ASTRONOMY FOR 1889, 1890. 167 



United States Naval Observatory: McXair.— The reports of 

 the snperiutendents of the Naval Observatory show no material change 

 in the character of the work from the years immediately preceding. 

 On June 28, 1890, Capt. F. V. McNair succeeded Capt. R. L. Phythian 

 as Superintenrlent, Capt. McNair's report covering the fiscal year June 

 30, 1890. The walls of the main building for the new observatory were 

 practically completed by the end of 1890 ; also the great equatorial and 

 clock and observer's rooms. The iron work for the three transit-circle 

 rooms is ready. The buildings will scarcely be ready for occupancy 

 before the summer of 1892. 



Upsala: Duner. — From an extensive series of spectroscopic obser- 

 vations to determine the rotation period of the sun, it appears that the 

 period varies from 25.5 days to 38.6 days, increasing with the helio- 

 graphic latitude. 



Vienna {von Kuffmr's observatory) : Eerz, — The latitude from obser- 

 vations with the Repsold meridian circle, 1889 -'90, is +48^ 12' 46".67. 



Washington (Catholic University of America) : SearJe. — A small 

 observatory has been built at the Catholic University in the suburbs 

 of Washington (D. C), and is under the direction of Rev. G. M. Searle. 

 The position is latitude + 38° 5G' 15" ; longitude 5»» 8°^ 0«.0 west of 

 Greenwich. The telescope, which will be mounted in 1891 is 9 inches 

 aperture, 9 feet focus, glass and tube by Clacey, mounting by Saeg- 

 muller (Fauth & Co.). The cells and center piece of tube are made of 

 aluminum. A small meridian circle, and photographic and spectro- 

 scopic apparatus will also be provided. A 5inch telescope is now in 

 use. (1890.) 



Washington. {See^ also, Georgetown; also, Smithsonian astro- 

 physical observatory ; also, U. S. Naval Observatory.) 



Washburn: ComstocJc. — The sixth volume of publications contains 

 the meridian observations of 1887 and observations of double stars. 



Yale : Neioton. — The heliometer triangulation of the region near the 

 north pole has been completed, and souie observations of Iris, Victoria 

 and Sappho have been obtained in cooperation with the observatories 

 at the Cape of Good Hope and Leipsic, for the determination of the 

 solar parallax. 



Zurich: Wolf. — Physical observations of the sun. 



astronomical instruments. 



In the fourth part of the Bulletin of the Astro-photographic con- 

 gress. Dr. H. C. Vogel describes the photographic refractor constructed 

 for the observatory at Potsdam by the Repsolds. This instrument has 

 two objectives; eye-piece and plate-holder are in the same tube, con- 

 forming to the resolutions of the congress in 1887, but the peculiarity 

 is in the form of mounting, which is quite different from both the Eng- 



