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Armed Lodestone, European, mid-18th century

Armed Lodestone, European, mid-18th century
Lodestone, iron, brass, 12 (with handle) x 7 x 4½ in. Gift of Charles William Dabney, 1817.

This mysterious article is called, in the history of science, an “armed lodestone,” an object of wonderment in seventeenth- and eighteenth-century Europe. Lodestone, which is a rare form of the mineral magnetite, is naturally and permanently magnetic; exposure to lightning is considered one cause of its magnetism. (Magnetite itself is not necessarily magnetic.) By “arming” a lodestone with two iron caps attached to its two magnetic poles, the magnetic power of the lodestone is strengthened. Lodestones thus armed were often encased in a metal armature, as is the Boston Athenæum’s example, which is in an elaborately repousséed brass case (plate XX). This remarkable object was presented to the Athenæum in 1817 by Charles William Dabney of Fayal, an island in the Azores where he was soon to become the U. S. consul.[1] The stylistic features of the armature suggest that it is of eighteenth-century, continental manufacture.

The lodestone—a naturally occurring permanent magnet—was, to many ancient cultures, an awe-inspiring curiosity.[2] That a lodestone could attract iron without contact left St. Augustine “thunderstruck,” and in the fourth century the Chinese knew that “the magnet draws iron and the amber attracts mustard seeds.”[3] In many cultures a powerful lodestone commanded a high price, and some ancient thinkers imagined that the lodestone had a soul. Throughout Europe’s Middle Ages, the lodestone’s wondrous attraction to iron was observed but not understood: diamonds and garlic were once thought to annul the power of the lodestone, for example, and the lodestone was supposed to cure men of an array of ailments, from distemper to gout. The lodestone was also sometimes considered a machination of the Devil.[4] Its only practical use was as a magnetic compass or as a tool with which to re-magnetize one.

As the age of empirical science dawned, the lodestone was subjected to experiments, most notably in De magnete by William Gilbert, published in 1600. Gilbert explained how to “arm” a lodestone and observed that “a lodestone with such an appliance, which only bore four ounces of iron, will now raise twelve.”[5] Galileo admired Gilbert’s book and soon procured a magnificent lodestone for the young Cosimo de’ Medici II. Galileo also made several armed lodestones of his own.[6] Gilbert’s armed lodestones were ovoid or spherical as were some of Galileo’s, but Galileo also made some in rectangular shapes, closer in form to the Athenæum’s example.[7]The original function of the armed lodestone was to demonstrate that arming one would greatly increase its lifting power. (An armed lodestone is supposed to have a “keeper,” a horizontal iron bar that attaches to the projecting feet of two iron poles and supports a weight hung from it. The Athenæum’s example is missing its keeper.) In the century that followed, lodestones figured prominently in the European imagination. In 1681 over thirty were recorded among the possessions of the Royal Society, and in Gulliver’s Travels (1723) Jonathan Swift discussed “a lodestone of a prodigious size, in shape resembling a weaver's shuttle," that levitated the floating island of Laputa.[8]

Armed Lodestone with lid removed.

Even as the study of it gave rise to the understanding of the earth as a giant magnet, the lodestone still remained half in the realm of magic, prized sometimes for its supposed talismanic or healing properties. Examples of armed lodestones come in various shapes and sizes, and even include gold rings that encase a small lodestone with iron poles.[9] Both Queen Anne and King George III had armed lodestones in their collections. By the end of the eighteenth century, however, the use of the armed lodestone had declined rapidly after the manufacture of artificial steel magnets became possible. Today armed lodestones are rare; most are in museums of science rather than museums of art.

