WHEN Sir Isaac Newton was one day conversing with the Princess of Wales, on some points of ancient history, in reference to the education of the royal family, he was led to mention to her, and to explain, a new system of chronology which he composed during his residence at Cambridge, where he was in the habit, as he expresses it, "of refreshing himself with history and chronology when he was weary of other studies." The Princess was so much pleased with the ingenuity of his system, that she sent a message by the Abbé Conti, when in England, desiring Sir Isaac to speak with her, and on this occasion she requested a copy of the work which contained his system of chronology. Sir Isaac informed her that it existed only in separate papers, which were not only in a <302> state of confusion, but contained a very imperfect view of the subject; and he promised in a few days to draw up an abstract of it for her Royal Highness's perusal, and on the condition that it should not be communicated to any other person.[1] Some time after the Princess received the manuscript, she requested that the Abbé Conti might be permitted to have a copy of it. Sir Isaac granted her request, and the Abbé was distinctly informed that the manuscript was given to him at the request of the Princess, and with Sir Isaac's leave, and that he was to keep it a secret. It was entitled "A Short Chronicle from the First Memory of Things in Europe to the Conquest of Persia by Alexander the Great." It occupies only twenty-four quarto pages, with an introduction of four pages, in which Sir Isaac states that he "does not pretend to be exact to a year, and that there may be errors of five or ten years, and sometimes twenty, but not much above."

During his residence in England, the Abbé Conti kept his promise of secrecy, but he no sooner reached Paris than he communicated the manuscript to several persons, and among others to M. Freret, a learned antiquary, who not only translated it into French, but added observations of his own, for the purpose of refuting some of its leading <303> results. Sir Isaac knew nothing of this transaction till the month of May 1724, when he received a respectful letter from G. Cavelier, a bookseller in Paris, informing him that a small manuscript had fallen into his hands, which he was assured came from his pen, and that as his name was very highly esteemed throughout Europe, he wished to print it. He had learned, however, that it contained some errors, and as Sir Isaac would probably not wish it to appear under his name, he begged, as the manuscript which he had was of little value, that he would give him a correct copy of His Chronology. He added, that several persons who had defective copies would be glad to have correct ones, and as he was a bookseller who desired only to publish good articles, he was persuaded there could be nothing better than what came from his pen.

Sir Isaac took no notice of this letter, the object of which he probably thought was to get money for the manuscript, for he could hardly suppose that a mere pamphlet on a subject by no means popular, and supposed to contain errors, would repay the expenses of publication. After waiting nearly ten months for an answer, Cavelier addressed another letter to Newton, dated March 20, 1725, in which he asks him if he has additions or corrections to make, as some errors have been committed by the translator. He requests an immediate answer, and adds, that if he does not receive one, he will consider his silence as his consent to the publication of the work, "with remarks."[2]

As Sir Isaac paid no attention to this second letter, Cavelier requested a friend in London to procure an answer, which he at last received in the following terms: —

"I remember that I wrote a chronological index for a particular friend, on condition that it should not be com <304> municated. As I have not seen the MS. which you have under my name, I know not whether it be the same. That which I wrote was not at all done with design to publish it. I intend not to meddle with that which hath been given you under my name, nor to give any consent to the publishing of it. — I am, your very humble servant,


"London, May 27, 1725. St. Vet."

Before Cavelier received this letter the work was printed,[3] and a copy of it was sent to Newton as a present, on the llth November 1725.[4] The pamphlet was accom <305> panied by Freret's observations, and, in an advertisement prefixed to it, Cavelier defends himself for printing it against the author's wishes, on the ground that he had written three letters to obtain his permission, and, in order to insure an answer, had intimated to him that he would take his silence for consent. When Sir Isaac received this work, he drew up a paper entitled, Remarks on the Ohservations made on a Chronological Index of Sir Isaac Newton, translated into French hy the Observator, and published at Paris, which was printed in the Philosophical Transactions.[5] In this paper Sir Isaac gives a history of the transaction, charges the Abbé Conti with a breach of promise,[6] and blames the publisher for having asked his leave to print the translation without sending him a copy for his perusal, — without acquainting him with the name of the translator, — and without announcing his intention of printing along with it a refutation of the original. The observations made by the translator against the conclusions deduced by the author, were founded on an imperfect knowledge of Sir Isaac's system; and they are so specious, that Halley himself confesses that he was at first prejudiced in favour of the Observations, taking the calculations for granted, and not having seen Sir Isaac's work.

