Catalogue Entry: OTHE00079

Chapter XVIII

Author: David Brewster

Source: Memoirs of the Life, Writings, and Discoveries of Sir Isaac Newton, vol. 2 (Edinburgh: 1855).

[Normalized Text] [Diplomatic Text]


Rigaud, Hist. Essay, p. 104.

[2] Conduitt's Manuscript notes.


Dated 10th August 1691, published in Baily's Flamsteed, p. 129.


August 27, 1691, unpublished.


February 24, 1692. Baily's Flamsteed, pp. 129-133.


In sending a copy of an unpublished letter on Earthquakes to a mutual friend, dated April 10, 1693, Flamsteed says, "Give my humble service to Mr. Newton, and let him know I owe him another concerning the present state of my labours, which I shall not fail to pay him now in a short time. It may satisfy him, that they go on successfully, and tend towards what they were designed for. I have thirty maps of the constellations drawn, having observed 2200 fixed stars visible by the naked eye, and having about as many left to observe, as will make them above 3000, which is above double of the old catalogues."


This work, with a preface and note by the editor, is entitled An Account of the Rev. John Flamsteed, the first Astronomer-Royal, compiled from his own MSS., and other authentic Documents, never before published; to which is added, his British Catalogue of Stars. By Francis Baily, Esq.: Lond. 1835. 4to. Pp. 671. A Supplement appeared in January 1837, in reply to criticisms by the friends of Newton.


Baily's Flamsteed, pref., pp. xix. xx.


Mr. Baily was able to publish only eleven of Flamsteed's letters to Newton, and these not correct copies of the originals.


Eighteen letters from William Molyneux to Flamsteed, written in the most affectionate terms, and dated between September 17, 1681, and May 17, 1690, inclusive, were published in the General Dictionary, Art. MOLYNEUX, vol. vii. p. 613.


These propositions are referred to in his letter to Flamsteed, May 7, 1690.


Molyneux's Dioptrics was published in 1692, and the Life, addressed to his brother, in 1694. He died in 1698, at the age of forty-two. See An Account of the Family and Descendants of Sir Thomas Molyneux, Bart. Evesham, 1820. 4to.


See Vol. i. p. 301.


See Vol. i. p. 146.


King's Life of Locke, vol. ii. p. 38.


Biog. Brit. vol. ii. p. 256, or, The Works of GEORGE BERKELEY, D.D., Bishop of Cloyne, p. viii. Lond. 1837.


Quarterly Review, vol. lv. p. 112.


We recommend to the reader the able Defence of Halley against the Charge of Religious Infidelity, by the Rev. S. J. RIGAUD, M.A., of Ipswich, Oxford, 1844. Professor Rigaud, the author's distinguished father, a man of genuine piety, entertained the same opinion of Halley.


We owe to Halley the discovery of the secular equation of the moon.


"The following curious memorandum," says Mr. Rigaud, "is written by Dr. Gregory in the margin of his annotations on the Principia, p. 162. The subject to which he has annexed it, is the mention of Flamsteed's lunar tables, derived from the hypothesis of Horrox, (Schol. p. 462, first edit. of Principia), 'Newtonus mihi sæpe dixit, nominatim Decembri 1698, Londini, tabulas hasce fuisse ab Ed. Halleio primum factas et supputatas, et cum Joh. Flamstedio communicatas, et ab illo, inscio Halleio, editas, et propter hoc factum æternas natas esse inter Halleium et Flamstedium rixas. Newtonus dixit se vidisse autographum Halleii" — Defence of Halley, p. 20.


Flamsteed, who makes this statement in his autobiography, concludes it by saying, "All this he (Newton) approved, and by a letter of his dated . . . . . confessed. Nevertheless he imparted what he derived from them both to Dr. Gregory and Dr. Halley, contra datam fidem. The first of these conditions I believe he kept. The latter he has forgot or broke."


