Return to homepage.


Wampum is, strictly speaking, a string of white beads, typically made from the shells of mollusks indigenous to the seacoasts of eastern North America (1). The beads were prized by North American Indians as ornament for the body or for weaving into fabric, and they were valued as "shell money" or "currency" in barter (1). It has been claimed that only the white beads are properly called wampum, but those made from the purple of clam shells have also been included, and with post-Columbian blue glass beads, they were even more highly prized (1-4).

Belts made from beads, known as wampum belts, were used on great ceremonial occasions, such as the making of treaties. They were used, rather than signed paper, to seal and solemnize events. The wampum-belt Web site shows such belts with beads woven into fabric. It also shows mollusks from which the white and purple shell-beads were derived, and teaches much about the use of beads in Indian culture. In (3) are fine pictures of beads and necklaces, which were made, not only from shell, but from slate, sandstone, steatite, bone, quartz, magnesite, tooth, copper, pottery, claws and nuts, and which originated from other places, including California, Oregon, Montana and Wisconsin.

That beads of various kinds have a rich history among very many cultures dating back to antiquity is evident from the title of (4). Even in North America at least eight thousand years before the white man, Indians were wearing and trading beads (4). The richness of relatively recent bead art is demonstrated in its sophisticated uses by North American Indians, such as in a saddle blanket and saddle; these are shown in beautiful colored pictures (4). Dubin's timeline for bead-making has glass beads entering North America with Christopher Columbus in 1492 as gifts for the native population. "Most of the beads introduced to the New World by Europeans were made of glass, a material unknown to the native cultures." She tells us that glass beads from European producers of Venice especially, but elsewhere too, became objects of barter for furs in the west.

Dubin (4) gives the technical background of the bead industry, which very much figured in an extended marketplace through much of recorded history, including that of the various tribes of inland North America under European influence. The first known large-scale manufacture of glass beads was in Egypt in about 1400 B.C. These beads were sometimes quite complex and made to replace precious stones. The practice of cutting beads and making holes with bow drills and abrasive slurries is also quite ancient, though tedious.

Glassmaking is an ancient art as well ( ), involving heating and melting raw materials from the earth to a molten, viscous or taffy-like liquid ( ). The liquid can be formed into various shapes in this "taffy" state, including, in the modern world, flat sheets, fibers, vessels, and light bulbs. The different shapes are often accomplished today by: floating the melt on a molten tin bath (flat sheet); by pulling it through holes in a platinum bushing (fiber); by molding it on the outside while puffing air within (vessels and light bulbs). Forming the right shape requires being at the right viscosity, and therefore the right temperature.

Viscosity is a property of all fluids, including melts, which generally decreases continuously with increasing temperature. It is a measure of resistance to change of form. The viscosity of water near room temperature (20° C) is one centipoise. For all glasses, the softening point is designated as the temperature at which a glass fiber of the particular glass composition will deform under its own weight under certain specified conditions (5). This corresponds to a viscosity that is about 10,000,000,000 or 1010 centipoises. Most commonly used glasses are above 600 to 700° C at this point (5).

Essentially, the same "melting" art that was used to make glass beads is used to make window glass, bottles and incandescent light bulbs today, although with much more automation, attuned to a commodity article. Forming, of course, is different in each case, and different from historical bead-forming as well. All these modern glasses are generally made of "soda-lime-silica" compositions, the most commonly used composition of our day. For the float glass that is used for windows, the composition contains about 73% SiO2 or silica, added as relatively iron-free sand, 14% Na2O or sodium oxide, and 9% CaO or calcium oxide, plus other minor constituents. The soda (Na2O) and lime (CaO) are added to the glass batch mostly as carbonates, which serve the function of fluxes, or melting aids, especially so in the case of sodium carbonate. Without fluxes to dissolve the sand grains during melting, sand melting by itself would require temperatures much above the typical maximum of 1400-1500° C.

So, glassmaking is not simple melting. Simple melting of sand, or quartz, occurs sharply at 1610° C, while anhydrous Na2CO3 melts sharply at 851° C. The low melting sodium carbonate initiates an active solution for dissolving sand grains, so the "melting" process overall is not dependent on true melting of refractory sand. For the material scientists that work with glass today, the melting process itself is fascinating chemistry at high temperature. The soda-lime-silica composition with which they deal derives from balancing the ease of melting/solution, compatibility with furnace refractory bricks, and acceptable product properties for the marketplace.

For bead-making, glass composition was variable, depending on the desired bead opacity, color, and special aesthetic effects. However, the host composition appears to have been based on the use of sand and alkaline oxides of Na2O or K2O, whichever was most readily obtained (4).

The well known glassmaking of Venice began in the period of 1200 to 1400. The environment in which this happened has been described by Dubin (4). All manufacture was centralized in 1292 on the island of Murano, although Venetian bead "workshops" did appear in other countries. Centralization of manufacture was meant to protect trade secrets and to contain the inevitable fires from the use of very hot furnaces. Competitors' factories grew up in Holland, Moravia, and Bohemia. Each emphasized its own technique for forming the glass: (a) winding the molten glass onto a metal wire; (b) drawing hollow canes; (c) molding in bulk form for simplified fabrication of intricate designs; (d) blowing. Venetian glassmakers had reinvented the drawing of hollow canes by about 1490, thereby eliminating the need to bore holes by drilling. They trapped an air pocket into the glass and then elongated the glob; the air pocket became axially elongated too. Winding, also practiced by Venetian glassmakers, eliminated drilling as well, but it was still more tedious than drawing hollow canes.

