AIDS OF THE NEWTONIAN PERIOD. 477 



at Uraniburg, and that of the Landgrave of Hesse Cassel, at Cassel, 

 where Rothman and Byrgius observed. But by far the most impor- 

 tant observations, at least since those of Tycho, which were the basis of 

 the discoveries of Kepler and Newton, have been made at Paris and 

 Greenwich. The Observatory of Paris was built in 1GG7. It was there 

 that the first Cassiui made many of his discoveries ; three of his de- 

 scendants have since labored in the same place, and two others of his 

 family, the Maraldis ; 7 besides many other eminent astronomers, as 

 Picard, La Hire, Lefevre, Touchy, Legentil, Chappe, Mechain, Bouvard. 

 Greenwich Observatory was built a few years later (IGVo); and ever 

 since its erection, the observations there made have been the founda- 

 tion of the greatest improvements which astronomy, for the time, re- 

 ceived. Flamsteed, Halley, Bradley, Bliss, Maskelyne, Pond, have 

 occupied the place in succession : on the retirement of the last-named 

 astronomer in 1835, Professor Airy was removed thither from the 

 Cambridge Observatory. In every state, and in almost every princi- 

 pality in Europe, Observatories have been established ; but these have 

 often fallen speedily into inaction, or have contributed little to the 

 nrogress of astronomy, because their observations have not been pub- 

 lished. From the same causes, the numerous private observatories 

 which exist throughout Europe have added little to our knowledge, ex- 

 cept where the attention of the astronomer has been directed to some 

 definite points; as, for instance, the magnificent labors of the Her- 

 schels, or the skilful observations made by Mr. Pond with the Westbury 

 circle, which first pointed out the error of graduation of the Greenwich 

 quadrants. The Observations, now regularly published, 8 are those of 

 Greenwich, begun by Maskelyne, and continued quarterly by Mr. 

 Pond ; those of Konigsberg, published by Bessel since 1814 ; of Vienna, 

 by Littrow since 1820; of Speier, by Schwerd since 1820 ; those of 

 Cambridge, commenced by Airy in 1S2S; of Armagh, by Robinson 

 in 1829. Besides these, a number of useful observations have been 

 published in journals and occasional forms; as, for instance, those of 

 Zach, made by Seeberg, near Gotha, since 1788; and others have 

 been employed in forming catalogues, of which we shall speak shortly. 

 [2d Ed.] [I have left the statement of published Observations in 

 the text as it stood originally. I believe that at present (1847) the 

 twelve places contained in the following list publish their Observations 

 quite regularly, or nearly so ; Greenwich, Oxford, Cambridge, Vienna, 



' Mont. iv. 3-1C. * Airy, Kep. p. 128. 



