For hundreds of years, large fossilized bones have been unearthed in Kentucky, just south of the Ohio River. Some of these bones eventually made it Monticello. Listen to learn how.

Kyle Chattleton: This is Mountaintop History, a podcast produced by the Thomas Jefferson Foundation at Monticello. 

Olivia Brown: Mountaintop History brings forward meaningful stories from this historic home and plantation — from the past and from the present.

Kyle Chattleton: My name is Kyle Chattleton. 

Olivia Brown: And I'm Olivia Brown.

Kyle Chattleton: Thank you for joining us. We hope you'll learn something new.

Olivia Brown: In the Entrance Hall of Monticello sit a collection of fossils from the Ice Age. For the past 200 years, visitors to Thomas Jefferson's home have marveled at the size of mastodon jawbones, mammoth teeth, and bones from animals like prehistoric bison and horses. These fossils and their history date back much farther, however; so, let's go back in time over 10,000 years. 

What's become known today as Big Bone Lick, Kentucky, dates back to the late Pleistocene epoch, what we often refer to as the Ice Age. Sulfur springs in the modern-day Ohio River Valley created a salt lick that drew megafauna like mastodons, mammoths, bison, ground sloths, and more. Much later on, this site became a rich area for fossil excavation, which drew many people who slowly unearthed fossilized bones over the course of 300 years starting in the 18th century. Today, Big Bone Lick is referred to as "the birthplace of American paleontology," because, unfortunately for those prehistoric animals, the salt lick created a marshy area around the spring where they got stuck and were unable to escape. 

Long before European colonists or American scientists and explorers came upon Big Bone Lick, it was a site known to Native Nations like the Shawnee and Lenni Lenape, or Delaware, peoples. The salt found at Big Bone Lick made it not only a place where animals often lived, but also became an important resource for human settlements. People like the Shawnee were collecting brine from the salt lick to supplement their diets, which at that point were more plant-based and lower in natural sodium. There are three different accounts recorded by Europeans or Americans who heard members of Native Nations talking about the bones from Big Bone Lick. Some referred to a "Great Buffalo," or another mighty beast sent by the "Great Spirit," or creator and protector of the world. Thomas Jefferson heard one such account sometime between 1775 and 1781 at a council with Lenape warriors. Jefferson wrote in his book Notes on the State of Virginia that the "chief speaker" spoke of a "tradition handed down from their fathers." This speaker said, "That in antient times a herd of these tremendous animals came to the Big-bone licks, and began a[n] universal destruction of the bear, deer, elks, buffaloes, and other animals which had been created for the use of the Indians." 

European colonists first explored Big Bone Lick in 1739 when French traders traveling the rivers sought to move against the Chickasaw Nation, who had previously disrupted French communications in the Lower Mississippi Valley. Baron Charles de Longueuil led an expedition through the Ohio River Valley into Chickasaw territory. When they arrived at the site of Big Bone Lick, Longueuil's men gathered fossilized bones they found there, and planted a French flag declaring the land as property of the King. Some of the bones collected were then transported across the Atlantic with Longueuil and placed in the collection of the French King, called the Cabinet du Roi. French scientists and zoologists examined the bones in the subsequent years and tried to figure out what kind of animal they may have come from. They suggested first, of course, that these were bones of a very large elephant, but others thought that some of the bones may be from gigantic hippopotamuses, buffalo, and rhinoceros, or even what they at that point called the Siberian mammoth. As the debates continued in France, others were traveling to Big Bone Lick, including more French traders and American colonists from Pennsylvania and Virginia. 

By the early- to mid-18th century, Europeans began displacing Native peoples from this area. The land itself first entered private hands when Thomas Jefferson, the sitting Governor of Virginia, approved a military grant for William Christian in 1779 as recognition for Christian's service in the Seven Years' War. The land changed hands many times, but this did not stop scientists, naturalists, and archeologists from visiting the area and excavating fossilized bones, sometimes without the express permission of the then owners of the land. It's possible that Jefferson himself learned about Big Bone Lick starting in the 1760s, as some of his contemporaries had either seen or owned bones that had been excavated there. In 1766, Thomas Jefferson went to Philadelphia to be inoculated for smallpox, but on the same trip he likely met Dr. John Morgan, a physician in the city. Morgan was part of an expedition to Big Bone Lick and brought home some of the bones he found. Morgan's expedition partner, George Croghan, then sent eight fossilized bones to Benjamin Franklin in London in 1767, when Franklin was serving as a colonial representative from the Pennsylvania Assembly. While we don't know for sure if Thomas Jefferson first learned of Big Bone Lick from Morgan, Franklin, or later on from the Lenape delegation, but it was clearly many years before his presidency. 

Jefferson's focused interest in Big Bone Lick began around 1780, when the Marquis Francois Barbe-Marbois, a member of the French Legation in Philadelphia, sent questionnaire surveys to each of the states the French were helping during the American Revolution. Thomas Jefferson, Virginia's Governor at the time, received this survey and began answering these questions. He then incorporated them into a book: Notes on the State of Virginia. In Query VI, Jefferson wrote about the "Mammoth, or big buffalo, as called by the Indians." He said it was the largest of Virginia's quadrupeds, and the "testimony of the Indians [is] that this animal still exists in the northern and western parts of America." Jefferson also used the size of the mammoth to refute the theory of American degeneracy. Scientists like Georges-Louis Leclerc de Buffon, a leading French naturalist who had written and published his own theories on the bones from Big Bone Lick, upheld the idea that animals in the "New World" were inferior to those of the "Old World." These theories tried to prove European superiority over former or independent American colonies, but Thomas Jefferson sought to disprove that. He did so in part through his book Notes on the State of Virginia, but then continued by bringing actual specimens to France, including a panther skin and the bones of an American moose. 

