Nicolas Fatio de Duillier
Nicolas Fatio de Duillier FRS (also spelled Faccio or Facio; 16 February 1664 – 12 May 1753) was a Swiss-born mathematician, natural philosopher, inventor, and religious campaigner. He spent much of his adult life in England and Holland. Fatio is known for his correct explanation of the astronomical phenomenon of zodiacal light, for first proposing the "push" or "shadow" theory of gravitation, for his close association with both Christiaan Huygens and Isaac Newton, and for his role in the Newton v. Leibniz calculus controversy. He also invented and developed the first method for fabricating jewel bearings for mechanical watches and clocks.
|Nicolas Fatio de Duillier|
26 February 1664|
Basel, Swiss Confederacy
12 May 1753 (aged 89)|
Madresfield, Great Britain
|Known for||zodiacal light, Le Sage's theory of gravitation, jewel bearing|
|Fields||Mathematics, astronomy, watchmaking|
|Influences||Giovanni Domenico Cassini, Christiaan Huygens, Isaac Newton|
|Influenced||Georges-Louis Le Sage|
Elected fellow of the Royal Society of London at the age of 24, Fatio never achieved the position and reputation that his early achievements and connections had promised. In 1706 he became involved with a millenarian religious sect, known in London as the "French prophets", and the following year he was sentenced to the pillory for sedition over his role in the publication of the prophecies of Élie Marion, the leader of that sect. Fatio travelled with the French prophets as a missionary, going as far as Smyrna before returning to Holland in 1713, later settling in England. His religious views harmed his intellectual reputation, but Fatio continued to pursue technological, scientific, and theological researches until his death at the age of 89.
Nicolas Fatio was born in Basel, Switzerland, in 1664, into a family that originated in Italy and settled in Switzerland following the Protestant Reformation. One of his cousins was the ill-fated political reformer Pierre Fatio. Nicolas was the seventh of nine children (two brothers and seven sisters) of Jean-Baptiste and Cathérine Fatio, née Barbaud. Jean-Baptiste had inherited a significant fortune, derived from his father's interests in iron and silver mining, and in 1672 he moved the family to an estate that he had purchased in Duillier, some twenty kilometres from the town of Geneva. Jean-Baptiste, a devout Calvinist, wished Nicolas to become a pastor, whereas Cathérine, a Lutheran, wanted him to find a place in the court of a Protestant German prince. Instead, the young Nicolas pursued a scientific career.
Nicolas Fatio's elder brother, Jean-Christophe Fatio, was elected a Fellow of the Royal Society on 3 April 1706. He published in the Philosophical Transactions a description of the solar eclipse that he had observed in Geneva on 12 May of that year. He died at Geneva on 18 October 1720. By his wife Catherine, daughter of Jean Gassand of Forealquiere in Provence, whom he married in 1709, he left no issue. Her will was proved at London in March 1752,
Education and patronageEdit
Nicolas Fatio received his elementary schooling at the Collège de Genève, proceeding in 1678 to the Académie de Genève (now the University of Geneva), where he remained until 1680. At the Academy he came under the influence of the rector, Jean-Robert Chouet, a prominent Cartesian. Before he was eighteen, Fatio wrote to the astronomer Giovanni Domenico Cassini, director of the Paris Observatory, suggesting a new method of determining the distances to the Sun and Moon from the Earth, as well as an explanation of the form of the rings of Saturn. With Chouet's support, Fatio travelled to Paris in the spring of 1682 and was warmly received by Cassini.
That same year, Cassini presented his findings on the astronomical phenomenon of zodiacal light. Fatio repeated Cassini's observations in Geneva in 1684, and in 1685 he offered an important development of Cassini's theory, which was communicated by Chouet in the March 1685 number of Nouvelles de la république des lettres. Fatio's own Lettre à M. Cassini touchant une lumière extraordinaire qui paroît dans le Ciel depuis quelques années ("Letter to Mr. Cassini concerning the extraordinary light that has appeared in the Heavens for some years") was published in Amsterdam in 1686. There Fatio correctly explained the zodiacal light as sunlight scattered by an interplanetary dust cloud (the "zodiacal cloud") that straddles the ecliptic plane.
Fatio then studied the dilatation and contraction of the pupil of the eye. He described the fibres of the anterior uvea and the choroid in a letter to Edme Mariotte, dated 13 April 1684. That same year he published an article in the Journal des sçavans on how to improve the fabrication of lenses for the objectives of telescopes.
