Jefferson had long been obsessed with the question of how the Indians came to North America and had spent years compiling lists of words commonly used in Indian languages and dialects. His theory was that similarities between words from the Old and New World might offer a clue to the Indians’ origin.

Jefferson had shamelessly exercised his presidential power in pursuit of his obsession. He had once invited five Cherokee chiefs to a White House reception and quizzed them about their language. He had instructed Meriwether Lewis to collect vocabularies from the Indians the explorer encountered on his historic journey to the Pacific Ocean.

The book Jefferson planned to write on the origins of the Indian would be the culmination of his intellectual career. The tumultuous events of his second term had temporarily stalled the project, and he had put off sending the lists to the printer until he could write digests of the reams of new material Lewis and Clark had brought back from their trek.

Vowing to tend to the task as soon as he was back at Monticello, he stacked the papers into a neat pile, tied it with string, and placed it with the other vocabularies and stationery in a sturdy trunk. It would be transported with his belongings to the James River and loaded onto a boat that would take his baggage to Monticello. He placed the last packet of documents in the trunk and snapped the cover shut.

His desk was clear now except for a pewter box that had his name embossed on the lid. The president opened the box and removed a rectangular piece of vellum about ten by twelve inches in size. He held the soft animal hide close to an oil lamp. The pebbled surface was covered with strange writing, wavy lines, and Xs. One edge was ragged.

He had acquired the vellum in 1791. He and his Virginia neighbor “Jemmy” Madison had ridden on horseback to Long Island, New York, to meet some impoverished remnants of the Unkechaug tribe. Jefferson had hoped to find someone who knew the ancient languages of the Algonquin tribe, and, in fact, three elderly women could still speak the old language. Jefferson had compiled a glossary from them that he hoped would help prove his thesis about the European origin of the Indians.

The chief of the tribe had presented Jefferson with the vellum, saying it had been passed down from generation to generation. Touched by the gesture, Jefferson had asked a rich landowner and fellow signer of the Declaration to provide for the Indians.

Looking at the vellum now, an idea occurred to him. He took it over to a table, where a horizontal wooden easel had two pens suspended from a framework that allowed them to move simultaneously. Jefferson regularly used this copying machine, known as a polygraph, for his voluminous correspondence.

He copied the vellum markings and added notes asking the recipient to identify the language in which the words were written. Then he addressed and sealed the envelopes and placed them in a basket for outgoing mail.