In the years following the publication of De Magnete in 1600 and the death of William Gilbert in 1603 a dispute developed between two leading English magnetists, William Barlow (1544 – 1625) and Dr Mark Ridley (1560–c. 1624), as to which of them was Gilbert’s true disciple.
We have already met William Barlow, son of a bishop, who was a successful career Church of England cleric, who never went to sea but became an expert on magnetism and navigation and was especially known for his mariner’s compass and variation compass designs. In 1605, he was appointed tutor and chaplain to Henry Frederick, Prince of Wales (1594–1612). Later, 1608 or 1609, the mathematician Edward Wright (1561–1615) was also appointed a tutor of Henry Frederick. Both Barlow and Wright were closely involved in the genesis of William Gilbert’s De Magnete. Barlow had also published a demonstration of Wright’s Mercator projection “obtained of a friend of mone of like professioin unto myself,” in his The Navigator’s Supply (1597). Both men lost their positions as tutor, when Henry Frederick died.
We now leave Barlow for the moment and turn our attention the Mark Ridley, who we first met as one of the residents of Gilbert’s Wingfield house in London. In many ways Ridley’s career paralleled that of his erstwhile landlord. Ridley was born the second son of the six children of the Lancelot Ridley rector of Stretham in Cambridgeshire. Lancelot Ridley was an early prominent Protestant, promoted under Thomas Cranmer and favoured during the reign of Edward VI. He was subsequently deprived under Mary but rose again to prominence under Elizabeth I. Mark matriculated as a pensioner at Claire College Cambridge in 1577, graduating BA in 1581 and MA in 1584. He was licenced to practice medicine by the College of Physicians in 1590 and graduated MD in 1592.
On 27 May 1594 he was appointed by Elizabeth, on the recommendation of William Cecil, to serve Feodor Ivanovich, the tsar of Russia as physician.
He worked for five years in Moscow and on the death of Tsar Feodor in 1599, he was appointed physician to of his successor, Boris Godunov. Elizabeth requested that he be allowed to return to London in that year and Boris Godunov wrote to her commending him for his faithful service and releasing him.
Ridley became an active member of the College of Physicians and like Gilbert before him rose in their ranks, being elected censor in 1607. Over the years he was regularly elected to various offices in the organisation. Interestingly, Ridley is perhaps more significant as the author of the two Russian-English dictionaries than for his writings on magnetism.
While living in Russia between 1594 and 1599, he compiled two manuscript dictionaries of Russian: a Russian-English dictionary of 7,203 entries entitled A dictionarie of the vulgar Russe tongue and an English-Russian dictionary of 8,113 entries entitled A dictionarie of the Englishe before the vulger Russe tonnge. The former includes a short grammar of Russian on the first eight folios. Both dictionaries are now held at theBodleian Library at the University of Oxford (MSS Laud misc. 47a and 47b). (Wikipedia)
Gilbert’s De Magnete was, of course, not without its critics. But in the early phase things remained fairly quiet, especially in England, where the book and its author were much admired. However, between 1603 and 1604 the splendidly named and titled Guillaume de Nautonier, sieur de Castel-Franc au haut Languedoc, Géographe du roi Henri IV (1560– 1620)
published the equally splendidly titled:
Mecometrie de leymant cest a dire La maniere de mesurer les longitudes par le moyen de l’eymant. Par laquelle est enseigné, un tres certain moyen, au paravant inconnu, de trouver les longitudes geographiques de tous lieux,–aussi facilement comme la latitude. Davantage, y est monstree la declinaison de la guideymant, pour tous lieux. Œuvre nécessaire aux admiraux, cosmographes, astrologues, geographes, pilotes, geometriens, ingenieux, mestres des mines, architectes, et quadraniers. (The mecometry of the loadstone or the way to determining the longitude by means of the loadstone…)
In this work Le Nautonier accepts Gilbert’s claim that the Earth is a magnet but claims that he discovered this independently, although, unlike Gilbert, he offers no experiments or other proofs to back up his claim. He was the first to state that the Earth is a tilted dipole, giving 67°N and 67°S for their latitudes and by modern reckoning approximately 30°E and 150°W as their longitudes. He stated that the Earth was a perfect sphere, and, as the book title states, resurrected the already debunked theory that magnetic variation was regular and using it one could determine longitude. He devoted a lot of space to refuting Gilbert’s explanations of the irregularities in variation. Initially there was no reaction to this book in England, although it would be thoroughly debunked in France by Didier Dounot (1574–1640), professor for mathematics on the Académies du roi, in his Confutation de l’invention des longitudes ou De la mecometrie de l’eymant. Cy devant mise en lumiere souz le nom de Guillaume le Nautonnier, sieur de Castel-Franc au haut Languedoc (1611)
The first reactions in England were triggered in 1608 by the publication by Anthony Linton, chaplain to Charles, Lord Howard of Effingham, who served as High Admiral from 1585–1618, of his Newes of the Complement of the Art of Navigation. And of the Mightie Empire of Cataia Together with the Straits of Anian.