Also in 1684, Fatio became acquainted with the Piedmontese Count Fenil, who, having offended the Duke of Savoy and the King of France, had taken refuge in the house of Fatio's maternal grandfather in Alsace, and then at Duillier. Fenil confided to Fatio his plan to stage a raid on the beach at Scheveningen to kidnap the Dutch Prince William of Orange. Fenil showed Fatio a letter from the Marquis de Louvois, the French Secretary of State, approving of the kidnapping, offering the king's pardon, and enclosing an order for money. Fatio betrayed Fenil's plot to Gilbert Burnet, whom he then accompanied to Holland in 1686 to warn Prince William.
Career in Holland and EnglandEdit
In Holland, Fatio met Christiaan Huygens, with whom he began to collaborate on mathematical problems concerning the new infinitesimal calculus. Encouraged by Huygens, Fatio compiled a list of corrections to the published works on differentiation by Ehrenfried Walther von Tschirnhaus. The Dutch authorities wished to reward Fatio, whose mathematical abilities Huygens vouched for, with a professorship. While those plans were delayed, Fatio received permission to visit England in the spring of 1687. In England, Fatio hoped to procure the patronage of Robert Boyle.
In London in 1687, Fatio made the acquaintance of John Wallis, John Locke, Richard Hampden, and his son John Hampden, among other important figures connected with the Whig party. Fatio worked out new solutions of the "inverse tangent problem" (i.e., of ordinary differential equations) and was introduced to the Royal Society by Henri Justel. He began to attend Society's meetings in June of that year, thus learning of the upcoming publication of Newton's Principia. In the winter of 1687 Fatio went to Oxford, where he collaborated with Edward Bernard, the Savilian Professor of Astronomy, in an investigation into the units of measurement used in the ancient world.
Participation in the Royal SocietyEdit
Aged only 24, Fatio was elected fellow of the Royal Society on 2 May 1688. That year, Fatio gave an account of Huygens's mechanical explanation of gravitation before the Royal Society, in which he tried to connect Huygens' theory with Isaac Newton's work on universal gravitation. Fatio's personal prospects seemed to brighten even further as a result of the Glorious Revolution of 1688–9, which marked the ascendancy of the Whigs and culminated with Parliament deposing the Catholic King James II and giving the English throne jointly to James's Protestant daughter Mary and to her husband, the Dutch Prince William of Orange. Fatio also had an opportunity to enhance his intellectual reputation during Huygen's visit to London in the summer of 1698.
Fatio encountered Newton, probably for the first time, at a meeting of the Royal Society on 12 June 1689. Newton and Fatio soon became friends and Newton even suggested that the two share rooms in London while Newton attended the post-Revolutionary session of Parliament, to which he had been elected as member for the University of Cambridge. In 1690, Fatio wrote to Huygens outlining his own understanding of the physical cause of gravity, which later became known as "Le Sage's theory of gravitation". Soon after that, he read his letter to Huygens before the Royal Society. Fatio's theory, on which he continued to work until his death, is based on minute particles streaming through space and pushing upon gross bodies, an idea that Fatio probably derived in part from his explanation of zodiacal light as sunlight scattered by a cloud of fine dust surrounding the Sun.
Fatio went to the Netherlands in the spring of 1690 as tutor to two of John Hampden's nephews. In The Hague, Fatio shared with Huygens a list that he had compiled of errata to Newton's Principia. Fatio and Huygens collaborated on problems relating to differential equations, gravity, and optics. At this time, Huygens shared with Gottfried Leibniz some of Fatio's work on differential equations. Fatio returned to London in September 1691, following the death of one of his pupils. He vied unsuccessfully for the Savilian Professorship of Astronomy at Oxford, a post that had been left vacant by the death of his friend Edward Bernard.
Fatio convinced Newton to write a new treatise on a general method of integration, De quadratura curvarum. Initially, he also expected to collaborate with Newton on an entirely new edition of the Principia that would include Fatio's mechanical explanation of gravity. By the end of 1691, Fatio realised that Newton would not proceed with that project, but he still hoped to collaborate with Newton on corrections to the text of the Principia. In a letter to Huygens, Fatio wrote, concerning those corrections, "I may possibly undertake it myself, as I know no one who so well and thoroughly understands a good part of this book as I do."
