GQG EEPOETS OF ASTROXOMICAL OBSERVATORIES. 



portable transits aud zeuitli telescopes combined, used on Transit of 

 Venus Expeditions. 



(c) Equatorial instruments: one made by Alvan Clark & Sons; 

 aperture of objective, 26 inches; magnifying powers of eye-pieces, 120 

 to IGOO. (c') One made by Merz: 9.02 inches aj^erture; powers, 90 to 

 900. {c") Eight 5- inch equatorials by Alvan Clark & Sons, used on 

 Transit of Venus Expeditions. 



(e) Photometer: one nebula-photometer (Hastings' pattern) for use 

 with the 26-incIi equatorial. . 



(/) Chronograjyhs : some 10 or 12 in all, of various kinds. 



{g) ClocJx's: mean time, two; sidereal, six. 



(//) Chronometers: mean time; all the chronometers of the United 

 States Navy are kept here. Sidereal, eight, by Negus. 

 Work proposed for the coming year : 



The same as in former years. 

 Additional information : 



[The following is a short abstract of the annual report of the Super- 

 intendent of the Observatory to the Chief of the Bureau of Navigation, 

 and in it will be found details additional to the information presented 

 above.— E. S. H.] 



United States Naval Observatory, 



Washington, October, 20, 1879. 



******* 



The 26-ineh equatorial. — This instrument has been in charge of Prof. 

 Asaph Hall, with Prof. Edward S. Holden as assistant until Febru- 

 ary, 1880, since which time Prof. Edgar Frisby has been the assistant. 

 The instrument is now in good order, and it is in constant use. It has 

 been employed as in previous years in the observation of satellites, dou- 

 ble stars, and nebulae. 



The transit circle. — This instrument has been employed during the 

 year under the direction of Prof. J. K. East3IAN, who was assisted by 

 Prof. Edward S. Holden as an observer since Ai)ril 1, 1880 ; Prof. 

 Edgar Frisby until December 10, 1879; Assistant Astronomer A. N. 

 Skinner during the year ; Assistant Astronomer il. M. Paul until his 

 resignation, July 1, 1880, and Assistant Astronomer IT. S. Pritchett 

 until his resignation, February 1, 1880. Mr. JNIiles Kock has been em- 

 l)loyed as a temporary assistant astronomer since July 1, 1880; and Mr. 

 William C. Winlock has been similarly employed since August 2, 1880. 

 Mr. WiNSLOW Upton has been employed as a computer since July IG, 

 1880. Lieut. E. Longnecker and Lieut. A. H. Vail have been employed 

 in reducing transit-circle observations, the former during the year and 

 the latter since April 23, 1880. 



The observations have been confined to — 



1. Stars of the American ej^hemeris for clock aud instrumental cor- 

 rections. 



2. Sun, moon, major and minor planets. 



3. Stars whose occultations w^ere observed in connection with obser- 

 vations of the transit of Venus in 1874. 



4. Standard stars for a catalogue of zone observations. 



5. Such stars of the British Association catalogue between 120° 0' 



