MS.Add.5140: Architectural notes, in English and Latin, c. 1875, 291 folios, including: (fos 178-84) notes by Robert Willis on London buildings; (fo. 195) a letter from H.R. Nevill to Mrs Almira Heaviside, 1 May 1875; (fo. 225) an incomplete letter from an unidentified correspondent to Stewart, 5 May 1875.
MS.Add.5145: Notes on woodwork, mid-19th century, 261 folios. Several folios are in the hand of Robert Willis.
MS.Add.5146: Notes for a proposed book on woodwork and ironwork, 1882-1889, 79 folios.