The library was particularly important to Robert Fellowes. Its location varied in the several alternative ground floor plans made for him by Soane but was usually on the west side of the house. Here it is also sited to the west and lit by one of the two tripartite windows of the south elevation. An earlier design is referred to by Soane and drawing 23 presumably represents that design but with the addition of pedimented bookcases, fronted by marble-topped tables, between the windows. A problem with maintaining the symmetry of the panelling was resolved by making the doors of varying widths. Soane notes of these doors that the 'Magazins' are to be 4½ and 2½ inches wide. These magazin[e]s labelled 'E' and 'F' appear to be the rails and stiles enclosing the panels. None of the the architectural dictionaries (including W. Papworth, editior for the Architectural Publication Society's, Dictionary of architecture, 1848-92) offer a defInitions for 'magazine' other than as a store, wardrobe, reservoir etc.
Drawing 24 does away with bookshelves enclosed by doors as well as the bookcases between the windows and the result is more harmonious. A further improvement was made on drawing 25 with the end walls made symmetrical with matching doors (one to a closet) and with the same bead moulding describing an arc above the shelves.