(326 EEPOETS OF ASTRONOMICAL OBSERVATORIES. 



Ann Arbor, Michigan. 



Detroit Observatory, 



Longitude from Washington, 26"* 43M W. 

 Latitude, 42o 16' 48". N. 

 Directors : F. Brunnow, 1854 ; 

 J. C. Watson, 1858; 

 M. W. Harrington, 1879. 

 Annex of the University of Michigan. Projected in 1852, commenced 

 in 1853, completed in 1854. The principal structure is surmounted by a 

 dome and has two wings. About thirty i)lanetoids have been discov- 

 ered there. 



Annapolis, Anne Arundel County^ Maryland. 

 TJ. 8. Naval Academy Observatory. 



Longitude from Washington, 2"° 15^61 E. 



Latitude, 38^ 58' 53".48 N. 



xYuthority for latitude, Professor Chatjvenet ; for longitude, United 

 States Coast Survey. 



Director : Lieut. Commander P. F. Harrington, head of department 

 of Astronomy, Navigation, and Surveying. 



Assista7its : 1. Lieut. Commander C. J. Train, U. S. Navy ; 



2, Lieut. Commander E. P. Eodgers, U. S. Navy ; 



3. Lieut. W. J. Barnette, U. S. Navy. 



Instruments: 



(a) Meridian circle: one; makers, Kepsold, Germany; diameter of 

 circles, 30 inches ; divided to 2' ; read by 4 microscopes to 2". Aperture 

 of objective, 4 inches ; for observations of the sun, aperture employed, 

 — inches; magnifying power ordinarily employed, 80 diameters. 



[h) Meridian transit instrument: maker, Wurdemann; aperture, 2 

 inches ; magnifying power, 40 diameters. 



(c) Equatorial instriLment: makers, Al van Clark & SoNS ; aperture 

 of objective, 7f inches; magnifying power of eye-pieces, 40, 106, 553, 

 and 966 ; micrometer eye-pieces, 89, 226, 673. 



(/) Chronograplis : one Morse fillet; one Transit of Yenus Commis- 

 sion. 



(r/) ClocTi: one sidereal; makers, Arnold, Chas. Frodsh AM, London. 



{U) Chronometers: five, mean time; makers, Negus, Nos. 1030, 1088, 

 1260; Dent, 2099; Hatton, 262: two sidereal; maker, Negus, Nos. 

 1520, 1527. 



(i) Miscellaneous : one Talcott's zenith telescope ( WDrdemann) ; one 

 Transit of Yenus telescope (Stackpole); portable transit (Wurde- 

 mann). 



The officers attached to the observatory are not practical astronomers, 



