APPENDIX 1 



REPORT ON THE ASTROPHYSICAL OBSERVATORY 



Sir: The Astrophj^sical Observatory was conducted imder the 

 following passage of the independent offices approjoriation act ap- 

 proved June 7, 1924: 



Astrophysical Observatory: For maintenance of the A.stropliysical Observa- 

 tory, under the direction of the Smithsonian Institution, including assistants, 

 purchase of necessary books and periodicals, apparatus, makini? necessary ob- 

 servations in high altitudes, repairs and alterations of buildings, and miscel- 

 laneous expenses, $21,580. 



The observatory occupies a number of frame structures within 

 an inclosure of about 16,000 square feet south of the Smithsonian ad- 

 ministration building at Washington, a cement observing station and 

 frame cottage for observers on a plot of 10,000 square feet leased 

 from the Carnegie Solar Observatory on Mount Wilson, Calif., and 

 also a solar observing station on Mount Harqua Hala, Ariz., erected 

 in 1920 at the expense of private funds contributed by Mr. John A. 

 Roebling, of Bernardsville, N. J. 



The present value of the buildings and equipment for the Astro- 

 physical Observator}^ owned by the Government is estimated at 

 $50,000. This estimate contemplates the cost required to replace 

 the outfit for the purposes of the investigation. 



WORK OF THE YEAR 



Solar variation and forecasting. — The chief object of the work 

 at present is to secure the most exact measurements of the variation 

 of the sun in order to provide proper data for studying the influ- 

 ence of solar changes on weather conditions of the United States 

 and the whole world. Accordingly, the efforts of the staff were de- 

 voted mainly to this purpose. The Government appropriation? 

 were sufficient only to maintain the work at Washington and Ari- 

 zona, and to pay salaries of two observers at the exceptionally favor- 

 able station at Montezuma, Chile. This station was established in 

 1918, and has been maintained ever since by private funds of the 

 Institution, supplemented by gifts of Mr. Roebling. Owing to fur- 

 ther support by Mr. Roebling, it has been possible to receive daily 

 telegrams reporting the solar radiation observations in Chile and 

 in Arizona. These arrive at Washington within 24 hours of the 

 observations in the field. 



76041—26 8 101 



