Stones and dust hardly seem the things of romance. And yet the behaviour of these particular stones and this special "dust" is frequently used as a metaphor for the power of romantic attraction. However, that may not be immediately obvious to those of us living in the twenty-first century, because these are the names which would have been used in the Regency for naturally occuring elements. Today's romance authors tend to use the modern-day names for similar, but man-made, versions of these objects.
Of lodestones and smith's dust ...
were known as far back as ancient times. These stones were typically composed of the naturally occuring mineral magnetite
, which is the most strongly and permanently magnetic of the earth's minerals. By the Middle Ages, it was understood that the magnetic property of this mineral could be used for navigation at sea. And so it was called the "lodestone," literally, the "way-stone," the stone that showed the way. Previously mariners had depended on the lodestar
, the star which showed the way, in most cases, the pole star, Polaris
. However, it is the ancient Chinese who had the most romantic name for the lodestone. They called it tzhu shih
, meaning the "loving stone," perhaps because of its "attractive" properties.
Magnetite was typically found in veins running through iron ore deposits at shallow depths. It is believed that lighting strikes into these veins of mineral caused them to become magnetized. For that reason, the magnetic power of lodestones can vary widely. Lodestones contain iron molecules, so they are usually of a dark brown or black color. By the seventeenth century, it was discovered that the magnetism of a lodestone could be increased by attaching small blocks of iron at each pole.
Lodestones fall in the middle of the Mohs hardness scale
. Thus it was relatively easy to work the mineral into various shapes, most popularly into spheres, which were considered the most valuable. These spheres were known as terrellae
, or "little Earths," because, from the late seventeenth century, it was believed that lodestones in the shape of the Earth could reproduce the rotation of the planet. By the Regency, it was recognized that this was scientifically impossible, but these terrellae
remained collectible for wealthy gentlemen, and occasionally ladies, with an interest in science. Most of these terrellae
were usually set in elaborate mounts made of precious metals, often set with precious or semi-precious stones, to showcase the spheres great value.
Lodestones are always naturally occuring magnets, though they might be enhanced by the application of small iron blocks at each pole. By the seventeenth century, it was discovered that other metals could be magnetized to make artificial magnets. However, the process was extremely labor-intensive, as the only way to accomplish this was to rub the piece of metal to be magnetized with a lodestone until that metal acquired magnetic properties. This process could take hours or even days. Later it was discovered that metal could be magnetized with heat, which took less time, but required more skill. Softer metals would become magnetized by heat more quickly, but would also loose their magnetism more quickly, while harder metals took much longer to become magnetized, but they would also hold their magnetic property for much longer, usually permanently. However, if the metal was heated above a certain temperature, now known as the Curie point
, it would lose its magnetic property. In most cases, the magnetism would return to the metal as it cooled.
But should a Regency gentleman, or lady, have had a lodestone, how would they have demonstrated its magnetic properties? The same way any science teacher does today, they would have brought their lodestone close to a clump of iron filings
. However, in the Regency, these small iron particles were known as "smith's dust." This special dust was comprised of the chippings and dross from the anvil over which a blacksmith worked. At the end of each day, this dust was swept up and stored. Those in need of smith's dust would visit their local blacksmith to purchase this valuable commodity. But why would anyone want the sweepings from the floor of the blacksmith's shop?
The use of smith's dust as a companion to a lodestone was only a small part of the demand for this smithing by-product. Vast amounts of smith's dust were used in the great ornamental gardens across England, particularly parterre
gardens, also known as knot
or embroidery gardens. The smith's dust was spread over the soil under the flowers in the parterre. The dark color of the smith's dust was a perfect foil for the flowers above, emphasizing their delicate shapes and colors. In addition, the iron in the smith's dust provided important nutrients to the plantings as it slowly oxidized into the soil. When employed in this manner, smith's dust was also called "black earth."
Powdered iron can burn at very high temperatures and therefore smith's dust was an ingredient in a number of early gunpowder
recipes. Smith's dust was also a necessary component in making a smooth waterproof floor covering similar to cement, when it was mixed with slaked lime
, river sand and bullock's blood. This mixture was worked into the consistency of modern-day mortar. It was then smoothed over a foundation of stones or rocks to a thickness of about two inches and left to harden. Once this mixture cured, the floor was completely waterproof, according to period sources.
Smith's dust was available from nearly every blacksmith during the Regency and had any number of uses. One of those was to demonstrate the magnetic power of lodestones. There were man-made magnets available throughout the Regency, but they tended to have industrial or scientific applications and were seldom the personal possessions of gentlemen. Natural lodestones, particularly the spherical terrellae
in their ornate settings, were more likely to be found in the collections of gentlemen, and some ladies, of culture, particularly those with an interest in natural history or science. Anyone with a lodestone in their collection of curiosities would almost certainly have a small vial or box of smith's dust at hand to demonstrate the sphere's attractive power. Thus, lodestones and smith's dust were and are, a metaphor for romantic attraction.