Fatio refused Newton's offer to reside in Cambridge as his assistant, seeking instead academic preferment in the Netherlands. By the summer of 1694 he was employed as a tutor to Wriothesley Russell, the heir of the Duke of Bedford, a position for which he had been recommended by Locke. Fatio accompanied his pupil to Oxford and, during 1697–8, to Holland.
Role in Newton's quarrel with LeibnizEdit
As a result of reading Newton's De quadratura curvarum, Fatio became convinced that Newton had for some time had a complete understanding of the differential and integral calculus, rendering Fatio's own discoveries superfluous. He reported as much to Huygens in 1692. In 1696, Johann Bernoulli, a close ally of Leibniz, posed the brachistochrone problem as a challenge to the mathematicians who claimed to understand the new calculus. The problem was solved by Leibniz, Tschirnhaus, L'Hôpital, Jacob Bernoulli, and Newton. In 1699, Fatio published Lineæ brevissimæ descensus investigatio geometrica duplex, cui addita est investigatio geometrica solidi rotundi in quo minima fiat resistentia ("A two-fold geometrical investigation of the line of briefest descent, to which is added a geometric investigation of the solid of revolution that produces the minimum resistance") in which he discussed the brachistochrone as well as another problem, treated by Newton in book II of the Principia, also relating to what is modernly called the "calculus of variations".
In his book, Fatio drew attention to his own original work on the calculus from 1687, while stressing Newton's absolute priority and questioning the claims of Leibniz and his followers.
I recognize that Newton was the first and by many years the most senior inventor of this calculus: whether Leibniz, the second inventor, borrowed anything from him, I prefer that the judgment be not mine, but theirs who have seen Newton's letters and his other manuscripts. Nor will the silence of the more modest Newton, or the active exertions of Leibniz in everywhere ascribing the invention of the calculus to himself, impose upon any person who examines these papers as I have done.— Fatio, Lineæ brevissimæ (1699), p. 18
This provoked angry responses from Johann Bernoulli and Leibniz in the Acta Eruditorum. Leibniz stressed that Newton himself had admitted in his Principia to Leibniz's independent discovery of the calculus. Fatio's reply to his critics was finally published, in abbreviated form, in 1701. Fatio also corresponded on the history of calculus and on his own theory of gravity with Jacob Bernoulli, who was by then estranged from his brother Johann. Fatio's writings on the history of the calculus are often cited as precursors to the bitter priority dispute that would erupt between Newton and Leibniz in the 1710s, after John Keill effectively accused Leibniz of plagiarism.
Contributions to watchmakingEdit
In the 1690s, Fatio discovered a method for piercing a small and well-rounded hole in a ruby, using a diamond drill. Such pierced rubies can serve as jewel bearings in mechanical watches, reducing the friction and corrosion of the watch's internal mechanism, and thereby improving both accuracy and working life. Fatio sought unsuccessfully to interest Parisian watchmakers in his invention. Back in London, Fatio partnered with the Huguenot brothers Peter and Jacob Debaufre (or "de Beaufré"), who kept a successful watchmaking shop in Church Street, Soho. In 1704, Facio and the Debaufres obtained a fourteen-year patent (no. 371) for the sole use in England of Facio's invention relating to rubies. They later attempted unsuccessfully to have the patent extended to "the sole applying [of] precious and more common stones in Clocks and Watches".
In March 1705, Fatio exhibited specimens of watches thus jewelled to the Royal Society. The correspondence of Isaac Newton shows that in 1717 Fatio agreed to make a watch for Richard Bentley in exchange for a payment of £15, and that in 1724 he sought permission from Newton to use Newton's name in advertising his jewelled watches. Fatio's method for piercing rubies remained a speciality of English watchmaking until it was adopted in the Continent in 1768 by Ferdinand Berthoud. Jewel bearings are still used today in luxury mechanical watches.
Later life and deathEdit
Fatio was in Switzerland in 1699, 1700, and 1701. In Duillier he was reconciled to his father and collaborated with his brother Jean-Christopher in surveying the mountains around Lac Léman. He also undertook a deep study of the prophetic books in the Bible. Back in London, Fatio worked as a mathematical tutor in Spitalfields. In 1706 he began to associate with the Camisards, a radical group of Huguenot exiles who had fled from France during the Wars of Religion in that country. The group with which Fatio became affiliated was known as the "French prophets" and preached impending destruction and judgment.