In defence of Newton, we may state, that in a few days after Flamsteed exacted the first of these conditions, he not only showed the same observations to Halley, but suffered him to take notes of part of them. With regard to the second condition, which he is said to have broken, we shall presently see, from an unpublished letter of Flamsteed, that he asks Newton certain questions about the moon's theory, and that Newton imparted to him his remarkable equation of the menstrual parallax. We shall find also that he imparted to him, in return for his observations, his theory and table of refractions, one of the finest productions of his genius, and of essential value to Flamsteed in the reduction of his observations, and subsequently his valuable tables of the moon's parallax, and the equations of the moon's apogee and the eccentricity of her orbit. It appears, too, from a letter of Newton of the 17th November 1694, that he asks Flamsteed to have but a little patience, and he will be the first man to whom it will be imparted, when the theory is fit to be communicated without danger of error. In consequence of the delay in getting Flamsteed's observations, he was not able to proceed any farther with the lunar theory, and his appointment to the Mint necessarily interfered with his scientific researches. His connexion with Flamsteed had ceased for many years, and therefore the brief notice of the lunar theory which he communicated to Gregory in June 1702, could not be considered as a breach of the condition under which Flamsteed brought him.

That the reader may be sufficiently aware of the rash charges which Flamsteed never scrupled to make against those who displeased him, we quote the following example contained in his own letters, which Mr. Rigaud has observed. "In 1705, Abraham Sharpe communicated to the Royal Society his quadrature of the circle; and Flamsteed writes him an account in which Halley is accused of acting most unfairly, and with a view to his own credit, about printing the papers. This was on the 20th August, and on the 11th of the following month, Flamsteed found himself obliged to retract what he said on the subject, and yet in April 1715 he had forgotten everything but what accorded with his hostile feeling, and writes to the very same man to say, 'you remember how he served you about the quadrature of the circle; after such usage, you ought to be very cautious how you treat him.'" — Defence of Halley, pp. 20, 21, and Baily's Flamsteed, pp. 244, 246, and 313.


Newton seems to have been unwell at the time of his visit to Greenwich, for Flamsteed begins this unpublished letter, dated September 7, 1694, with the intimation that he had sent him a receipt which Mr. Stanhope's sister makes use of with good effect, and wished he might find the same benefit from it. In his reply, Newton "thanks him heartily for the receipt."


Dated October 7, 1694.

The coefficient for this equation is the Sine of the sun's parallax divided by that of the moon's.

[24] Editorial Note: This Note Empty


The original of this letter differs from that published by Mr. Baily in two points. The "empirical small table of the differences of refraction of the sun and Venus in height" has been omitted in the published copy, and also the following postscript. "Mr. Halley is busy about the moon, has promised me his corrections, intends to print something about her system ere long, and affirms the moon's motion different in the times of Albategni from what it is now." I have given this table in the APPENDIX, No. XIII., in order to justify the references to it in the letters of October 11 and 24, 1694.


October 24, 1694.


October 25, 1694, unpublished


See Principia, 2d Edit. p. 481.


November 3, 1694, unpublished.


In this letter Flamsteed says, that the parallactic equation does not exceed a single vibration of the pendulum, and cannot be determined by the largest instruments.


This letter of Flamsteed's, as published by Mr. Baily, differs entirely from the letter actually sent to Newton, and must have been a scroll, which he greatly altered and enlarged. We cannot, therefore, place confidence in the abstracts of his letters to Newton, as printed by Mr. Baily. The date of the letter is December 16th, not the 6th. In the original copy of this letter, and also in the scroll, Flamsteed introduces a new charge against Halley in the following words: — "I desired you in my last to let me know if you had not been presented some years agone with a geometrical tract of Viviani's, in quarto, Latin. You have given me no answer. Pray, be free with me, and let me have one, it will much oblige." In his letter of the 27th, he had said, — "I desire you to let me know whether Mr. Halley did not, five or six years ago, present you with a geometrical piece of Viviani's in quarto?" Newton made no reply to these requests. On the 31st December, Flamsteed thus recurs to the subject: — "I must beg your pardon for having urged you twice about Viviani's book. I shall tell you the occasion, and give you no farther trouble. Mr. Rook being in Italy, received one of them directed to me by the author's own hand, which he sent to E. H. (Edmund Halley) with other things, who, I am told, presented it to you; and himself denies not that he sent it you. Now, I am not concerned for the book at all. If you had one from him, keep it either as his gift or mine; but because I have great reason to suspect a book of much greater value, directed to me, has been disposed of for advantage by a friend and acquaintance of his this last summer, and if the first had been brought to light, the latter might have been made evident; but I desire to concern you no farther with it, and therefore shall move you no more, nor expect any answer in this particular, being ever desirous to make my friends as easy as I can." To these applications Newton replied on the 26th Jan. 16945, — "About three or four months before Dr. Gregory was made Professor of Astronomy at Oxford, an Oxford gentleman, a student in mathematics, (I think his name was Rook,) called on me on his way from London, and showed me a new book published by Viviani. He offered to leave it with me to peruse; whereupon I turned over the leaves, and then returned it to him again, and he took it away with him, I think, to Oxford; and I saw it no more. I forbore to answer your first inquiries about it, because I feared it might tend to widen the breach between you and Mr. Halley, which I would rather reconcile if it were in my power. And now I hope that what I have told you will not be made use of to that purpose, lest it should also do me an injury." — See Baily's Flamsteed, pp. 144, 145, 148, 149. "I am very well satisfied," replies Flamsteed on the 29th January, "in what you tell me about Viviani's book; and you may conclude what you are to think of Mr. Halley from this, that he told me before a club of the Society that you had it. I find you understand him not so well as I do. I have had some years' experience of him, and a very fresh instance of his inge <173> nuity, with which I shall not trouble you. 'Tis enough that I suffer by him. I would not that my friends should, and therefore shall say no more, but that there needs nothing but that he show himself an honest man to make him and me perfect friends; so that if he were candid, there is nobody living in whose acquaintance I would take more pleasure; but his conversation is such that no modest man can bear it, and no good man but will shun it." The four obnoxious paragraphs in the draught of this letter, at the bottom of p. 150 of Baily's Flamsteed, do not exist in the original sent to Newton!


