ally 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.

[1] 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. Koyre considers the Archimedeanization of space as one of the
necessary features of the development of modern astronomy and
physics.[2] A. N. Whitehead and E. Cassirer have turned to measurement
and the quantification of force as marking this transition.[3]
However, the obvious absence[4] of such techniques in _De magnete_
makes it difficult to consider Gilbert as a founder of modern
electricity and magnetism in this sense.

[2] Alexandre Koyre, _Etudes galileennes_, Paris, 1939.

[3] 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.

[4] However, see