The British government suspected the millenarian French prophets of contriving a political scheme, and in 1707 Élie Marion, Jean Daudé, and Fatio were tried before the Queen's Bench on charges brought against them by the mainstream Huguenot churches in England. The three were convicted of sedition and sentenced to the pillory. On 2 December, Fatio stood on a scaffold at Charing Cross with an inscription on his hat that read
Nicolas Fatio convicted for abetting and favouring Elias Marion, in the Wicked and counterfeit prophecies, and causing them to be printed and published, to terrify the Queen's people.
Fatio was among those who believed in the prophecy that Thomas Emes would be raised from the dead, attracting ridicule and condemnation even from his own brother. In 1711 Fatio travelled to Berlin, Halle, and Vienna as a missionary of the French prophets. A second mission in 1712–13 took him to Stockholm, Prussia, Halle, Constantinople, Smyrna, and Rome. Fatio then moved to Holland, where he composed written accounts of his missions and of the prophecies delivered during them. Some of these accounts, in French and Latin, were published in 1714.
Back in London, Fatio once again communicated with the Royal Society, of which his old friend Sir Isaac Newton had been president since 1704. In 1717 Fatio presented a series of papers on the precession of the equinoxes and climate change, subjects that he regarded from both a scientific and a millenarian perspective. In the spring of that same year he moved to Worcester, where he formed some congenial friendships and busied himself with scientific pursuits, alchemy, and study of the cabbala. Fatio would spend the rest of his life in Worcester and nearby Madresfield.
In 1732, through the influence of John Conduitt, Newton's nephew-in-law, Fatio endeavoured unsuccessfully to obtain a reward for having saved the Prince of Orange from Count Fenil's kidnapping plot. He also assisted Conduitt in designing Newton's funerary monument in Westminster Abbey and in writing the inscription for it. Fatio died, on 28 April or 12 May 1753, in Madresfield and was buried at the church of St. Nicholas, Worcester. His compatriot Georges-Louis Le Sage later purchased many of his scientific papers which, together with those of Le Sage, are now in the Geneva Library.
Throughout his long life Fatio proposed and developed various technological innovations. Undoubtedly the most significant of these was the jewel bearing, which is still used today in the manufacture of luxury mechanical watches. But Fatio's efforts as an inventor extended into many areas beyond watchmaking.
To optimise the capture of solar energy and thereby increase agricultural yields, Fatio suggested building sloping fruit walls, precisely angled to maximize the collection of heat from sunlight. Having supervised the building of such walls in Belvoir Castle, in 1699 he published an illustrated treatise that described his invention and included theoretical considerations about solar radiation. That work appeared with the imprimatur of the Royal Society. Fatio also proposed a tracking mechanism that could pivot to follow the Sun. Such ideas were superseded by the development of modern greenhouses.
One must add to the catalogue of Fatio's inventions his early work on improving the grinding of lenses for the objectives of telescopes, as well as his later proposals for taking advantage of a ship's motion to grind corn, saw, raise anchors, and hoist rigging. He also contrived a ship's observatory and measured the height of the mountains surrounding Geneva, planning, but never completing, a detailed map of Lac Léman.
Fatio regarded his proposed explanation of Newtonian gravity, in terms of collisions between ordinary matter and aetherial corpuscles as his greatest work. In this regard, Fatio might have been motivated in part by the success of his explanation of zodiacal light as sunlight scattered by an interplanetary cloud of fine particles. Despite some initial enthusiasm on the part of Newton and Halley, Fatio's mechanical theory of gravity soon fell into oblivion, chiefly because no drag by the aether on the motion of the planets could be detected in celestial motions. Fatio continued to revise and promote his theory until the end of his life, and a similar idea was re-discovered by Fatio's countryman Georges-Louis Le Sage. However, Fatio's account of his theory was not published until 1929, in an edition prepared by the German historian of mathematics Karl Bopp,, and then again independently in 1949 by Bernard Gagnebin, the conservator of manuscripts at the Geneva Library.
The Fatio-Le Sage theory attracted intermittent interest from physicists in the 18th and 19th centuries. In 1878, James Clerk Maxwell characterized it as "the only theory of the cause of gravitation which has been so far developed as to be capable of being attacked and defended." Another leading physicist who took this theory seriously was Nobel laureate J. J. Thomson. Even though the modern scientific consensus is that the Fatio-Le Sage theory is inviable as an account of gravity, the process that he described does give rise to an attractive inverse-square force between particles immersed in a rare medium at a higher temperature. George Gamow proposed in 1949 that such a "mock gravity" could have played a role in galaxy formation after the Big Bang. A. M. Ignatov showed in 1996 that a similar process produces an attraction between dust grains in a dusty plasma. For further information, see Le Sage's theory of gravitation.