December 20, 1694.


See Biot's interesting observations on this theorem, and his admirable and elaborate Analysis of Newton's Tables of Refraction, with an indication of the Numerical Processes by which he computed them, in the Journal des Savans, 1836, pp. 642, 735.


January 15, 1695.


January 18, 1695.


January 26, 1695.


February 16, 1695.


Journal des Savans, November 1836, p. 655.


July 9, 1695


These passages were underlined by Flamsteed.


July 2, 1695.


The italics are in the original.


"Machin told me," says Conduitt, "that Flamsteed said 'Sir Isaac worked with the ore he had dug,' to which Sir Isaac replied, 'if he dug the ore, I made the gold ring.'" — Conduitt's MSS


July 23d, 1695.


In this letter, Flamsteed "presents him, before he demands it," with "a nonagesimary table" for every degree of right ascension, "as I would not have you want any thing that lies in my power to save you the trouble of calculation," and he closes his letter thus: "By frequent trials and alterations of his contrivances, Kepler found out the true theory of the planetary motions. You must not be ashamed to own that you follow his example. When the inequalities are found, you will more easily find the reason of them than he could do when but little of the doctrine of gravity was known."


July 27th, 1695.


In the copy of this letter in the British Museum, the words two shillings appear here with the following note. "Mr. Flamsteed altered it so for the word guineas, which is in the original, as is evident from the erasure." Professor Rigaud, at Mr. Baily's desire, examined the original letter, and found the words two guineas if you please to call for it crossed out with the pen, but no substitution of guineas for shillings. Mr. Edleston, however, who has examined the original, observes that all the words following "pay him" (in the passage given in the text in italics) are crossed out in the manuscript, and the word "guineas" altered into "shillings" apparently by Flamsteed. The words after "for them" to the end of the passage are conjectural, the original writing being most skilfully blotted out. . . . What motive Flamsteed could have had for disguising any part of the above sentence, I do not pretend to divine. It is curious that Mr. Rigaud, who examined the manuscript in reference to this very point, should have overlooked the original "guineas." — Edleston's Correspondence, &c., p. lxviii. note 125


August 4, 1695.


Not on the 17th, as stated in Baily's Flamsteed, p. 160. Flamsteed's notes of his answer to Newton's letter, as usual, misrepresents its contents.


In this letter, Flamsteed tells him that "some friends of his who live at a distance in the country, have made new tables for representing the motions of the two superior planets, Jupiter and Saturn," within ten or twelve minutes of observation. I find other four letters from Flamsteed to Newton, dated September 4, December 10, 1697, December 29, 1698, and January 9, 1699. The last of these letters is a long and curious reply to Newton on the subject of his letter of the 6th January 1699, blaming Flamsteed for mentioning his theory of the moon in a letter on the parallax of the fixed stars, sent to Dr. Wallis to be printed. The consideration of these letters belongs to another Chapter.


We have already shown that this accident happened before 1684.


Newton has made no such avowal. Biot quotes, in support of his allegation, Newton's declaration to Locke, that "he had not his former consistency of mind," — a mere temporary state, from which he completely recovered.


Journal des Savans, November 1836, p. 657.

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