Robert Self is the conservator of architecture and furniture for Monticello, Thomas Jefferson’s home in Charlottesville, VA. His responsibilities are varied and include direct involvement with architectural restoration projects, research and writing, consulting, conservation of original pieces of Jefferson furniture, building reproductions and also, on occasion, crafting interpretive pieces.

His duties sometimes go beyond furniture manufacturing. One unusual project was making a replica for the Monticello Visitors Center of a moldboard plough designed by Jefferson. “Many people think that Thomas Jefferson was a great inventor,” Self says. “But his design for a moldboard is recognized as one of his only true inventions.”

The plough’s wooden moldboard lifts the soil that is cut by the metal plowshare and turns it over. Jefferson devised a mathematical and readily repeatable means of laying out and cutting what he referred to as his “moldboard of least resistance.” His design was, in part, inspired by a competition with the French to see who could develop the most efficient plough.

For the moldboard, Self needed a piece of timber 3-feet long by 12 inches by 13-1/2 inches and, to minimize checking, it had to be clear of the pith or heart of the tree. After calling suppliers all over the East coast, a piece with these specifications was finally found at a nearby sawmill.

This project introduced Self to the experience of working with green wood, as the plough-makers during Jefferson’s time presumably had to do. Each night he had to drape the wood in wet cloths to minimize checking. “A year after it was completed I had to readjust the hardware and replace the vertical ‘standard’ or support member because of moldboard shrinkage,” he says.

In 1993, Monticello launched an exhibition to celebrate the 250th anniversary of Jefferson’s birth in 1743. The exhibit included the return of several pieces of Jefferson furniture that are owned privately for a one-year loan period. With the permission of the owners, Monticello had Self reproduce some of them for display in the house after the originals were returned.

Among them is a gilded pier-mirror Jefferson purchased in France around 1789. It measures 69-3/4-inches tall by 43-1/2-inches wide.

All details of the original mirror were duplicated exactly. The white pine frame was routed out for the side-lights of glass, leaving strips in between where carved mouldings would be attached. The 1/2-inch backboards were put into a rabbet on the back of the frame. The mirror glass was put into place and then the carved mouldings were installed. The mouldings lap over the mirror glass, holding it in place. Custom mirror glass was selected to match the appearance of mercury-silvered glass as closely as possible.

An example of a more interpretive, rather than literal, reproduction is a mahogany architect’s desk with leather writing surface. “On occasion”, Self explains, “the house-joiners at Monticello copied pieces for Jefferson that he had purchased elsewhere.” The Monticello-made pieces are invariably a bit different in some respects, although it is usually obvious what the design source was.

“The desk I made is closely based on a French piece Jefferson purchased around the same time as the mirror,” Self says. However, the complicated mechanical mechanism for raising and lowering the writing surface on the French piece was simplified, based on other pieces made by Jefferson’s workmen, and solid wood was used instead of veneer.

“My intent with the piece was to create it in the same spirit as furniture originally made in the Monticello joinery,” Self says.

A replica of a mahogany architect’s desk with leather writing surface. Photo by Robert Self, courtesy of the Thomas Jefferson Foundation Inc.