"By the eighteenth century, Venice had a near-monopoly on the glass bead market." In 1764 twenty two of its manufacturers produced 44,000 pounds of glass beads, but with Napoleon Bonaparte's fall in 1797 Venetian glassmaking suffered a setback, temporarily (4). It must be assumed that from this dominating Venetian industry, even in temporary decline, or perhaps from its imitators, did come at least some of the trade glass beads purchased by Meriwether Lewis in Philadelphia in 1803.

In the respect that the Lewis and Clark Expedition was about establishing claim in the Louisiana Purchase lands for commerce over European competition, it was entirely about gaining the fur trade of the west for the United States (2,4). Thus, Meriwether Lewis and William Clark carried with them glass beads, among many other items, to show off their country's trade wares, and to use them in barter with Native Americans (2,6). Such items were no longer being used simply as gifts.

Lewis and Clark were at this point in history, however, not yet up to trading for animal furs of commerce, but, typically, for food and other articles needed by the vulnerable Corps of Discovery; there were hungry circumstances (2). At Fort Mandan, during the cold winter of 1805, axes made on site were traded for corn. Preparing to cross the Bitterroot Mountains outbound, the Corps traded dearly for horses, some of which became meat for the men in difficult winter travel. On the return trip, the men traded what they had left, namely awls, knitting pins, needles, vermilion, thread and ribbon, for roots only.

Along with beads, Lewis stored up on many other items in Philadelphia for shipment by wagon to Pittsburgh, and later in St. Louis too, which were intended for use as "coin" of the west. These included scissors, thimbles, sewing thread, awls, knitting pins, needles, calico, mirrors, brass buttons, silk, face paint and vermilion, knives, tomahawks, axes, razors, ivory combs, arm bands, tobacco, whiskey, medals, flags, brass kettles and ear trinkets (2). All were packed in 21 bags, each of these meant for a specific tribe that Lewis expected to encounter (2).

This was the currency of trade with all the Indian nations of the Louisiana Purchase lands, whose acquisition Thomas Jefferson engineered in early 1803, even as he and Lewis were planning the Lewis and Clark Expedition. They had a very good idea of what served as "currency" in the vast new land being obtained from Napoleon Bonaparte, even if its borders were yet fuzzy, just as they understood well the favorable circumstances for purchasing Louisiana just then (7). At this time the French leader was in need of cash as he prepared for war with England. Moreover, France could not police its ownership of Louisiana, and probably preferred, between England and the United States, that the latter prevail in North America.

What was the customary currency elsewhere? Paper money was common in China by the 14th century (8). The Massachusetts Bay Colony was the first to issue paper money in the colonies, in 1690, followed thereafter through the 18th century by various states (8). In the late 17thcentury, Virginia tobacco business was conducted with warehouse receipts rather than hard money. Such practices evolved to the commonplace "bills of credit" in the colonies, while England steadfastly prohibited the minting of coin (9). Before the Revolutionary War had ended, however, Robert Morris, appointed in 1781 as superintendent of finance by Congress, founded the Bank of North America and put the United States on hard currency.

So, North America at the time of the Lewis and Clark Expedition had two economies. Lewis made his purchases on the basis of one [a $1000 War Department draft in Philadelphia (10)], then, for the most part, left his white man's "wampum" behind, and went forth with the other. Compared to exchanges in a paper economy, the stocking-up preparations took much more attention to detail, and added burden to the keelboat in Pittsburgh. However, he could not have otherwise succeeded.

Inquiry project: How would you proceed to plan an expedition in space to another planet, knowing that this planet is inhabited, so as to have the appropriate currency?

Wampum References

1. Harris, William H. and Levey, Judith S., eds., The New Columbia Encyclopedia, New York:
    Columbia University Press (1975).

2. Ambrose, Stephen E., Undaunted Courage, New York: Simon & Schuster (1996), pp. 84, 88, 155,     179, 185, 198-99, 254, 355.

3. Miles, Charles, Indian & Eskimo Artifacts of North America, New York: Bonanza Books (1963),
    pp. 134-143.

4. Dubin, Lois Sherr, The History of Beads from 30,000 B.C. to the Present, New York: Harry N.     Abrams, Inc., Publishers (1987), pp. 43, 106-111, 186-187, 261-290, 344.

5. Shand, E.B., Glass Engineering Handbook, 2nd ed., New York: McGraw-Hill Book Company     (1958), pp. 16-21.

6. Ronda, James P., Lewis and Clark Among the Indians, Linclon, NB: University of Nebraska Press     (1984), p. 9.

7. Malone, Dumas, Jefferson the President: First Term, 1801-1805, Vol. 4 of Vols. 1-6, Boston:
     Little, Brown and Company (1970), pp. 284-310.

8. Hunter, Dard, Papermaking, New York: Dover Publications (1978), pp. 204, 483.

9. Morison, Samuel Eliot, The Oxford History of the American People, New York: Oxford University     Press (1965), pp. 87-88, 143-145, 230.

10. Cutright, Paul Russell, Lewis & Clark: Pioneering Naturalists, Lincoln, NB: University of
      Nebraska Press (1989), p. 27.


Pittsburgh Perspective Staging Point Keelboat  Corps of Discovery  Latitude and Longitude  Medicine  Scientific Enterprise Wampum  Maps Main Event  Biology  Pittsburgh Geology  Education 

Contact Information    © Copyright Information  Home
BACK TO TOP Pittsburgh As Frontier Gateway in 1803 and Staging Point A Lewis and Clark Pittsburgh Perspective The Main Event Learn about the Keelboat The Corps of Discovery Learn about Latitude and Longitude Medicine on the expedition Scientific Enterprise Wampum was the currency on the expedition Mapping the expedition Smithsonian Flora Preservation Link to education site Pittsburgh Geology Return to main page