4ji Tranjit of Mercury, 



better object. Riceioli calls Mercury a falfe deceitful ftar 

 f/iJus dolofum), the eternal torment of aftronomers, which 

 eluded them as much as the terreftrial mercury did thealche- 

 mifts*. Lalande, that refpectable veteran of allronomy, 

 who has forty-fix years engaged with this celeftial rebel, in 

 his laft treatife on it, in the firft volume of the Tranfaelions 

 of ihe National Fnftitute, calls its courfe icne orbit c inextri- 

 cable. On account of this planet he ftudied the Greek lan- 

 vuao'c, that he might be able to read the old obfen ations in 

 Ptolomy's Ahnagefr in the original, and, of courfe, to ex- 

 plain them better; and in the younger part of his life he 

 lifed to get on the tops of the houfes, before fun-rife, to have 

 a view of Mercury above the foggy horizon of Paris. It is 

 natural, therefore, to fuppofe, that, after fo much labour and 

 exertion, Lalande would have given the belt tables of Mercury; 

 and this was really the cafe, fo far as they furpafled in accu- 

 racy the old tables of Ilalley and Caflini. He waited, 

 therefore, with anxious expectation for the tranfit of this 

 planet over the fun's difk on the 4th of May 1786. His 

 ©bfervations on that occafion were to be the touchftone of hi& 

 tables, and to reward him at length for the inccflant pains 

 and labour he had bellowed on them for nearly half a century. 

 The treacherous Hermes, however, inftead of fanetioning 

 thefc tables, proved that the author had erred more than half 

 an hourf- Since that time Triemecker of Vienna, and 

 lately Oriani of Milan, have emploved themfelves on this 

 planet: and as the laft, in particular, firft calculated the per- 



■ * Ahnugffli/rr, p. 56?: Nemo planetarvtm — Mercuric jmplicatior eft 

 — adeo ut cdelcftis Mercurius non minus Aftnmomos torferir, cpjam tcrref- 

 rri<: Alchtmiftas eludat. And in anorher place, p. 49S, he fays— Non mino- 

 ribus quipne fpirarum involucris vaferritnus planetarum fuffbratur fe hie 

 Hermes Aftronomorum conatibus, quam caduccus ipfius tortuofis anguium 

 circumfiexibxis. 



f J.alande's own words are — Une erreur de plus dedemi-beurevitH me 

 dinner un dementi. 



turbation, 



