Thomas Jefferson was fascinated by fossils. There are several accounts of his asking Meriwether Lewis, William Clark, and George Rogers Clark to search for fossils for him at Big Bone Lick in Kentucky, and some of the items he collected are on display at Monticello to the present day. However, Jefferson was not just a collector. He was a practicing field archaeologist.

From a young age, Jefferson was intrigued by the Monacan Indians he saw around his childhood home in Albemarle County, Virginia. He wrote about a party of Indians who passed through his father’s property at Shadwell and to visit an earthen mound nearby. The Indians lingered at the mound for some time, and young Jefferson noted their mournful expressions, “which were construed to be those of sorrow.” Jefferson drew the conclusion that the mound was a burial ground, perhaps of ancient origin, and that the Monacan Indians were visiting the mound to grieve.

Intrepidly curious, Jefferson noted a number of other mounds (or “barrows,” as he called them) around the area that he suspected contained human remains. In the 1770’s, when he was in his late 20s or early 30s, he decided to investigate one on a hill in the Blue Ridge Mountains, at a location near Monticello he described as “a few miles north of Wood’s gap.” There he conducted an extensive and scientifically ambitious archaeological dig. Jefferson wrote about what he found in Notes on the State of Virginia in 1787:

… many [barrows] are to be found all over this country. These or of different sizes, some of them constructed of earth, and some of loose stones. That they were repositories of the dead, has been obvious to all: but on what particular occasion constructed, was matter of doubt. Some have thought they covered the bones of those who had fallen in battles fought on the spot of interment. Some ascribed them to the custom, said to prevail among the Indians, of collecting, at certain periods, the bones of all their dead, wheresoever deposited at the time of death. Others again supposed them the general sepulchers for towns, conjectured to have been on these grounds; and this opinion was supported by the quality of the lands in which they are found (those constructed of earth being generally in the softest and most fertile meadow-grounds on river sides) and by a tradition, said to be handed down from the aboriginal Indians, that, when they settled in a town, the first person who died was placed erect, and earth put about him, so as to cover and support him; that, when another died, a narrow passage was dug to the first, the second reclined against him, and the cover of earth replaced, and so on. There being one of these in my neighbourhood, I wished to satisfy myself whether any, and which of these opinions were just. For the purpose I determined to open and examine it thoroughly. It was situated on the low grounds of the Rivanna, about two miles above its principal fork, and opposite to some hills, on which had been an Indian town. It was of a spheroidical form, of about 40 feet diameter at the base, and had been of about twelve feet altitude, though now reduced by the plough to seven and a half, having been under cultivation about a dozen years. Before this it was covered with trees of twelve inches diameter, and round the base was an excavation of five feet depth and width, from whence the earth had been taken of which the hillock was formed. I first dug superficially in several parts of it, and came to collections of human bones, at different depths, from six inches to three feet below the surface. These were lying in the utmost confusion, some vertical, some oblique, some horizontal, and directed to every point of the compass, entangled and held together in clusters by the earth. Bones of the most distant parts were found together, as, for instance, the small bones of the foot in the hollow of a scull; many sculls would sometimes be in contact, lying on the face, on the side, on the back, top or bottom, as, on the whole, to give the idea of bones emptied promiscuously from a bag or a basket, and covered over with earth, without any attention to their order. The bones of which the greatest numbers remained, were sculls, jaw bones, teeth, the bones of the arms, thighs, legs, feet and hands. A few ribs remained, some vertebrae of the neck and spine, without their processes, and one instance only of the sacrum bone which serves as a base to the vertebral column. The sculls were so tender, that they generally fell to pieces on being touched. The other bones were stronger. There were some teeth which were judged to be smaller than those of an adult; a scull which, on a slight view, appeared to be that of an infant, but it fell to pieces on being taken out, so as to prevent satisfactory examination; a rib and a fragment of the under jaw of a person about half grown; another rib of an infant; and a part of the jaw of a child, which had not cut its teeth. This last furnishing the most decisive proof of the burial of children here.

Caught up in the spirit of scientific inquiry, Jefferson appears to have felt no squeamishness or sentiment about digging into a human grave. From a scientific standpoint, he found the presence of children’s bones in the barrow particularly significant. “Every one will readily seize the circumstances above related, which militate against the opinion that it covered the bones only of persons fallen in battle,” he wrote. Also, the jumbled arrangement of the bones also seemed to rule it out as being common sepulcher of an Indian town, in which bodies were generally placed upright, touching one another other. He determined to investigate further.

I proceeded then to make a perpendicular cut through the body of the barrow, that I might examine its internal structure. This passes about three feet from its center, was opened to the former surface of the earth, and was wide enough for a man to walk through and examine its sides. At the bottom, that is, on the level of the circumjacent plain, I found bones; above these a few stones, brought from a cliff a quarter of a mile off, and from the river on eighth of a mile off; then a large interval of earth, then a stratum of bones, and so on. At one end of the section were four strata of bones plainly distinguishable; at the other, three; the strata in one part not ranging with those in another. The bones nearest the surface were least decayed. No holes were discovered in any of them, as if made with bullets, arrows, or other weapons. I conjectured that in this barrow might have been a thousand skeletons.

Jefferson concluded that “appearances certainly indicate that it has derived both origin and growth from the accustomary collection of bones, and deposition of them together.” He conjectured that “the first collection had been deposited on the common surface of the earth, and few stones put over it, and then a covering of earth, that the second had been laid on this, had covered more or less of it in proportion to the number of bones, and was then also covered with earth; and so on.” In other words, the barrow consisted of a number of mass graves, slowly added to and built up over time.

In his methods and observations of the archaeological strata, Jefferson displays his characteristic brilliance. His conclusions about the mounds were worlds ahead of the general state of archaeological science at that time, and have been borne out by more modern scientific investigation of similar burial structures. As Silvio Bedini writes in his monograph Jefferson and Science, “By applying his innate sense of order and detail, he anticipated modern archaeology’s basis and methods by almost a full century.” The dig also demonstrated Jefferson’s intense interest in–and unsentimental view of–Native American cultures.