The first indications that terras roofs were installed in ca. 1812 were found in the drawings and engravings made of Montpelier before President Madison's death in 1836.  These images clearly showed that the wings were covered with flat, or almost flat, roofs and enclosed with a Chinese rail.  Because both flat roofs and Chinese rails were typical features of Jeffersonian designs, it was assumed that terras roofs covered the wings.  Additional documentation for Montpelier's terras roofs was found in a letter sent to President Madison from his carpenter James Dinsmore.  The letter included a reference to iron plates that were being sent from Washington for use on the wing roofs.  Because iron plates were occasionally used to weatherproof terras roofs, the letter was an important piece of evidence.  However, there was not enough information in these documents to develop designs for the reconstructed terras roofs and at the start of the Restoration no physical evidence for the terras roofs had been found.