304 ANNUAL REPORT SMITHSONIAN INSTITUTION, 19 31 



Dr. John J. Abel, of the Johns Hopkins University, for his work on ductless 

 glands, animal tissues, and fluids. The second, in 1929, went to Dr. Werner 

 Heisenberg, of the University of Leipzig, for his contribution to matrix mechan- 

 ics and for his exposition of the principle of indeterminance ; and the third, 

 also in 1929, to Dr. Bergen Davis, of Columbia University, for the contribution 

 of the Davis double X-ray spectrometer and other brilliant achievements in the 

 field of atomic physics. 



It is indeed a pleasure to have the Research Corporation represented on this 

 platform by its president, Mr. Poillon, and by its founder, Doctor Cottrell, and 

 to have the Smithsonian Institution represented by its chancellor, the Hon. 

 Charles Evans Hughes, Chief Justice of the United States, who will now present 

 the awards. 



[After extemporaneous remarks by Mr. Elon Hooker, a director 

 and past president of the Research Corporation, Doctor Abbot 

 continued] : 



I have the honor, ladies and gentlemen, to present Chief Justice Charles 

 Evans Hughes. 



REMARKS OF CHIEF JUSTICE CHARLES EVANS HUGHES 

 Chancellor of the Smithsonian Institution 



DocTOB Douglass : You have been diligently engaged for nearly 30 years in 

 making exact measurements of conditions of former centuries as they stand 

 recorded in the growth of ancient trees. You have pursued these studies in 

 many lands. You have devised ingenious instruments to further your re- 

 .searches. Your work has been crowned with success in several directions. 

 You have found evidences of periodicities in weather which seem to imply cor- 

 responding periodicities in the radiation of the sun. You have established an 

 exact chronology for more than a thousand years, thus dating the prehistoric 

 culture of the Indians of the Southwest from the timber rings of their habi- 

 tations. 



In recognition of these achievements, the Research Corporation of New York 

 has awarded to you through tlie Smithsonian Institution a grant of $2,500. In 

 token of this award, I now, as chancellor of that Institution, hand you this 

 commemorative medal, and wish for you equal success in your future researches. 



TREE RINGS AND THEIR RELATION TO SOLAR VARIATIONS AND 



CHRONOLOGY 



By A. E. Douglass, University of Arizona 



[With 5 plates] 



The studies of tree rings described in this paj^er touch closely upon 

 several major sciences. This is because annual rings, like annual 

 varves, measure the passage of years, and time is a prime considera- 

 tion in all branches of knowledge. Hence we find ourselves at once 