In this rather strange volume, Linton, “after citing the criticisms of the art of navigation of Humphrey Gilbert, Thomas Digges, William Borough, Richard Polter, and Edward Wright, whose chart he praised, he pointed out that in navigation position-finding was still imperfect.”[1] Rather stating the obvious. He then claimed that any navigator could ‘make his conclusions of Latitude, Longitude, and Variation,’ as accurately ‘as is possible to be done in any other Mathematicall practice in use amongst us’ by ‘continued observation’, and by exploiting the existence of the two magnetic poles. By the use of certain globes and charts of his devising, obtainable at a price, and ‘in six other ways’, the navigator, knowing , ‘the vaiation of the Compasse and the Latitude of the place’ would find out by Aritmeticall calculation the true longitude of the same place’. However, for the satisfactory working of this admirable but obscurely worded system there appeared to be one serious drawback only, namely, that it required ‘professors of greater skill and practice in the Mathematics, then now commonly found’.[2] This very jumbled account obviously preaches the same gospel as Le Nautonier’s early work and raises the question, whether Linton had plagiarised it, to which we don’t know the answer.
Both of Henry Frederick’s navigation tutors now responded to Linton and Le Nautonier’s arguments. De Magnete was written in Latin and first got translated into English in the nineteenth century. This meant that his theories were not accessible to the mariners who couldn’t read Latin. Barlow wrote a manuscript presenting and explaining Gilbert’s ideas on magnetism and the compass in English. In this work he argued against and debunked the theory propagated by Linton and Le Nautonier. Barlow gave a copy of the manuscript to Sir Thomas Chaloner (1559–1615), a courtier and Governor of the Courtly College for the household of Prince Henry Frederick, so basically Barlow’s employer as chaplain and tutor to the prince. Chaloner manage to lose this manuscript as well as a second copy that he had agreed to have published. This was the situation in 1615, when Chaloner died.
Edward Wright simply refuted the argument in an appendix to the expanded second edition of his Certaine Errors in Navigation, arising either of the Ordinarie Erroneous Making or Vsing of the Sea Chart, Compasse, Crosse Staffe, and Tables of Declination of the Sunne, and Fixed Starres Detected and Corrected published in 1610, in which he listed the observed variation in many places. The volume was dedicated to “THE HIGH AND MIGHTIE PRINCE HENRY; eldest Son to our soueraigne Lord King Iames: Prince of Wales, Duke of Cornwell, Earle of Chester, &c.”
Ridley entered the fray in 1613 with the publication of his first book on magnetism:
A SHORT TREATISE of Magneticall Bodies and Motions. By Marke Ridley Dr in phisicke and Philosophie Latly Physition to the Emperour of Russia, and one of ye eight principals or Elects of the Colledge of Physitions in London. London Printed by Nicholas Okes. 1613.
Like Barlow he presented his theories in English for those who couldn’t read Latin. He debunked the various myths about the healing power of magnets etc and propagated the theories of Gilbert as presented in De Magnete. He then goes on to debunk the theories of Linton and Le Nautonier. After which he presents his own incorrect theory:
‘when travelling or sailing … it will be very necessary for thee to be stored with the Marriners Compasse for the sea … to know the way … and also to have the Inclinatory-needle truly placed in his ring, and the Directory needle, or a little flie Magneticall in the boxe, fastened at the bottome … for to know under what latitude thou art every day of thy voyage …’ Now one of the chief purposes of his book was to describe the benefits that would arise from the use of ‘the Directory-Magneticall-needle … for the description of Ports, Havens, Forelands, Capes, Bayes, and Rivers, for the more perfect making of Sea-cardes … and all Mathematicall instruments for measuring and surveying …’ and to explain the manner of using it. Yet the instrument was fundamentally unsound, for the mutual attraction and repulsion of the magnetical needles in close juxtaposition, such as he envisaged, foredoomed it to failure because of the resultant errors.[3]
Ridley then goes on to deliver a wide ranging account of loadstones and compasses followed by the latest discoveries of Galileo and Kepler. He gives accounts of Gilberts theory of variation, Blagrave’s Mathematicall Jewell, preferring Blagrave’s astrolabe to that of Gemma Frisius, accounts of the work of Wright, Brigg’s tables in Blunderville’s book, The Seven Planets, a description of a quadrant and the log-line etc, etc.
The publication of Ridley’s Magneticall Bodies possibly inspired a fifth editions of Robert Norman’s The Newe Attractive and William Borough’s A Discourse on the Variation of the Cumpas in 1614 and it almost certainly prompted Barlow to publish his manuscript from 1609 in 1616 as:
MAGNETICALL Aduertisements : or DIVERS PERTINENT obserruations, and approued experiments concerning the nature and properties of the Load-stone: Very pleasant for knowledge, and most needful for practice, or trauelling, or framing of Instruments fir for trauellers both by Sea and Land.
Act. 17.26 He hath made of one bloud all nations of men for to dwell on the face of the earth, and hath determined the times before appointed, and the bounds of theior habitation, that they should seeke the Lord, &c.
LONDON; Printed by Edward Griffin for Timothy Barlow, and are to be sold at his shop in Pauls Church-yard at the signe of the Bull-head. 1616.