To all the observations of M. Freret Sir Isaac returned a triumphant answer. This celebrated writer had ventured to assert, "that he believed he had stated enough concerning the epoch of the Argonauts, and the length of generations, to make people cautious about the rest; <306> for these are the two foundations of all this new system of chronology." He founds his arguments against the epochs of the Argonauts, as fixed by our author, on the supposition that Sir Isaac places the vernal equinox at the time of the Argonautic expedition in the middle of the sign of Aries, whereas Sir Isaac places it in the middle of the constellation, — a point corresponding with the middle of the back of Aries, or 8° from the first star of Aries. This position of the colure is assigned on the authority of Eudoxus, as given by Hipparchus, who says that the colure passed over the back of Aries. Setting out with this mistake, M. Freret concludes that the Argonautic expedition took place 532 years earlier than Sir Isaac made it. His second objection to the new system relates to the length of generations, which he says is made only eighteen or twenty years. Sir Isaac, on the contrary, reckons a generation at thirty-three years, or three generations at 100; and it was the lengths of the reigns of kings that he made eighteen or twenty years. This deduction he founds on the reigns of sixty-four French kings. Now, the ancient Greeks and Egyptians reckoned the length of a reign equal to that of a generation; and it was by correcting this mistake, and adopting a measure founded on fact, that Sir Isaac placed the Argonautic expedition forty-four years after the death of Solomon, and fixed some of the other points of his system.

Sir Isaac concludes his remarks with the following passage: — "Abbé Conti[7] came into England in spring <307> 1715, and, while he staid in England, he pretended to be my friend, but assisted Mr. Leibnitz in engaging me in new disputes. The part he acted here may be understood by the character given of him in the Acta Eruditorum for 1721. . . . . And how Mr. Leibnitz, by his mediation, endeavoured to engage me against my will in new disputes about occult qualities, universal gravity, the sensorium of God, space, time, vacuum, atoms, the perfection of the world, supramundane intelligence, and mathematical problems, is mentioned in the second edition of the Commercium Epistolicum. And what he hath been doing in Italy may be understood by the disputes raised there by one of his friends,[8] who denies many of my optical experiments, though they have been all tried in France with success; but I hope that these things, and the perpetual motion, will be the last efforts of this kind — will be the last efforts of those friends of Mr. Leibnitz to embroil me."[9]

This answer of Sir Isaac's to the objections of Freret called into the field a fresh antagonist, Father Souciet, who published five Dissertations on the new chronology. These Dissertations were written in a tone so highly <308> reprehensible, that Mr. Conduitt being apprehensive that the manner in which his system was attacked would affect Sir Isaac more than the arguments themselves, prevailed upon a friend to draw up, for his perusal, an abstract of Souciet's objections, stripped of the "extraordinary ornaments with which they were clothed." The perusal of these objections had no other effect upon him than to convince him of the ignorance of their author; and he was induced to read the entire work, which produced no change in his opinion.

