694 EEPORTS OF ASTRONOMICAL OBSERVATORIES. 



Troughton, Pistor, Steinheil, aud Breithaupt ; two heliotropes 

 by Meyerstein. 



ObSERVATIOTs'S DURINPr THE PAST YEAR: 



(6) Observatious on planets and comets. 



(c) Observations on comets with the six-foot refractor of Merz. 



Principal publication during past year, 1880, 1881. Prof. Dr. 

 Klinkerfues : Tobias Mayer's grossere Mondkarte, nebst detailzeich- 

 nuugen, 13 Karten, mit Text. 



Greenwich, England. 



Royal Observatory. 



Longitude from Washington, 5^^ 8"^ 12^09 E. 

 Latitude, 51o 28' 38".4 I^. 



Authority for latitude and longitude : Nautical Almanac, Greenwich 

 observations 1878. 

 Directors: J. Flamsteed, 1G75; 

 E. H ALLEY, 1720; 

 J. Bradley, 1742 ; 

 I^. Bliss, 1762; 

 N. Maskelyne, 1765; 

 J. Pond, 1811; 



Sir G. B. Airy, K. C. B. (Astronomer Eoyal), 1835. 

 Chief assistant : W. H. M. Christie. 

 First-class assistants: Edwin Dunkin; 

 G. S. Criswick. 

 Second-class assistants : A. M. W. Downing; 

 E. W. Maunder; 

 W. G. Thackeray; 

 And one vacancy. 

 Founded by royal statute on the 4th May, 1675. Built in the park at 

 Greenwich by Christopher Wren, architect. At first it consisted 

 merely of an octagonal tower. In 1860 Flamsteed put up an addi- 

 tional wing to accommodate the mural sector, with the help of which he 

 made his catalogue of stars. The board of visitors was created in 1710. 

 In 1749 and the years immediately following great improvements 

 and additions were made. The sector used by Bradley in discovering 

 the phenomenon of aberration was transferred to Greenwich, and Bird 

 supplied a mural quadrant with a radius of 7 feet lOi inches (2™.4), 

 besides remodeling the one made by Graham. A statute of 1765 con- 

 firmed the right of supervision vested in the Eoyal Society and exer- 

 cised by the board of visitors. In 1770 two revolving domes were con- 

 structed upon the turrets, and these have served as models for all 

 revolving turrets since constructed. In 1772 the first achromatic 

 object-glass ever used at Greenwich was attached to the south quad- 

 rant. It had an aperture of 2§ inches {6S millimeters). In 1779 the 