Already past the heyday of its genre, this armed lodestone arrived at the Athenæum in 1817. In its early years, the Athenæum, following its European predecessors, acquired a surprisingly large amount of scientific apparatus as well as natural history specimens. A prospectus circulated at the time of the Library’s founding in 1807 expressed a clear hope to establish at the Athenæum a MUSEUM or CABINET, which shall contain specimens from the three kingdoms of nature, scientifically arranged; natural and artificial curiosities, antiques, coins, medals, vases, gems, and intaglios [and] a LABORATORY, and an APPARATUS for experiments in chemistry and natural philosophy, for astronomical observations, and geographical improvements.[10]

In 1812, for example, Obadiah Rich, one of the founders, deposited a cabinet of natural history in the fledgling institution, and two years later Harvard Professor John Gorham gave five cases of chemical apparatus.[11] Offers of scientific items were frequent. Shortly after the gift of this armed lodestone in 1817, a man arrived at the Athenæum to present to Shaw a “famous fish” caught recently by an “industrious mechanic” in a river in New Bedford (and subtly demanded a remuneration).[12] In the Pearl Street Athenæum, Room 13 housed the growing assortment of scientific objects and specimens, and Seth Bass, the new Librarian, described it in 1825 with dismay: “Minerals, Shells and other articles, not arranged nor catalogued (and may be called a Museum burlesque)!!"[13] The Athenæum’s collecting focus gradually became narrower, however, and already in 1829 the Trustees decided to decline “stuffed skins of animals” while still accepting deposits of “shells and minerals.”[14] The trend continued, and the shortage of space only encouraged such selectivity.

By the end of the nineteenth century most objects of the scientific category had left the Athenæum’s collection, but this armed lodestone remained in it, probably because of its decorative appearance. It was deposited in the Museum of Fine Arts in Boston in 1878 or 1879, where it stayed until its return to the Athenæum in the 1970s. Surely its identity has been a mystery at times. It is a relic of an early modern fascination with magnetism and a reminder of the Athenæum’s early role as a depository of so much that fostered “the science of the learned, the taste of the refined, and the improved and cultivated character of the citizens at large.”[15] It is an object that sits at the juncture of science and art, from an era before the two went separate ways.


Hina Hirayama from, Stanley Ellis Cushing and David B. Dearinger, eds., Acquired Tastes: 200 Years of Collecting for the Boston Athenæum (2006): 352-355. Copyright © The Boston Athenæum.

The author thanks Jane Wess, Senior Curator of Science, Science Museum, London, for assisting with research for this essay.

[1] A reference to the letter (unlocated) that accompanied the armed lodestone, from J. Grafton, August 18, 1817, is in the Art Department files. The lodestone is recorded as a gift on August 19, 1817 in the Athenæum’s Donation Book.
[2] For history of the lodestone, see Alfred Still, Soul of Lodestone: The Background of Magnetical Science (New York: Murray Hill Books, Inc., 1946); M. Blackman, “The Lodestone: A Survey of the History and the Physics,” Contemporary Physics 24 (1983): 319-331; Allan Mills, “’Armed’ Lodestones,” Bulletin of the Scientific Instrument Society 81 (2004): 26-30; and Allan A. Mills, “The Lodestone: History, Physics, and Formation,” Annals of Science 61 (2004): 273-319.
[3] Still, 20 and 22.
[4] Still, 37.
[5] Still, 144.
[6] Colin A. Ronan, Galileo (New York: G. P. Putnam’s Sons, 1974), 99-100.
[7] Some of Galileo’s armed lodestones are in the collection of the Institute and Museum of the History of Science, Florence.
[8] Mills, “The Lodestone: History, Physics, and Formation,” 286.
[9] Sizable collections of armed lodestones are at the Science Museum, London; National Maritime Museum, London; and the Museum of the History of Science, Oxford University.
[10] “Memoir of the Boston Athenæum, with the Act of Incorporation, and Organization of the Institution (1807),” in Quincy, 28.
[11] BA Trustees Records, January 6, 1812. The donor of the armed lodestone, Charles William Dabney, may have known Obadiah Rich, since the latter was the U. S. Consul to Spain in 1816-1820 and 1834-1835. Letter from Professor Gorham is in BA Letter Book, March 21, 1814.
[12] BA Letter Book, November 13, 1817.
[13] Seth Bass, “Schedule of the Books and other Property belonging to the Boston Athenæum,” in his “Report to the Trustees,” BA Letter Book, July 11, 1825.
[14] BA Trustees Records, May 12, 1829.
[15] Quincy, 31.