Several Mastodon bones, including an ulna (partially on far right) ©Thomas Jefferson Foundation at Monticello

Excavated: 1807

Origin: Big Bone Lick, Kentucky

Dimensions: 63.5 × 27.9 × 21.6 (25 × 11 × 8 1/2 in.)

Owner: The Academy of Natural Sciences

Historical Notes: Inspired by Jefferson's presentation of the Megalonyx bones, the American Philosophical Society formed a committee, headed by Jefferson with Charles Willson Peale and Dr. Caspar Wistar as members, whose mission was "to collect information respecting the past and present state of this country." In a circular letter sent out by the committee in 1798 to "lovers of science," the first item on a list of priorities was "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." The Great Salt Lick on the Ohio, known as Big Bone Lick, was a rich site for fossil finds. Jefferson probably knew Big Bone Lick as early as 1766 when he met Dr. John Morgan in Philadelphia who had collected "mammoth" (now known as mastodon) specimens from it. He also described the ancient salt lick, now in Kentucky but originally part of Virginia, in Notes on the State of Virginia.[1]

As president of the United States, Jefferson established the same objective for the explorers Meriwether Lewis and William Clark's expedition to the Northwest as that held by the American Philosophical Society: Learn more about all aspects of America. One of Meriwether Lewis's stops on the westward journey was at Cincinnati, Ohio, where he sent a group of Big Bone Lick fossils to Jefferson (which were lost in transit) and wrote a detailed report of Dr. William Goforth's excavation of the Lick.[2] The return of the explorers in 1806 provided another opportunity for gathering fossils for the Society. Jefferson financed William Clark's return to Big Bone Lick in 1807,[3] to collect mostly head and foot bones missing from the Society's "mammoth" skeleton that Charles Willson Peale was assembling.[4]

Clark's dig was an immense success. It netted over 300 bones of various species, included the coveted "mammoth" cranium. The bones were sent to Jefferson at the President's House. The sheer volume of the collection gave Jefferson the idea to send duplicate specimens to the National Institute of France.[5] He enlisted his old friend Dr. Wistar to come from Philadelphia to assist in the selection process.[6] With bones spread out in the rooms of the President's House, Wistar spent the early part of July 1807 writing a report on the collection and selecting the contents of three boxes to be sent to France. There the fossils became part of the Museum of Natural History, where they became critically important to the study of paleontology in France.[7]

The remainder of Jefferson's collection was divided between the Society and Monticello, where the fossils were displayed in the Entrance Hall. "There is a tusk and a femur which Genl. Clark procured particularly at my request for a special kind of Cabinet I have at Monticello," Jefferson wrote to Wistar.[8] Visitors to Monticello recorded seeing upper and lower jawbones, tusks, thigh bones, a head, and teeth of the "mammoth" in particular, as well as bones from other animals as well as petrifications.[9]

After Jefferson' death the Monticello collection was transferred to the University of Virginia, where it was first exhibited in the Rotunda. The American naturalist Richard Harlan recorded seeing the collection in 1831, and that same year one fossil from the university was lent to the American Philosophical Society for study there.[10] No record of the fossil collection at the university exists after 1848 and many surviving specimens today remain unidentified.[11]

The specimens given to the American Philosophical Society were transferred to the Academy of Natural Sciences in Philadelphia in 1849, where over fifty bones from Jefferson's collection remain today.[12]

- Text from Stein, Worlds, 400-02


  1. ^ Notes, ed. Peden, 43-44.
  2. ^ Lewis to Jefferson, October 3, 1803, in PTJ, 41:463-68. Transcription available at Founders Online.
  3. ^ Jefferson's memorandum book entry for February 9, 1808, records a payment of $199.66 for Clark's dig. MB, 2:1219. Transcription available at Founders Online. See also Jefferson to David Ross, February 24, 1807, Tucker-Coleman Papers: Series 2 Thomas Jefferson Correspondence, Special Collections Research Center, Earl Gregg Swem Library, College of William and Mary. Recipient's copy available online at the William & Mary Digital Archive. Transcription available at Founders Online.
  4. ^ Peale's Mastodon is discussed in Charles Coleman Sellers, Mr. Peale's Museum (New York: W.W. Norton & Co., 1980), 123-58.
  5. ^ Jefferson to Clark, December 19, 1807, in L&B, 11:404-05. Transcription available at Founders Online.
  6. ^ For more information see Howard Rice, "Jefferson's Gift of Fossils to the Museum of Natural History in Paris," Proceedings of the American Philosophical Society 95 (December 1951): 597-627.
  7. ^ Ibid., 620-21.
  8. ^ Jefferson to Wistar, December 19, 1807, Thomas Jefferson Papers, Library of Congress. Polygraph copy available online. Transcription available at Founders Online.
  9. ^ Several visitors to Monticello, such as Baron de Montlezun and Lt. Francis Hall, mention seeing Mastodon bones in the Entrance Hall. Montlezun and Hall's visits are included in Peterson, Visitors, 68-69, 74.
  10. ^ Richard Harlan, Medical and Physical Researches (Philadelphia: Lydia R. Bailey, 1835), 409University of Virginia Board of Visitor's Minutes, July 19, 1831, vol. 1, 260, ViU. Isaac Hayes published a paper on the Society's bones including the specimen from the University of Virginia in the 1834 volume of the Society's Transactions.
  11. ^ Board of Visitor's Minutes, vols. 1-3, University of Virginia.
  12. ^ Silvio A. Bedini, Thomas Jefferson and American Vertebrate Paleontology, Virginia Division of Mineral Resources, Publication 61 (Charlottesville: Department of Mines, Minerals and Energy, 1985), 17.