was working at the lunar theory, he applied to Flamsteed for his observations, by aid of which he hoped to test his calculations. Flamsteed could not or would not understand the purpose for which Newton wanted the observations, and put difficulties in the way of communicating them. In 1694 Newton writes (p. 139): ‘I believe you have a wrong notion of my method of determining the moon's motions. I have not been about making such corrections as you seem to suppose, but about getting a general notion of all the equations on which her motions depend.’ Newton, on a visit to Flamsteed in September 1694, obtained a number of observations, but by no means all he needed, and during much of the early part of 1695 Newton's work was suspended while he was ‘staying the time’ of the astronomer royal. Again, 29 June 1693, Newton thanked Flamsteed for some solar tables, but wrote: ‘These and almost all other communications will be useless to me unless you can propose some practicable way or other of supplying me with observations. … Pray send me first your observations for the year 1692.’ Flamsteed replied with an offer of observations from 1679 to 1690, which Newton had not specially asked for. The correspondence ended 17 Sept. 1695, and Newton's work on the lunar theory was uncompleted (Edleston, Cotes Corr. p. lxiv, n. 117, &c.; Baily, Life of Flamsteed, pp. 139 seq.; Supplement, p. 708). Leibnitz in a letter to Romer, 4 Oct. 1706, declared: ‘Flamsteadus suas de luna observationes Newtono negaverat. Inde factum aiunt quod hic quædam in motu Lunari adhuc indeterminata reliquit.’ Flamsteed's ill-health, bad temper, and extraordinary jealousy of Halley contributed to this unhappy result. Flamsteed continued to observe, and in 1703 made it known that he was willing to publish his observations ‘at his own charge,’ provided the public would defray the expense ‘of copying his papers and books for the press.’ Next year Newton, as president of the Royal Society, recommended the work to Prince George of Denmark, the husband of Queen Anne. The prince asked Newton and others to act as referees, and early in 1705 they drew up a report recommending the publication. The prince approved, and agreed to meet the expense.
Difficulties began in March 1705. Newton wished to have the observations printed in one order; Flamsteed preferred a different one. For two years Flamsteed, who had conceived an intense jealousy of Newton, pursued him with recriminations which only injured their author [see Flamsteed, John]. The first volume was finished in 1707, and preparations made for printing the second. The referees insisted on receiving the copy for this volume before the printing commenced, and it was put into their hands, Flamsteed says, in a sealed packet, 20 March 1708, copied out on to 175 sheets. Subsequently, in 1712, Flamsteed declared that this ‘imperfect copy’ Newton ‘very treacherously broke open’ in his absence and without his knowledge; but in an earlier letter of 1711 Flamsteed himself rebutted this charge of bad faith by acknowledging that the papers were unsealed in his presence. In October 1708 Prince George died, and the printing was suspended. After three years it recommenced. In 1710 the Royal Society were made visitors of Greenwich Observatory, and on 21 Feb. 1711 the secretary, Dr. Sloane, was ordered to write to the astronomer royal for the deficient part of his ‘Catalogue of the Fixed Stars,’ then printing by order of the queen. Flamsteed angrily declared that the proof-sheets which had been sent to him contained many errors, and asserted at a meeting with Newton, Sloane, and Mead, October 1711, that he had been robbed of the fruit of his labours. Our only accounts of this interview are the three given by Flamsteed in his ‘Autobiography,’ or in his papers, in which the blame is all thrown on Newton. The referees proceeded to print, and made Halley editor. Flamsteed indulged in abuse directed largely against Newton, and finally determined to reprint his observations at his own expense. These he left almost ready for publication at the time of his death in 1719. They were published in 1725. Meanwhile the copy left with Newton, together with the first volume printed in 1707, was issued, as edited by Halley, in 1712. Before his death Flamsteed, through a change of government, obtained possession of the three hundred copies which were undistributed, and, taking from them that part of the first volume which had been printed under his own care, burned the rest.
The dispute with Leibnitz about the invention of the theory of fluxions was of longer duration, and was more bitterly contested. We have seen that the discovery was made by Newton during 1665 and 1666. His tract on the subject, ‘De Quadratura Curvarum,’ was, however, not printed till 1704 in an appendix to his ‘Optics,’ though the principles of the method were given in the ‘Principia,’ book ii. lemma ii. in 1687. They had been communicated in letters by Newton to Collins, Gregory, Wallis, and others from 1669 onwards.
Leibnitz had been in England in 1673, and had made the acquaintance of Collins and