He didn’t name Ridley directly but referred to his “propositions set abroad in another man’s name and yet some of them not rightly understood by the partie usurping them.”[4] He wrote:
I was the first that made the inclinatory instrument transparent to be used pendant, with a glass on both sides, and a ring at the top … and moreover I hanged him in a compass box, wjere with two onces weight he will be fit for use at sea. I first found out and showed the difference between iron and steel, and their tempers for magnetical uses … I was also the first that showed the right way of touching needles …[5]
To demonstrate that he, not Ridley, was Gilbert’s heir he stated that he had been researching magnetism since 1576 and that Gilbert had appreciated his contributions. To prove this, he included a letter that Gilbert had sent to him in 1602. This is in fact the only letter of Gilbert’s that has survived:
To the Worshipfull my good friend, Mr. William Barlowe at Easton by Winchester.
Recommendations with many thanks for your paines and courtesies, for your diligence and enquiring, and finding diuers good secrets, I pray proceede with double capping your load-stone you speake of, I shall bee glad to see you, as you write, as any man, I will haue any leisure, if it were a moneth, to conferre with you, you have shewed mee more–and brought more light than any man hath done. Sir, I will commend you to my L. of Effingham, there is heere a wise learned man, a Secretary of Venice, he came sent by that State, and was honourably received by her Majesty, he brought me a lattin letter from a Gentle-man of Venice that is very well learned, whose name is Iohannes Franciscus Sagredus, he is a great Magneticall man, and writeth that hee hath conferred with diuers learned men in Venice and with Readers of Padua, and reporteth wonderfull liking of my booke, you shall have a copy of the letter: Sir, I propose to adioyne an appendix of six or eight sheets of paper to my booke after a while, I am in hand with it of some new inuentions and I would haue some of your experiments, in your name and inuention put into it, if you please, that you may be knowen for an augmener of that art. So for this time in haste I take my leaue the xiiyth of February.
Your very louing friend,
W. Gilbert[6]
One major bone of contention between the two disciples of Gilbert was his embrace of Copernicanism with his assumption of a magnetic diurnal rotation of the Earth. As a conservative official of the Church, Barlow totally rejected this aspect of Gilbert’s work, remaining a staunch geocentrist. Ridley, however, going further than Gilbert, adopted a full heliocentric cosmology, as can be seen from his inclusion of the newest results from Galileo and Kepler in his book.
Barlow’s veiled accusation of plagiarism did not escape Ridley and he responded with a pamphlet: Magneticall Animadversions. Made by Dr Mark Ridley, Doctor in Physicke. Upon certain Magneticall Advertisements, lately published, From Maister William Barlow. (1617) His criticism was scathing:
‘There is almost no proposition in this book which most Mariners, Instrument-Makers, Compasse -makers, Cocke-makers, and Cutlers of the better and more understanding sort around London and the Suburbs have not known, practized, and made long before.’ His so-called inventions were ‘most of them in the Doctor Gilbert’s Booke, as I said before, or else such ordinary things that any ingenious workman hath or may easily invent or make; unles you hold all men Dulberts like your rare workman of Winchester.’[7]
Barlow’s response came immediately in his, A Briefe Discovery of the Idle Animadversions of Marke Ridley (1618):
This time it was personal. He tried to discredit Ridley, suggesting that he had morally compromised himself in order to ‘in so short a time become [the Russian] Empoerors principall Physition.’ In a double entendre to Ridley’s observations or ‘looks’ with the new-fangled telescope, he insinuated that the youthful Ridley had seduced the Czar, ‘for his lookes … are his meanes.’[8]
Ridley delivered a parting shot with his, Appendix or an Addition … unto his Magneticall Treatise in answer to M. Barlow (1618).
Despite Ridley’s attacks, Barlow reprinted his Magneticall Advertisements unchanged, except for a new title page, in 1618.
And so, the verbal war between the two heirs of William Gilbert ground to a halt. In their major publications, in this unpleasant exchange, both had made important contributions to the ongoing debate on magnetism and the compass, most importantly making much of Gilbert’s work accessible in English, for those unable to read Latin. However, at the same time they had made a public spectacle of themselves in their bitter dispute, a behaviour that was, unfortunately all too common amongst scholars during the Renaissance.
[1] David W. Waters, The Art of Navigation in England in Elizabethan and Early Stuart Times, Yale University Press, New Haven, 1958, p. 274.
[2] Waters pp.274-5.
[3] Waters p. 334
[4] Stephen Pumfrey, Latitude & The Magnetic Earth, Icon Books, Cambridge2003 p. 207
[5] Waters p. 337
[6] William Gilbert, De Magnete, trans. P. Fleury Motteley, Dover Books, NY, 1958, p. xxvi
[7] Pumfrey, p. 209
[8] Pumfrey, p. 209
The Renaissance Mathematicus 
So when did that stop? Still going strong with Newton…
Certainly scientific disagreements haven’t disappeared. In the formal journals, perhaps a level of civility prevails (or is enforced by the editors), but on blogs, it’s still a free-for-all.
Not to mention on
TwitterX.