NOTES TO BOOK VII. 299 



Moon which is given as his in David Gregory's Astro- 

 nomic Elementa*. He also obtained from Flamsteed the 

 diameters of the planets as observed at various times, and 

 the greatest elongations of Jupiter's Satellites, both of 

 which Flamsteed says, he made use of in his Principia. 



I regret much to have done Flamsteed injustice in 

 my first Edition by stating that he withheld his observa- 

 tions from Newton, and by ascribing to their differences 

 on this subject, the angry intercourse which took place 

 between them at a later period. Newton in his letters 

 to Flamsteed in 1694 and 5 k acknowledges this service. 

 The quarrel on the subject of the publication of Flam- 

 steed's Observations took place at a later period. Flam- 

 steed wished to have his Observations printed complete 

 and entire. Halley, who, under the authority of Newton 

 and others, had the management of the printing, made 

 many alterations and omissions, which Flamsteed con- 

 sidered as deforming and spoiling the work. The advan- 

 tages of publishing a complete series of observations, now 

 generally understood, were not then known to astronomers 

 in general, though well known to Flamsteed, and earn- 

 estly insisted upon in his remonstrances. The result was 

 that Flamsteed published his Observations at his own 

 expense, and finally obtained permission to destroy the 

 copies printed by Halley, which he did. In 1726, after 

 Flamsteed's death, his widow applied to the Vice-Chan- 

 cellor of Oxford, requesting that the volume printed by 

 Halley might be removed out of the Bodleian Library, 

 where it exists, as being " nothing more than an erroneous 



* In the Preface to a Treatise on Dynamics, Part i., published in 

 K!o), I have endeavoured to show that Newton's modes of determining 

 several of the lunar inequalities admitted of an accuracy not very 

 inferior to file modern analytical methods. 