In consequence of these discussions, Sir Isaac was prevailed upon to prepare his larger work for the press. After the publication of Freret's Observations, he had resolved to print it "as privately as possible, and keep the copies in his own possession," but it was not ready till nearly the time of his death. It did not therefore appear till 1728, when it was published by Mr. Conduitt under the title of the Chronology of Ancient Kingdoms amended, to which is prefixed a short Chronicle, from the First Memory of Things in Europe to the Conquest of Persia hy Alexander the Great.[10] It consists of six chapters: — 1. On the Chronology of the Greeks;[11] 2. Of the Empire of Egypt; 3. Of the Assyrian Empire; 4. Of the two contemporaiy Empires of the Babylonians and Medes; 5. A Description of the Temple of Solomon; 6. Of the Empire of the Persians. The sixth chapter was not copied out with the other five, which makes it doubtful whether or not it was intended for publication; but as it was found among his papers, and appeared to be a continuation of the same <309> work, it was thought right to add it to the other five chapters.[12]

After the death of Newton, Dr. Halley, who had not yet seen the larger work, felt himself called upon, both as Astronomer-Royal and as the friend of the author, to reply to the first and last dissertations of Father Souciet, which were chiefly astronomical; and in two papers[13] he has done this in a most convincing and learned argument.

Among the supporters of the views of Newton, we may enumerate Dr. Reid, Nauze, and some other writers; and among its opponents, M. Freret, who left behind him a posthumous work on the subject,[14] M. Fourmond, Mr. A. Bedford, Dr. Shuckford, Dr. Middleton, Whiston,[15] and the late M. Delambre. The object of M. Fourmond is to show the uncertainty of the astronomical argument, arising on the one hand from the vague account of the ancient sphere as given by Hipparchus; and, on the other, from the extreme rudeness of ancient astronomical observations. Delambre has taken a similar view of the subject: he regards the observations of ancient astronomers as too incorrect to form the basis of a system of chronology; and he maintains, that if we admit the accuracy of the details in the sphere of Eudoxus, and suppose them all to belong to the same epoch, all the stars which it contains <310> ought at that epoch to be found in the place where they are marked, and we might thence verify the accuracy, and ascertain the state of the observations. It follows, however, from such an examination, that the sphere would indicate almost as many different epochs as it contains stars. Some of them even had not, in the time of Eudoxus, arrived at the position which had been for a long time attributed to them, and will not even reach it for 300 years to come, and on this account he considers it impossible to deduce any chronological conclusions from such a rude mass of errors.

But, however well founded these observations may be, we agree in opinion with M. Daunou,[16] "that they are not sufficient to establish a new system, and we must regard the system of Newton as a great fact in the history of chronological science, and as confirming the observation of Varro, that the stage of history does not commence till the first Olympiad."

Among the chronological writings of Sir Isaac Newton, we must enumerate his Letter to a person of distinction who had desired his opinion of the learned Bishop Lloyd's Hypothesis concerning the Form of the most Ancient Year. This hypothesis was sent by the Bishop of Worcester to Dr. Prideaux. Sir Isaac remarks, that it is filled with many excellent observations on the ancient year; but he does not "find it proved that any ancient nations used a year of twelve months and 360 days without correcting it from time to time by the luminaries to make the months keep to the course of the moon, and the year to the course of the sun, and returns of the seasons and fruits of the earth." After examining the years of all the nations of <311> antiquity, he concludes, "that no other years are to be met with among the ancients but such as were either lunisolar, or solar or lunar, or the calendars of these years." A practical year, he adds, of 360 days, is none of these. The beginning of such a year would have run round the four seasons in seventy years, and such a notable revolution would have been mentioned in history, and is not to be asserted without proving it.[17]

