J 
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Batcred as second-class matter June 21, 1920, at the postoffice at Easton, Pennsylvania, under the act of August 24. 1912. 
Acceptance for mailing at special rate of postage provided for in section 1103, Act of October 8, 1917. Authorized June 18, 1920. 
Price per annum, $5.00 
