The Natural Philosophy of William Gilbert and His Predecessors

Part 1

Produced by Chris Curnow, Joseph Cooper and the Online Distributed Proofreading Team at https://www.pgdp.net

CONTRIBUTIONS FROM

THE MUSEUM OF HISTORY AND TECHNOLOGY:

PAPER 8

THE NATURAL PHILOSOPHY OF WILLIAM GILBERT AND HIS PREDECESSORS

W. James King

By W. James King

THE NATURAL PHILOSOPHY OF WILLIAM GILBERT AND HIS PREDECESSORS

Until several decades ago, the physical sciences were considered to have had their origins in the 17th century--mechanics beginning with men like Galileo Galilei and magnetism with men like the Elizabethan physician and scientist William Gilbert.

Historians of science, however, have traced many of the 17th century's concepts of mechanics back into the Middle Ages. Here, Gilbert's explanation of the loadstone and its powers is compared with explanations to be found in the Middle Ages and earlier.

From this comparison it appears that Gilbert can best be understood by considering him not so much a herald of the new science as a modifier of the old.

THE AUTHOR: W. James King is curator of electricity, Museum of History and Technology, in the Smithsonian Institution's United States National Museum.

The year 1600 saw the publication by an English physician, William Gilbert, of a book on the loadstone. Entitled De magnete, it has traditionally been credited with laying a foundation for the modern science of electricity and magnetism. The following essay is an attempt to examine the basis for such a tradition by determining what Gilbert's original contributions to these sciences were, and to make explicit the sense in which he may be considered as being dependent upon earlier work. In this manner a more accurate estimate of his position in the history of science may be made.

William Gilbert, De magnete, magneticisque corporibus et de magno magnete tellure; physiologia nova, plurimis & argumentis, & experimentis, demonstrata, London, 1600, 240 pp., with an introduction by Edward Wright. All references to Gilbert in this article, unless otherwise noted, are to the American translation by P. Fleury Mottelay, 368 pp., published in New York in 1893, and are designated by the letter M. However, the Latin text of the 1600 edition has been quoted wherever I have disagreed with the Mottelay translation.

A good source of information on Gilbert is Dr. Duane H. D. Roller's doctoral thesis, written under the direction of Dr. I. B. Cohen of Harvard University. Dr. Roller, at present Curator of the De Golyer Collection at the University of Oklahoma, informed me that an expanded version of his dissertation will shortly appear in book form. Unfortunately his researches were not known to me until after this article was completed.

One criterion as to the book's significance in the history of science can be applied almost immediately. A number of historians have pointed to the introduction of numbers and geometry as marking a watershed between the modern and the medieval understanding of nature. Thus A. Koyré considers the Archimedeanization of space as one of the necessary features of the development of modern astronomy and physics. A. N. Whitehead and E. Cassirer have turned to measurement and the quantification of force as marking this transition. However, the obvious absence of such techniques in De magnete makes it difficult to consider Gilbert as a founder of modern electricity and magnetism in this sense.

Alexandre Koyré, Études galiléennes, Paris, 1939.

Alfred N. Whitehead, Science and the modern world, New York, 1925, ch. 3; Ernst Cassirer, Das Erkenntnisproblem, ed. 3, Berlin, 1922, vol. 1, pp. 314-318, 352-359.

However, see M: pp. 161, 162, 168, 335.

There is another sense in which it is possible to contend that Gilbert's treatise introduced modern studies in these fields. He has frequently been credited with the introduction of the inductive method based upon stubborn facts, in contrast to the methods and content of medieval Aristotelianism. No science can be based upon faulty observations and certainly much of De magnete was devoted to the destruction of the fantastic tales and occult sympathies of the Romans, the medieval writers, and the Renaissance. However, let us also remember that Gilbert added few novel empirical facts of a fundamental nature to previous observations on the loadstone. Gilbert's experimental work was in large part an expansion of Petrus Peregrinus' De magnete of 1269, and a development of works like Robert Norman's The new attractive, in which the author discussed how one could show experimentally the declination and inclination of a magnetized needle, and like William Borough's Discourse on the variation of the compass or magnetized needle, in which the author suggested the use of magnetic declination and inclination for navigational purposes but felt too little was known about it. That other sea-going nations had been considering using the properties of the magnetic compass to solve their problems of navigation in the same manner can be seen from Simon Stevin's De havenvinding.

