CONTENTS 
Tre fete CES ih cl Soe ee La wh he es ee cad Poe ge al 
Wartime activities Of the Institution... 2.02.0 S. 222424222 tes 
Summary of the year’s activities of the branches of the Institution. Bet 8 
Pbherestablishmentas sac is 2 Me eee CE ee Ce See et eis 
Mesa OUNCE EOREOINGR 2 20) Step ee er ee Pl ee ah 
PET ATICOS en Nee ees. kes see ee bee ee eS es ee 
velit Arthur lecture: .c.0 2 cs 8 oh eee Pe tee Ser eee 
OTIS SY 07S IR EE ER ae nr see 2s ek eee Aue 
De ah Re os ie ee er ie ees oe Ne tnd eee Linea t io 
Appendix 1. Report on the United States National Museum_-_--_---_ ~~ 
2. Report on the National Gallery of Art____-______- Bie die 
3. Report on the National Collection of Fine Arts________-_-- 
4. Report on the Freer Gallery of Art._._._-2-.---2_=+-.---=- 
5. Report on the Bureau of American Ethnology___-_-----_--- 
6. Report on the International Exchange Service_____-__--_-_- 
7. Report on the National Zoological Park --_--__---.--------- 
8. Report on the Astrophysical Observatory--_-_-__--_------ 
OU Reporh On the Mbrany 2) = oe ne eA eee ee 
20. Renot, Of MUONCHGIONS “22002220 y oe eben Soe 
Report of the executive committee of the Board of Regents____-_-_-_--_- 
GENERAL APPENDIX 
Solar variation and weather, by Charles G. Abbot_.___-___-____--_____- 
Astronomy in a world at war, by A. Vibert Douglas- ------_- 2 Vin ie Syale oi 
The structure of the universe, by Claude William Heaps__--_--_-_-_-_-- 
Industrial science looks ahead, by David Sarnoff_________________- eres 
The new microscopes, by R. E. Seidel and M. Elizabeth Winter-_-_-_-_____ 
Radio acoustic ranging (R. A. R.), by Commander K. T. Adams_-______ __ 
The David W. Taylor Model Basin, by Rear Admiral Herbert 8. Howard_ 
Research for aeronautics—its planning and application, by W. S. Farren__ 
Human limits in flight, by Byran H. C. Matthews___-_---_-_-----_-_-- 
Trans-Arctic aviation, by Lt. Elmer Plischke--_______---.-.--_-_-_---___ 
Our petroleum resources, by Wallace E. Pratt_....---_---------------- 
Woods and trees: Philosophical implications of some facts of science, by 
ne ene kellie tc TeC Ker tae Ne Unt me eae ete. bs ee eee Le 
Biology and medicine, by Asa Crawford Chandler_-_--___-----_--_---___- 
me lecnst pineies Dy b.a. UU WarOvccos. 22 20545. eee SL 
whe coding moh, by i..A. Porter... oo... 22 S22. 22nd ol. ee ne 
Grassland and farmland as factors in the cyclical development of Eurasian 
FRELOEY A OVG). eUNBELD mI bie. Stes os. ok el See eee eck 
Southern Arabia, a problem for the future, by Carleton S. Coon__-_____-_- 
The New World Paleo-Indian, by Frank H. H. Roberts, Jr__-__-_____-- 
Paster aend. ty Almom Metraus. 275 oe a 
fers ruses, OY ©, L)-CAdMmam. ee oe 8 See aa 
The development of penicillin in medicine, by H. W. Florey and E. Chain_ 
Recent advances in anesthesia, by John C. Krantz, Jr___-__________-_-- 
Aspects of the epidemiology of tuberculosis, by Leland W. Parr-_-------- 
