Opusculum perpetua memoria dignissimum, De natura magnetis, et eius effectibus …

Cologne: Johann Birkmann, 1562.

First edition of this exceptionally rare, interesting, and notorious work – the second printed work on magnetism, preceded only by the Epistola de magnete of Peregrinus (1558) (which is virtually unobtainable). Taisnier’s work, in fact, contains a plagiarism of Peregrinus, which it reprints verbatim, and of the equally rare Demonstratio proportionum motuum localium (1554) of Benedetti (1530-90), which anticipates Galileo’s theory of falling bodies. But Taisnier’s book also contains important original contributions, notably to navigation. It “had a section on the relation of hull shape to speed in ship design. Its most valuable contribution was a long dissertation upon the causes and sequence of tides … [it] marked a definite step forward in tidal theory” (Waters, pp. 150-151). “The Epistola ranks as one of the most impressive scientific treatises of the Middle Ages. Not only did Peregrinus bring together virtually all the relevant, contemporary knowledge on magnetism, he added to it and, of the greatest importance, organized the whole into a science of magnetism. He formulated rules for the determination of magnetic polarity, which then enabled him to enunciate rules for attraction and repulsion, all of which would today form the basis of an introductory lesson on magnetism. As the two magnetic compasses and perpetual motion devices for clock and wheel testify, Peregrinus was also seriously concerned with the practical application of magnetic force. The subsequent influence of his treatise was considerable. The existence of at least thirty-one manuscript versions of it bears witness to its popularity during the Middle Ages. Of greater significance, however, was its eventual impact on Gilbert, who, in his famous De Magnete (1600), built upon the solid empirical rules on magnetic polarity and induction formulated by Peregrinus more than three centuries earlier” (DSB). Benedetti’s Demonstratio “sets forth his ‘buoyancy theory of fall’ [which] is in many respects identical with that which Galileo set forth in his first treatise De motu, composed at Pisa about 1590 but not published during his lifetime” (DSB). Taisnier’s work enjoyed greater circulation than either of the works on which it is based, and thus assisted greatly in the diffusion of their ideas. Johannes Kepler used Taisnier’s book when developing his theory of a magnetic force emanating from the Sun which drives the planets in their orbits (see DSB VIII, 295), and it was through Taisnier’s book that Benedetti’s ideas were transmitted to the Collegio Romano (Encyclopedia of the Scientific Revolution, p. 128). The only other complete copy of this book that we know of having appeared on the market is the Horblit copy, also in a modern binding, which was offered by H. P. Kraus in their Cat. 171 (ca. 1975) for $3200. The five copies, other than the present one, listed on ABPC/RBH, all lack the portrait leaf at the end (the Andrade copy, in modern vellum and lacking the portrait leaf, sold for $1400 in 1965). Only the Honeyman copy of Peregrinus has sold at auction in the last 80 years (£11,000 in 1980), and only the Macclesfield copy of Benedetti (part of a sammelband).

Provenance: ‘Est Zacharia Caimi’ (early title inscription); John Crerar Library, Chicago (bookplate and binding). We have not been able to identify the early owner, but he seems to have owned a significant library: the same inscription can be found in a copy of Della Porta’s De Humana Physiognomonia (1586) currently being offered in the trade, and in a copy of Swineshead’s Calculationes (1520) held by the Thomas Fisher Library at Toronto.

The contribution of this work to the causes and sequence of tides “was important, for it was the first detailed attempt to explain the causes of tides and their cyclical nature, and it is particularly interesting as it correctly associates tides with the sun as well as the moon. ‘Firstly and lastly, is to be known that the Sunne and Moone, both together every natural day … are the causes of flowyng and reflowyng or increase and decrease of the water of the sea twyce …’, Taisnier wrote, explaining that the sun and moon in opposition as well as in conjunction caused strong flowing tides, that is, spring tides, and that when they were in quadrature neap tides occurred, when the Venetian pilots said ‘l’aqua è stance’ … [he] was certain that strong winds could also affect the velocity of tidal streams as well as the times of high- and low-water. As this was coupled with the observation that ‘the straytenesse or narrownesse of places’ also affected the tidal flow, Taisnier was getting very close to associating the surface currents of the ocean with the prevailing wind systems” (Waters, pp. 150-151).

