APPENDIX 7 



REPORT ON THE DIVISION OF RADIATION AND 

 ORGANISMS 



Sir: I have the honor to submit the following report on the activities 

 of the Division of Radiation and Organisms during the year ending 

 June 30, 1933: 



This branch of the operations promoted by private funds has for 

 its primary purpose the study of the dependence of plant growth on 

 radiation in various circumstances of temperature, humidity, and 

 carbon dioxide concentration in the air. The division was started 

 May 1, 1929, by the assistance of the Research Corporation of New 

 York, which has furnished an average of about $20,000 a year in 

 grants to promote its progress. To these sums have been added sums 

 from the income of the private endowment of the Smithsonian 

 Institution, so that an average expenditure somewhat exceeding 

 $25,000 annually has been made. 



The investigations proposed required considerable laboratory space 

 and office space. These were secured by clearing a part of the western 

 basement of the old Smithsonian Building and equipping it with 

 water, gas, and electricity, cementing the floor, and finishing and 

 painting the walls. Office space was obtained by finishing the interior 

 of the north tower and providing an elevator, whereby eight excellent 

 though small office rooms were made available. 



The earlier years of the investigation were very largely given over 

 to the invention and construction of special apparatus under the 

 direction of Dr. F. S. Brackett and Dr. Earl S. Johnston. Much glass 

 apparatus has been prepared by L. B. Clark, and in the shop equipped 

 by the funds of the Research Corporation L. A. Fillmcn has con- 

 structed many instruments of special design. Dr. E, D. McAlister 

 has been engaged in the preparation of thermocouples of high sensi- 

 tivity, the measurement of the energy distribution of absorption 

 spectra, and the preparation of spectroscopic apparatus, and has 

 assisted in the difi'erent researches as required. 



In addition to the personnel above named, W. H. Hoover has been 

 assigned to the special work on radiation and plant growth. Dr. 

 Florence E. Meier, a fellow of the National Research Council, has been 

 assigned to the study of the life and health of algae under difi'erent 



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