Over a decade after Jefferson published Notes, the American Philosophical Society created the "Committee to collect information respecting the past and the present state of this country" in 1799. The Committee's members included, among others, Thomas Jefferson, who was then the President of the American Philosophical Society; Dr. Caspar Wistar, the Society's Vice President; James Wilkinson, an Army Commander and later Governor of the Louisiana Territory; and Charles Willson Peale, the founder of the American Museum in Philadelphia. In a circular letter, the American Philosophical Society published a list of recommended duties of the Committee, with the very first being "To procure one or more entire skeletons of the Mammoth, so called, and of such other unknown animals as either have been or hereafter may be discovered in America." 

Charles Willson Peale wrote to Thomas Jefferson in the summer of 1803, informing him that a Cincinnati physician, William Goforth, had begun a new excavation at Big Bone Lick. Interested in what Goforth had found, Jefferson then asked Meriwether Lewis, who was on his way West to begin his expedition with the Corps of Discovery, to visit Goforth and examine the collection. Lewis met with Goforth and even went to the Lick to gather bones for President Jefferson. Whatever it may have been that Lewis collected did not make it to Jefferson, however; the boat carrying the shipment sank, so it and the bones ended up somewhere at the bottom of the Mississippi River. 

The Corps of Discovery, led by Meriwether Lewis and William Clark, completed their expedition to the Pacific Ocean and back by September 1806, but President Thomas Jefferson's interest in the fossilized bones of Big Bone Lick had not yet waned. The American Philosophical Society's Committee, that had been formed years earlier, was still hoping to assemble a full skeleton of what they called a mammoth, but we today know as a mastodon. In an effort to recover the remaining bones to complete the full skeleton, Jefferson organized an expedition to the Lick and put William Clark at its head. William Clark and his brother George Rogers Clark, who was a longtime acquaintance of Thomas Jefferson, arrived at Big Bone Lick in September of 1807. They hired men to help them dig and procured tools from nearby Cincinnati, just on the other side of the Ohio River. The excavations didn't start off quite as they planned, however. William Clark wrote to the President on September 20, 1807, saying, "I have been employed two weeks at this place with ten hands searching for the bones of the Mammoth &c. without meeting as much suckcess as I expected." He did persist and eventually collected hundreds of bones. In October, Clark selected 300 fossils to send to Jefferson in Washington, DC, from Louisville, Kentucky. Clark described some of what he collected in an accompanying letter: 

"The different bones which I have Collected in this serch, are those of the Mammoth, the Eliphant, Two non-descript animals of the Sheep and Goat species with horns bending down; the bones of one of those Animals much larger than those of their Class, the other small and May possibly be the female [...] I also found a Part of the head of an animal of the Buffalow or Cow Species [...] Several bones of the horse were found at some depth under the surface in a stiff mud." 

Though he had not yet received the bones from Clark, Jefferson determined that he wanted to distribute many of them to other repositories. In a letter to Dr. Caspar Wistar, who had been with Jefferson on the American Philosophical Society's Committee, Jefferson wrote, "the great mass of the collection are mere duplicates of what you possess at Philadelphia, of which I would wish to make a donation to the National Institute of France which I believe has scarcely any specimens of the remains of these animals." Approximately 300 fossilized remains of various prehistoric animals arrived in Washington, DC at the President's House on March 7, 1808, where the sitting President laid them out on the floor of what is now the White House's East Room. He invited Wistar to Washington, and the two men examined the bones and organized them into three collections. One collection would go to the American Philosophical Society in Philadelphia, another would go to the National Institute of France, and a smaller portion would enter Thomas Jefferson's private collection, as he had personally paid all the expenses related to the collection and transportation of the fossils themselves. 

After decades of debate among scientists around the world, there was finally consensus about the fact that one of the animals whose bones had been unearthed was not an elephant, not a hippopotamus, and not a Siberian mammoth. It received a new name - mastodon - and in an 1809 letter to Charles Willson Peale, from his new found retirement at Monticello, Jefferson wrote that this name "perhaps may be as good as any other, & worthy of adoption, as it is more important that all should agree in giving the same name to the same thing than it should be the very best which might be given." 

Big Bone Lick, Kentucky has captivated people for hundreds, if not thousands, of years. Native Nations called the area home, and the bones influenced their creation stories. European colonists excavated the land for decades in the mid-18th century. American archeologists, naturalists, and scientists continued to return to the Lick in search of information about its fossils. Even the President of the United States sought answers to the mysteries. Massive upper and lower jawbones of the American mastodon, unearthed by William Clark in Big Bone Lick, are still on display in Thomas Jefferson's home. All you have to do is visit Monticello to see them. 

This has been another episode of Mountaintop History, a collaboration podcast between WTJU and the Thomas Jefferson Foundation. 

Kyle Chattleton: Join us for new episodes every two weeks on Apple and Google Podcasts, Stitcher, and the Virginia Audio Collective.

Olivia Brown: To learn more about Monticello or to plan your next trip, visit us online at 

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