Part 6

I wish to thank Dr. Robert P. Multhauf, chairman of the Department of Science and Technology in the Smithsonian Institution's Museum of History and Technology, for encouragement in the writing of this paper and for the provision of opportunity to consult the appropriate sources. To Dr. W. James King of the American Institute of Physics, I am grateful for many provocative discussions on this and related topics.

FOOTNOTES:

A. VOLTA, "On the Electricity Excited by the Mere Contact of Conducting Substances of Different Kinds," Philosophical Transactions of the Royal Society of London (1800), vol. 90, pp. 403-431.

Some little-known but delightful observations in the prehistory of electromagnetism are described in a letter written by G. W. SCHILLING from London to the Berlin Academy on July 8, 1769, published as "Sur les phenomenes de l'Anguleil Tremblante" [Nouveaux Memoires de l'Academie Royale des Sciences et Belles-Lettres, 1770 (Berlin, 1772), pp. 68-74], translated to French from the original German. The letter recounts a multitude of experiments with various electric eels. The two observations of electromagnetic interest are that a piece of iron held by the hand in the eel's tank could be felt quivering even when the fish was stationary several inches away, and a compass needle showed a deflection, both in the water near the fish, and outside the tank, also with the fish stationary.

ABRAHAM BENNET, Philosophical Transactions of the Royal Society of London (1787), p. 26.

Op. cit. (footnote 1), p. 403.

Philosophical Magazine (1800), vol. 7, pp. 289-311. [For a facsimile reprint, see Galvani-Volta (Bern Dibner's Burndy Library Publication No. 7), Norwalk, Connecticut, 1952.]

MICHAEL FARADAY, Experimental Researches in Electricity, vol. 1 (London, 1839), paragraph 739, dated January 1834.

Ibid., sec. 741.

JAMES CUMMING, "On the Application of Magnetism as a Measure of Electricity," Transactions of the Cambridge Philosophical Society (1821), vol. 1, pp. 282-286. [Also published in Philosophical Magazine (1822), vol. 60, pp. 253-257.]

H. C. OERSTED, Experimenta Circa Effectum Conflictus Electrici in Acum Magneticam (Copenhagen, July 21, 1820).

Full details of Oersted's work and publications are in Oersted and the Discovery of Electromagnetism (Bern Dibner's Burndy Library Publication No. 18), Norwalk, Connecticut, 1961. The original Latin version and first English translation are reproduced in Isis (1928), vol. 34, pp. 435-444.

A. M. AMPERE, Annales de Chimie et de Physique (1820), vol. 15, p. 67. The word "galvanometer" had been used much earlier by BISCHOF, "On Galvanism and its Medical Applications," The Medical and Physical Journal (1802), vol 7, p. 529, for a form of goldleaf electroscope shown here in figure 2, but this use of the word does not seem to have been adopted by others.

Op. cit. (footnote 6), paragraph 283, dated January 1833. A similar attitude was expressed in the same year by CHRISTIE, Philosophical Transactions of the Royal Society of London (1833), vol. 123, p. 96: "I adopt the word current as a convenient mode of expression, ... but I would not be considered as adopting any theoretical views on the subject...."

Some prominent examples of this brevity of treatment are in E. HOPPE, Geschichte der Elektrizitaet (Leipzig, 1884); O. MAHR, Geschichtliche Einzeldarstellungen aus der Elektrotechnik (Berlin, 1941); R. S. WHIPPLE, "The Evolution of the Galvonometer," Journal of Scientific Instruments (1934), vol. 7, pp. 37-43; WILLIAM STURGEON, Scientific Researches (Bury, 1850); A. W. HUMPHREYS, "The Development of the Conception and Measurement of Electric Current," Annals of Science (1937), vol. 2, pp. 164-178.

M. SPETER, "Klaerung der Multiplikator-Prioritaetsfrage Schweigger-Poggendorf," Zeitschrift fuer Instrumentenkunde (1937) vol. 57, pp. 29-32.

T. SEEBECK, "Ueber den Magnetismus der Galvanischen Kette," Abhandlungen der Koenigliche Akademie der Wissenschaften zu Berlin (1820-1821), pp. 289-346. The phrase "Schweigger's multiplier" is used on page 319. The many experiments described in this paper added little or nothing to contemporary appreciation of the multiplier as an instrument.

J. S. C. SCHWEIGGER, Journal fuer Chemie und Physik (1821), vol. 31, pp. 1-18, 35-42. Pages 1-6 are the paper presented in Halle on September 16, 1820; pages 7-18 are the paper presented in Halle on November 4, 1820, and pages 35-42 are "a few additional words." The preface to the whole volume is dated January 1, 1821. A somewhat earlier public announcement referring to Schweigger's discovery appeared in the Allgemeine Literatur-Zeitung (November 1820), no. 296, cols. 622-624, but this was lacking in detail and seems not to have been noticed by any scientists.

P. ERMAN, Umrisse zu den physischen Verhaeltnissen des von Herrn Prof. Oersted entdeckten elektro-chemischen Magnetismus (Berlin, 1821). Hoppe (footnote 13) states that Erman's book was published in May; however, it is referred to in a letter dated April 3, 1821, by RASCHIG, Annalen der Physik (1821), vol. 67, pp. 427-436.

Op. cit. (footnote 16), vol. 32, pp. 38-50.

Annalen der Physik (1821), vol. 67, pp. 382-426, and footnote on pages 429-430 of same volume. The footnote accompanies the article by Raschig mentioned in footnote 17.

H. C. OERSTED, "Sur le Multiplier electro-magnetique de M. Schweigger, et sur quelques applications qu'on en a faites," Annales de Chimie et de Physique (1823), vol. 22, pp. 358-365.

"Versuche mit dem electrisch-magnetischen Multiplicator," Annalen der Physik (1821), vol. 67, pp. 427-436.

Transactions of the Cambridge Philosophical Society (1821), vol. 1, pp. 269-278.

Op. cit. (footnote 8).

The German word Kette has been translated as "circuit" throughout. Although the equivalence of these words is clear, for example, in Ohm's work of 1826, the context in which Kette is sometimes used in 1820 and 1821 indicates that the concept of a "circuit," in the sense of the wiring external to the source of electricity, has not been established. The wiring is regarded more as something incidental, used to "close" the cell, the cell being considered essentially the whole of the apparatus. This view underlies the many attempts to correlate the Oersted phenomena with cell materials and design, and with the use of such terms as "chemical magnetism" by Erman and others.

The reference here is to the Oersted-type experiments described in two papers by authors other than Schweigger on pages 19 to 34 of the volume.

Op. cit. (footnote 19), pp. 422-426.