“Of the early years of Peregrinus (fl. 13th century), nothing is known save that he studied probably at the University of Paris, and that he graduated with the highest scholastic honors. He owes his surname to the village of Maricourt, in Picardy, and the appellation Peregrinus, or Pilgrim, to his having visited the Holy Land as a member of one of the crusading expeditions of the time. In 1269 we find him in the engineering corps of the French army then besieging Lucera, in Southern Italy, which had revolted from the authority of its French master, Charles of Anjou. To Peregrinus was assigned the work of fortifying the camp and laying mines as well as of constructing engines for projecting stones and fireballs into the beleaguered city.

“It was in the midst of such warlike preoccupations that the idea seems to have occurred to him of devising a piece of mechanism to keep the astronomical sphere of Archimedes in uniform rotation for a definite time. In the course of his work over the new motor, Peregrinus was gradually led to consider the more fascinating problem of perpetual motion itself with the result that he showed, at least diagrammatically, and to his own evident satisfaction, how a wheel might be driven round forever by the power of magnetic attraction. Elated over his imaginary success, Peregrinus hastened to inform a friend of his at home; and that his friend might the more readily comprehend the mechanism of the motor and the functions of its parts, he proceeds to set forth in a methodical manner all the properties of the lodestone, most of which he himself had discovered … The letter was addressed from the trenches at Lucera, Southern Italy, in August, 1269, to Sigerus de Foucaucourt, his “amicorum intimus,” the dearest of friends …

“An analysis of the Epistola shows that

(1) Peregrinus was the first to assign a definite position to the poles of a lodestone, and to give directions for determining which is north and which south;

(2) He proved that unlike poles attract each other, and that similar ones repel;

(3) He established by experiment that every fragment of a lodestone, however small, is a complete magnet, thus anticipating one of our fundamental laboratory illustrations of the molecular theory;

(4) He recognized that a pole of a magnet may neutralize a weaker one of the same name, and even reverse its polarity;

(5) He was the first to pivot a magnetized needle and surround it with a graduated circle;

(6) He determined the position of an object by its magnetic bearing as done today in compass surveying; and

(7) He introduced into his perpetual motion machine the idea of a magnetic motor, a clever idea, indeed, for a thirteenth century engineer.

“This rapid summary will serve to show that the letter of Peregrinus is one of great interest in physics as well as in navigation and geodesy. For nearly three centuries, it lay unnoticed among the libraries of Europe, but it did not escape Gilbert, who makes frequent mention of it in his De Magnete (1600); nor the illustrious Jesuit writers, Cabasus [Cabeo], who refers to it in his Philosophia Magnetica (1629), and Kircher, who quotes from it in his De Arte Magnetica (1641); it was well known to Jean Taisnier, the Belgian plagiarist, who transferred a great part of it verbatim to the pages of his De Natura Magnetis (1562), without a word of acknowledgment. By this piece of fraud, Taisnier acquired considerable celebrity, a fact that goes to show the meritorious character of the work which he unscrupulously copied” (Introduction to the English translation).

“If Peregrinus’ attempt to apply magnetic force to perpetual motion was misconceived, his use of it in the improvement of the compass was surely not. He described two compasses, one wet and one dry. The first (pt. 2, chap. 1), a floating compass, represents a considerable improvement over those that had been in use … With this instrument, perhaps the first mariner’s compass with divisions, not only could the direction of a ship be determined, but also the azimuth of the sun, moon, and stars … The second compass (pt. 2, chap. 2), dry and pivoted, was deemed by Peregrinus an improvement over the floating compass … Peregrinus appears to have been the first to describe such a compass” (DSB).