Papers and manuscriptsEdit
Fatio left a number of manuscripts, some of which passed into the hands of Dr. Johnstone of Kidderminster, while other were acquired by Prof. Le Sage of Geneva, who also possessed a large collection of his letters. A few of his papers and letters are in the British Museum. Among them is a Latin poem entitled "N. Facii Duellerii Auriacus Throno-servatus" (Addit. MS. 4163), containing a curious narrative of Fenil's plot and a description of the jewelled watches. A series of letters to Sir Hans Sloane (ib. 4044) extend from 1714 to 1736. Other letters of his are in fasciculus 2 of C. Hugenii aliorumque seculi xvii. virorum celebrium Exercitationes Mathematicæ et Philosophicæ, 4to, the Hague, 1833. To vol. v. of Le Clerc's 'Bibliothèque Universelle,' 1687, Fatio contributed Réflexions sur une méthode de trouver les tangentes de certaines lignes courbes, qui vient d'être publiée dans un livre intitulé: Medicina Mentis. The Acta Lipsiensia for 1700 contains Excerpta ex suâ responsione ad excerpta ex litteris J. Bernouilly. Besides a paper in the Philosophical Transactions, xxviii. 172–6, entitled "Epistola ad fratrem Joh. Christoph. Facium, qua vindicat Solutionem suam Problematis de inveniendo solido rotundo seu tereti in quo minima fiat resistentia", Fatio contributed articles on astronomy and Hebrew metres in nearly every number of the Gentleman's Magazine for 1737 and 1738. In addition to the works already mentioned he was author of:
- "Epistola … de mari æneo Salomonis ad E. Bernardum" in the latter's De Mensuris et Ponderibus antiquis Libri tres, 8vo, Oxford, 1688.
- Fruit-walls improved by inclining them to the horizon, by a member of the Royal Society (signed N. F. D., i.e. N. Faccio de Duillier), 4to, London, 1699.
- N. Facii Duillerii Neutonus. Ecloga, 8vo (Ghent?), 1728.
- Navigation improved: being chiefly the method for finding the latitude at sea as well as by land, by taking any proper altitudes, with the time between the observations, fol., London, 1728).
With Jean Allut, Elie Marion, and other of the "French prophets", he issued a prophecy with the title Plan de la Justice de Dieu sur la terre dans ces derniers jours et du relévement de la chûte de l'homme par son péché ("Plan of God's Justice upon the earth in these last days, and of the release of man's fall by his sin") 2 parts, 8vo, 1714, of which a Latin version appeared during the same year.
Fatio appears as a supporting character in Michael White's novel Equinox (2006), Neal Stephenson's novel series, The Baroque Cycle (2003–04), and in Gregory Keyes's novel series, The Age of Unreason (1998–2001).
- Westfall, Richard S. (1980). Never at Rest: A Biography of Isaac Newton. Cambridge, UK: Cambridge University Press. p. 494. ISBN 978-0-521-27435-7.
- Iliffe, Rob (2012). "Servant of Two Masters: Fatio de Duillier between Christiaan Huygens and Isaac Newton". In Jorink, Eric; Maas, Ad. Newton and the Netherlands: How Isaac Newton was Fashioned in the Dutch Republic. Amsterdam: Leiden University Press. pp. 67–92. ISBN 978-90-8728-137-3.
- Mandelbrote, Scott (2005). "The Heterodox Career of Nicolas Fatio de Duillier". In Brooke, John; MacLean, Ian. Heterodoxy in Early Modern Science and Religion. Oxford and New York: Oxford University Press. pp. 263–296. ISBN 0-19-926897-5.
- Mandelbrote, Scott (2004). "Fatio, Nicolas, of Duillier (1664–1753)". Oxford Dictionary of National Biography (online ed.). Oxford University Press. doi:10.1093/ref:odnb/9056. (Subscription or UK public library membership required.)
- Registered in P. C. C. 64, Bettesworth
- Gagnebin, Bernard (1949). "Introduction". Notes and Records of the Royal Society. 6 (2): 105. doi:10.1098/rsnr.1949.0017.
- Fatio de Duillier, Nicolas (1949). "Texte: De la Cause de la Pesanteur". Notes and Records of the Royal Society. 6 (2): 125. doi:10.1098/rsnr.1949.0018.
