For example, Ian Rawes has scanned and stitched together individual sheets of Thomas Milne's land use maps (1800) and map tiled them. He has used modern physical reproductions of out of copyright maps. If we vectorise his digital reproductions and thus create new layers, to which we may further manipulate and modify, are these clearly derivative works, and what is the copyright position on these possibly derivative works. Ian's digital copy was probably made from a physical copy of the London Topographical Society's physical reproduction. https://catalyst.library.jhu.edu/catalog/bib_2028331; http://www.londontopsoc.org/regency1
British Library
See: The British Library has one sheet georeferenced and digitised, showing the west and south-west of the city. Shelfmark: Shelfmark: Maps.Crace XIX; Item no.: 28; Length: 432; Width: 508; Scale: Muillimetres; Genre: Map; Map scale description: No scale given. http://britishlibrary.georeferencer.com/map/HuTnS43MpEwwC2Og1FI9bc/201311061938-ylmNan/visualize
It is described as "MILNE'S PLAN of the CITIES of LONDON and WESTMINSTER, circumjacent TOWNS and PARISHES &c. laid down from a TRIGONOMETRICAL SURVEY taken in the YEARS 1795-1799". Attached metadata notes state "This is one of six sheets forming Milne's map of the area twenty miles around London. It was the first to make use of the 'Trygonometrical Survey' founded in 1791.
This sheet covers the area to the west and south-west of the capital. It shows all the field boundaries and indicates land use with a complex system of letters and colours. The key is featured on the top corners. The borders of the map are divided in minutes and seconds, giving scale, angles of observations and magnetic variations. Thomas Milne trained as an estate surveyor and worked on the first Ordnance Survey map of Kent."
London Sound Survey
See South East sheet: http://www.soundsurvey.org.uk/index.php/survey/historical_london_map/milne_1800/2147/
Royal Collections/Royal Museum Greenwich
The Royal Collections has a digitisation of a C20th reproduction of Thomas Milne's Land Use Map of London and Environs in 1800. after drawing of 1800, Introduction by G.B.C.Bull on 5 pages. 6 illustrations and maps (numbered in parts). Inclosed in brown folder. Original in British Library. RCIN 702193. This reproduces text and six colour map images. The digital images assert "Royal Collection Trust/© Her Majesty Queen Elizabeth II 2017": https://www.royalcollection.org.uk/collection/702193/thomas-milnes-land-use-map-of-london-and-environs-in-1800