REPORT OF THE SECRETARY bs 
Professor Marvin, Chief of the United States Weather Bureau, 
replied: 
UNITED STATES DEPARTMENT OF AGRICULTURE, 
OFFICE OF THE CHIEF, WEATHER BUREAU, 
Washington, April 28, 1924. 
Dr. CHARLES G. ABBOT, 
Assistant Secretary, Smithsonian Institution, 
Washington, D. C. 
Dear Doctor Apsot: Replying to your letter of the 12th instant, I am very 
glad of the opportunity of expressing my views regarding the desirability of 
continuing the solar radiation station at Montezuma, Chile, after July, 1925. 
When we remember that without the heat and light received from the sun, life 
on the earth would be impossible, it becomes evident that any facts that can be 
established relative to the sun, and especially as to the rate at which it radiates 
heat and light to the earth, are of fundamental importance. 
With reference to the work of the Astrophysical Observatory of the Smith- 
sonian Institution, I have already made the following statement in the Monthly 
Weather Review for March, 1920, page 150: 
“The solar radiation investigations conducted by Doctor Abbot constitute a 
monumental research of the highest possible order and command only the 
admiration of all. * * * The whole question of short and long period solar 
variability, and the terrestrial response thereto in terms of weather, is obvi- 
ously one of great importance to applied meteorology and to science generally. 
It is very necessary, therefore, that the splendid observational work done by the 
Astrophysical Observatory be generously supported and extended.” 
At this point I would like to say emphatically that I consider the systematic 
and continuous observation of the intensity of solar radiation to be of basic 
and fundamental importance, and I think it is a mistake to try to justify these 
observations on the ground that they will enable us to improve the forecasting 
of the weather from day to day. We do not know as yet what may be the 
ultimate practical value of the knowledge to be gained by a long series of 
observations, but the collection of the observations is necessary because the data 
constitute important facts of a fundamental, scientific character, and are pretty 
certain ultimately to have important practical applications to the welfare of 
man. The basic research is fully justified on its own merits, leaving the practi- 
cal application of the information gained to be developed in the future. 
For the determination of the law of the variability of solar radiation continu- 
ous observations are required for a long period of years at two or more stations 
as widely separated as possible. The stations of the Astrophysical Observatory 
at Montezuma, Chile, and on Mount Harqua Hala, Ariz., seem tc be admirably 
adapted for this observational work, and the observatory staff has the requisite 
skill and experience to handle the delicate apparatus required and make the 
necessary complicated reductions. The small sum required to maintain the 
station at Montezuma, now that it is equipped, will in my opinion be money 
well invested. 
Very truly yours, 
C. F. Marvin, Chief of Bureau. 
Doctor Simpson, director of the Meteorological Office of the Air 
Ministry of Great Britain, replied: 
METEOROLOGICAL OFFICE, AIR MINISTRY, 
ADASTRAL HOUSE, KINGSWAY, 
London, W. C. 2, May 14, 1924. 
DeEsR Doctor Appot: I have received your letter dated April 12 asking for 
my opinion regarding the desirability of maintaining the Montezuma solar 
station after July, 1925. 