For example, William Whewell, History of the inductive sciences, ed. 3, New York, 1858, vol. 2, pp. 192 and 217; Charles Singer, A short history of science to the nineteenth century, Oxford, 1943, pp. 188 and 343; and A. R. Hall, The scientific revolution, Boston, 1956, p. 185.

Petri Peregrini maricurtenis, de magnete, seu rota perpetui motus, libellus, a reprint of the 1558 Angsburg edition in J. G. G. Hellmann, Rara magnetica, Berlin, 1898, not paginated. A number of editions of Peregrinus, work, both ascribed to him and plagiarized from him, appeared in the 16th century (see Heinz Balmer, Beiträge zur Geschichte der Erkenntnis des Erdmagnetismus, Aarau, 1956, pp. 249-255).

Hellmann, ibid., Robert Norman, The newe attractive, containyng a short discourse of the magnes or lodestone, and amongest other his vertues, of a newe discovered secret and subtill propertie, concernyng the declinyng of the needle, touched therewith under the plaine of the horizon. Now first founde out by Robert Norman Hydrographer. London, 1581. The possibility is present that Norman's work was a direct stimulus to Gilbert, for Wright's introduction to De magnete stated that Gilbert started his study of magnetism the year following the publication of Norman's book.

Hellman, ibid., William Borough, A discourse of the variation of the compasse, or magneticall needle. Wherein is mathematically shewed, the manner of the observation, effects, and application thereof, made by W. B. And is to be annexed to the newe attractive of R. N. London, 1596.

Hellman, ibid., Simon Stevin, De havenvinding, Leyden, 1599. It is interesting to note that Wright translated Stevin's work into English.

Instead of new experimental information, Gilbert's major contribution to natural philosophy was that revealed in the title of his book--a new philosophy of nature, or physiology, as he called it, after the early Greeks. Gilbert's attempt to organize the mass of empirical information and speculation that came from scholars and artisans, from chart and instrument makers, made him "the father of the magnetic Philosophy."

As Edward Wright was to call him in his introduction.

Gilbert's De magnete was not the first attempt to determine the nature of the loadstone and to explain how it could influence other loadstones or iron. It is typical of Greek philosophy that one of the first references we have to the loadstone is not to its properties but to the problem of how to explain these properties. Aristotle preserved the solution of the first of the Ionian physiologists: "Thales too ... seems to suppose that the soul is in a sense the cause of movement, since he says that a stone has a soul because it causes movement to iron." Plato turned to a similar animistic explanation in his dialogue, Ion. Such an animistic solution pervaded many of the later explanations.

Part 2

Aristotle, On the soul, translated by W. S. Hett, Loeb Classical Library, London, 1935, 405a20 (see also 411a8: "Some think that the soul pervades the whole universe, whence perhaps came Thales' view that everything is full of gods").

Plato, Ion, translated by W. R. M. Lamb, Loeb Classical Library, London, 1925, 533 (see also 536).

That a mechanical explanation is also possible was shown by Plato in his Timaeus. He argued that since a vacuum does not exist, there must be a plenum throughout all space. Motion of this plenum can carry objects along with it, and one could in this manner explain attractions like that due to amber and the loadstone.

Plato, Timaeus, translated by R. G. Bury, Loeb Classical Library, London, 1929, 80. It is difficult to determine which explanation Plato preferred, for in both cases the speaker may be only a foil for Plato's opinion rather than an expression of these opinions.

Another mechanical explanation was based upon a postulated tendency of atoms to move into a vacuum rather than upon the latter's non-existence. Lucretius restated this Epicurean explanation in his De rerum natura. Atoms from the loadstone push away the air and tend to cause a vacuum to form outside the loadstone. The structure of iron is such that it, unlike other materials, can be pushed into this empty space by the thronging atoms of air beyond it.

Lucretius, De rerum natura, translated by W. H. D. Rouse, Loeb Classical Library, London, 1924, bk. VI, lines 998-1041.

Continue reading The Natural Philosophy of William Gilbert and His Predecessors free in the Wunder reader →