When the public attention was called to the reformation of the Kalendar, Sir Isaac seems to have been consulted on the subject. Among his papers he has left two copies, one distinctly written out as if for publication, entitled Considerations about rectifying the Julian Kalendar.[18] After giving an account of the Egyptian Kalendar — the improvements introduced by Julius Cæsar and the Roman senate, and the correction made by Gregory XIII., — he describes what in another manuscript he calls the best form of the solar year. "The best form of the solar year," he says, "is to divide it by the four cardinal periods of the equinoxes and solstices, so that the quarters of the year may begin at the equinoxes and solstices as they ought to do, and then to divide every quarter into three equal months, which will be done by making the six winter months to consist of 30 days each, and the six summer months of 31 days each, excepting one of them, suppose the last, which in the leap years shall have 31 <312> days, in the other years only 30 days. At the end of every 100 years, omit the intercalary day in the leap year, excepting at the end of every 500 years. For this rule is exacter than the Gregorian, of omitting it at the end of every 100 years, excepting at the end of every 400 years, and thus reckoning by 500ds and thousands of years is rounder than the other by 400, 800, and 1200ds. And this I take to be the simplest, and in all respects the best form of the civil year that can be thought of."

In the paper entitled Considerations, &c., in which the above form of the civil year is stated less fully, he goes on to consider the best method of introducing a change of style.

"But without the consent of a good part of Europe," he says, "I do not think it advisable to alter the number of days in the month. The question is now whether the old style should be retained in conformity with antiquity, or the new received in conformity with the nations abroad. I press neither opinion; but whenever the latter shall be resolved upon, I believe the best way may be, to receive the new style without the Gregorian Kalendar by an Act of Parliament, to some such purpose as that which follows."[19]


In order to enjoy the conversation of the most distinguished literary men at that time in England, the "Princess of Wales appointed a particular day in the week, when they were invited to attend her Royal Highness in the evening; a practice which she continued after her accession to the throne. Of this company were Drs. Clarke, Hoadley, Berkeley, and Sherlock. Clarke and Berkeley were generally considered as principals in the debates that arose upon those occasions, and Hoadley adhered to the former as Sherlock did to the latter. Hoadley was no friend to Berkeley: he affected to consider his philosophy and his Bermuda project as the reveries of a visionary. Sherlock, (who was afterwards Bishop of London,) on the other hand, warmly espoused his cause, and particularly when the 'Minute Philosopher' came out, he carried a copy of it to the Queen, and left it to her Majesty to determine whether such a work could be the production of a disordered understanding." — Works of George Berkeley, D.D., Bishop of Cloyne, p. vii. Lond. 1837.


These two letters of Cavelier have been preserved by Sir Isaac.


It was entitled Abrégé de Chronologie de M. Le Chevalier Newton, fait par lui-même, et traduit sur le manuscript Anglois. Paris, 1725.


The existence of this manuscript in Paris was generally known, and was the subject of conversation before the date of Cavelier's first letter to Newton, (May 11, 1724), as appears from the following extract of a letter from M. Montmort (or perhaps from Conti) to Brook Taylor, dated Paris, January 15, 1724: —

"On m'a dit aussi que Mr. Newton imprime la Chronologie Raisonnée. Tout le monde l'attend avec bien de l'impatience. Faites luy mes complimens, je vous en prie; voicy une petit Sonnet que vous luy communiquerez; j'espère qu'il en sera content; car il verra l'attraction désigné par l'amour, qui règle le sistême de M. Descartes désigné par Phaeton. Dans le Mémoires de Leipsique, il aura vu si je suis du parti des Allemands.

'Lasciar mi il curro Governar del giorno,'

Disse à Febo l'Amor, 'e tosto sia

Rectificata in Ciel l'alta armonia

Che Fetonte turbó con suo gran scorno

Io diedi sede al cancro ed al capricorno

Ed al corpo lunar l'obliqua via

Io sterno al par del Caos; ed Io con lumeor

Forzo al mondo l'equilibro; ed Io l'adorno.

Disse:' e le Briglie imperioso stese

E corresse l'Aurora, ed agli infinite

Fonti del lume il corso antico rese

Ritornó i Pianet' ai primi siti

Il Solar Orbe a perni scai s'apese

E tal fu poi qual' O Newton l'additi.


Contemplatio Philosophica, and Life of Brook Taylor. Lond. 1793, p. 141.