“Benedetti’s first important contribution to the birth of modern physics was set forth in the letter of dedication to his Resolutio [omnium Euclidis problematum aliorum. ad hoc necessario inuentorum, 1553]. The letter was addressed to Gabriel de Guzman, a Spanish Dominican priest with whom he had conversed at Venice in 1552. It appears that Guzman had shown interest in Benedetti’s theory of the free fall of bodies, and had asked him to publish a demonstration in which the speeds of fall would be treated mathematically … His demonstration was based on the principle of Archimedes, which probably came to his attention through Tartaglia’s publication at Venice in 1551 of a vernacular translation of the first book of the Archimedean treatise on the behavior of bodies in water. Benedetti’s “buoyancy theory of fall” is in many respects identical with that which Galileo set forth in his first treatise De motu, composed at Pisa about 1590 but not published during his lifetime.

“Although no mention of Benedetti’s theory has been found in books or correspondence of the period, lively discussions appear to have taken place concerning it, some persons denying the conclusion and others asserting that it did not contradict Aristotle. In answer to those contentions, Benedetti promptly published a second book, the Demonstratio (1554), restating the argument and citing the particular texts of Aristotle that it contradicted … Two editions of Benedetti’s Demonstratio, which was by no means a mere republication of the Resolutio, appeared in rapid succession. The first edition maintained, as did the Resolutio, that unequal bodies of the same material would fall at equal speed through a given medium. The second edition stated that resistance of the medium is proportional to the surface rather than the volume of the falling body, implying that precise equality of speed for homogeneous bodies of the same material and different weight would be found only in a vacuum. This correction of the original statement was repeated in Benedetti’s later treatment of the question in Speculationum (1585).

“Benedetti’s original publication of his thesis in 1553 was designed to prevent its theft; perhaps he had in mind the fate of Tartaglia’s solution of the cubic equation a few years earlier. But even repeated publication failed to protect it, and indeed became the occasion of its theft. Jean Taisnier, who pirated the work of Petrus Peregrinus de Maricourt in his Opusculum … de natura magnetis (1562), included with it—as his own—Benedetti’s Demonstratio. Taisnier’s impudent plagiarism enjoyed wider circulation than Benedetti’s original, and was translated into English by Richard Eden about 1578. Simon Stevin cited the proposition as Taisnier’s when he published his own experimental verification of it in 1586. But since Taisnier had stolen the Demonstratio in its earlier form, he was criticized by Stevin for the very fault which Benedetti had long since corrected in the second Demonstratio of 1554. Taisnier’s appropriation of his book ultimately became known to Benedetti, who complained of it in the preface to his De gnomonum (1574). The relatively small circulation of Benedetti’s works is evidenced by the fact that it was not until 1741 that general attention was first called to the theft, by Pierre Bayle” (DSB).

Jean Taisnier (1508-62) was a mathematician, philosopher, musician, astrologer and author of several books, among which are, as well as the present work, Astrologiae (1559), De usu annuli sphaerici (1550) and Opus mathematicum (1562). He travelled throughout Europe and a great part of Africa, Asia and America, collecting, he says, the views of the most expert men wherever he went. He taught at the universities of Rome, Ferrara, Venice, Padua, Florence and Palermo. Between 1530 and 1550 he was a member of the court of Emperor Charles V. He retired to Germany after the Emperor’s death, where he became choirmaster to the archbishop of Cologne, to whom the present work is dedicated.

Taisnier’s book was translated into English by Richard Eden (ca. 1521-76) under the title A very necessarie and profitable booke concerning navigation (London: Richard Jugge, ca. 1575). This extremely rare book (three copies on COPAC) is the first book in English on magnetism. The quotation in Waters is from Eden’s translation.

Wheeler Gift 53. The letter of Petrus Peregrinus on the magnet, A.D. 1269 (New York, 1904). Waters, The Art of Navigation in England in Elizabethan and Early Stuart Times, 1958.



Small 4to (187 x 138 mm), pp. [iv], 84, [1]. Device on title, woodcut portrait of the author on title verso and on recto of final leaf, illustrations, diagrams and initials in woodcut (title with two faint water-stains, browning and marginal light water-staining throughout, ink from title inscription showing through to portrait on verso, short tear in outer margin of K2). Modern blue panelled calf gilt, gilt library stamps on front cover.

Item #4307

Price: $15,000.00