APPENDIX 7 



REPORT ON THE ASTROPHYSICAL OBSERVATORY 



Sir: The Astrophysical Observatory was conducted under the fol- 

 lowing passage of the independent offices appropriation act approved 

 June 12, 1922: 



Astrophysical Observatory: For maintenance of the Astrophysical Observ- 

 atory, under the direction of the Smithsonian Institution, including assist- 

 ants, purchase of necessary books and periodicals, apparatus, making necessary 

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

 laneous expenses, $15,500. 



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, and also 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. 



A new solar observing station on Mount Harqua Hala, Ariz., was 

 erected in July, 1920, at the expense of funds donated for the purpose 

 by Mr. John A. Roebling, of Bernards ville, N. J., and this station 

 has been occupied as a solar radiation observing station by the Astro- 

 physical Observatory since October, 1920. 



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

 physical Observatory, 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 at Washington. — No observations were attempted at Wash- 

 ington. Mr. Fowle, Mrs. Bond, and the director, as much of his time 

 as possible, were engaged in computations necessary (1) to the search 

 for systematic errors in the work of Mount Harqua Hala, Ariz., and 

 the application of carefully determined corrections thereto; (2) to 

 the publication of a comparison of two years of observations at 

 Mount Harqua Hala, Ariz., and Mount Montezuma, Chile (see 

 Monthly Weather Review, February, 1923) ; (3) to the preparation 

 of a new set of curves for use from January 1, 1923, in the short 

 method of solar constant determination at Montezuma, Chile; (4) to 

 the search for systematic errors and the application of carefully de- 

 termined corrections to Montezuma results on the new basis; (5) to 



104 