M. Conti is supposed to be the Abbot who corresponded with Lady Mary Wortley Montague. See her Letters and Works, vol. i. p. 358, and vol. ii. pp. 11, 21, 119, and 128.


Phil. Trans. 1725, Vol. xxxiii. No. 389, p. 315. I have found seven distinctly written copies of this paper in Sir Isaac's handwriting.


Conti is said to have defended himself with much moderation, and with many expressions of esteem for Newton. See Biog. Univ., tom. ix. p. 517.


In the passage from the Acta Eruditorum, Conti is described as carrying letters of Newton's to Leibnitz, and communicating Leibnitz's letters to Newton. Conti was a very excellent and accomplished person, distinguished as a poet and a man of very considerable acquirements. He was a great favourite of the King, and acted as interpreter when Dr. Clarke, who could speak only Latin and English, was explaining to his Majesty the discoveries of Newton. It was at the King's request that he <307> interfered in the dispute between Newton and Leibnitz, and we see no reason to blame him for the part which he acted in that matter.


Signior Rizzetti, who afterwards published his attack upon Newton in a book entitled De Luminis Affectionibus Specimen Physico-Mathematicum. Venet. 1727. — See Desaguliers' Defence of Newton in the Phil. Trans. 1728, p. 596.


The words in italics are in another copy. I find also from one of these copies that Conti is charged with "sending Mr. Stirling to Italy, a person then unknown to me, to be ready to defend me there, if I would have contributed to his maintenance;" and in another, Conti is said to have "softened the business, by lately writing a poem upon him, and in the colour of a friend." This poem is probably that mentioned by Bolingbroke in a letter to Brook Taylor, Dec. 26, 1723. "He has begun a philosophical poem which will be finished, I believe, long before the Anti-Lucretius of the Cardinal de Polignac. Sir I. Newton's system will make the principal beauty in it. He recited the Exorde to me, which I thought very fine. I need not tell you that lie writes in Italian." — Life of Brook Taylor, p. 136.


The work is dedicated to the Queen by Mr. Conduitt, in an address of twelve quarto pages, in composing which he sought the assistance of Pope. We have given Pope's letter, containing his criticisms, in the APPENDIX, No. XXVII.


According to Whiston, Sir Isaac wrote out eighteen copies of this chapter with his own hand, differing little from one another. — Whiston's Life, p. 39.


This work forms the first article in the fifth volume of Dr. Horsley's edition of Newton's works, and is accompanied with copious notes. The next article in the volume is entitled, A Short Chronicle from a MS., the property of the Reverend Dr. Ekins, Dean of Carlisle," which is nothing more than an abstract of the chronology already printed in the same volume. We cannot even conjecture the reasons for publishing it, especially as it is less perfect than the abstract, two or three dates being wanting.


Phil. Trans. 1727, vol. xxxiv. pp. 205, 296.


Défense de la Chronologie contre le Systême de M. Newton. Paris, 1758, 4to.


Collection of Authentic Records, Part II. No. 24. 1727.


See an excellent view of this controversy in an able note by M. Daunou, attached to Biot's Life of Newton in the Biog. Universelle, tom. xxxi. p. 180.


This letter was first published without any date in the Gentleman's Magazine for 1755, vol. xxv. p. 3. I have found two copies of it among Sir Isaac's papers. Mr. Edleston informs us that the original is in the British Museum, presented by Mrs. Sharp. I have found also two copies of the communication he made to the Bishop of Worcester, which is published by Mr. Edleston in his Correspondence, &c. Appendix, p. 314. One of these copies is much fuller than that which is printed by Mr. Edleston.


I infer that this paper was written in 1699, from the statement in it that Pope Gregory's corrections "were made 118 years ago."


I find two copies of another paper in Latin, entitled Regulæ pro determinatione Paschœ. The subject of the Kalendar is touched upon in Newton's Chronology, p. 71, and in his Observations on the Prophecies of Daniel, p. 137, note.

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