- Zehe, H. (1980). Die Gravitationstheorie des Nicolas Fatio de Duillier. Hildesheim: Gerstenberg Verlag. ISBN 3-8067-0862-2.
- Kemble, John M., ed. (1857). "General Cavalier and the Religious War of the Cévennes". State Papers and Correspondence: Illustrative of the Social and Political State of Europe from the Revolution to the Accession of the House of Hanover. London: J. W. Parker. pp. 426–7.
- Quoted in Westfall, Richard S. (1980). Never at Rest: A Biography of Isaac Newton. Cambridge, UK: Cambridge University Press. pp. 713–14. ISBN 978-0-521-27435-7.
- Acta Eruditorum (May 1700), p. 203
- Hall, A. Rupert (1980). Philosophers at War: The Quarrel Between Newton and Leibniz. Cambridge, UK: Cambridge University Press. pp. 119–20. ISBN 0-521-52489-X.
- Nelthropp, Harry Leonard (1873). A Treatise on Watch-work: Past and Present. London: E. & F. N. Spon. pp. 237–241.
- "Notable Huguenot clockmakers and watchmakers". Howard Walwyn Fine Antique Clocks. 9 October 2015. Retrieved 29 April 2017.
- Boettcher, David (16 February 2016). "Jewels in watch movements". Vintage Watch Straps. Retrieved 29 April 2017.
- Gjertsen, Derek (1986). The Newton Handbook. London and New York: Routledge & Kegan Paul. pp. 198–200. ISBN 0 7102 0279 2.
- "Nicolas Fatio de Duillier (1664–1753)". Famous Watchmakers. Fondation de la Haute Horlogerie. Retrieved 29 April 2017.
- See his letter in William Seward, Anecdotes of Distinguished Persons, 4th edit. ii. 190–215.
- Gent. Mag. xxiii. 248
- Green, Worcester, ii. 93–4; cf. Nash, Worcestershire, vol. ii. supplement, p. 101
- Kidwell, Peggy (1983). "Nicholas Fatio de Duillier and Fruit-Walls Improved: Natural Philosophy, Solar Radiation, and Gardening in Late Seventeenth Century England". Agricultural History. 57 (4): 403–415. JSTOR 3742632.
- Butti, Ken; Perlin, John (1981). A Golden Thread (2500 Years of Solar Architecture and Technology). Van Nostrand Reinhold. pp. 42–46. ISBN 0-442-24005-8.
- Bopp, Karl (1929). "Die wiederaufgefundene Abhandlung von Fatio de Duillier: De la Cause de la Pesanteur". Drei Untersuchungen zur Geschichte der Mathematik. Schriften der Wissenschaftlichen Gesellschaft in Straßburg. De Gruyter. pp. 19–66.
- Rosenfeld, Léon (1969). "Newton's views on aether and gravitation". Archive for History of Exact Sciences. 6: 29. doi:10.1007/BF00327261.
- Maxwell, J. C. (1878), "Atom", in Baynes, T.S., Encyclopædia Britannica, 3 (9th ed.), New York: Charles Scribner's Sons, pp. 38–47
- Thomson, J. J. (1911), "Matter", in Chisholm, Hugh, Encyclopædia Britannica, 17 (11th ed.), Cambridge University Press, p. 895
- Gamow, George (1949). "On Relativistic Cosmogony". Reviews of Modern Physics. 21 (3): 367. Bibcode:1949RvMP...21..367G. doi:10.1103/RevModPhys.21.367.
- Ignatov, A.M. (1996). "Lesage gravity in dusty plasma". Plasma Physics Reports. 22 (7): 585–589. Bibcode:1996PlPhR..22..585I.
- Fatio de Duillier, N.: De la cause de la Pesanteur, 1690–1701, Bopp edition. On pp. 19–22 is an introduction by Bopp (in German). Fatio's paper starts at the end of p. 22 (in French).
- Fatio de Duillier, N.: De la Cause de la Pesanteur, 1690–1743, Gagnebin edition. For an introduction by Gagnebin, see Introduction
- Fatio de Duillier, N.: "Letters no. 2570, pp. 384–389 and 2582, pp. 407–412, 1690, Huygens Oeuvres, Vol. IX. These letters contain the first written expositions of his theory. Huygens gave an answer in letter no. 2572)
- MathPages – Nicolas Fatio and the Cause of Gravity