Christopher Blackett (1751-1829) Squire of Wylam, Northumberland, 1800-1829. The original is in the Science Museum collection; the volume with the reproduction is in the collection of the North of England Institute of Mining and Mechanical Engineers and has been used with their permission. The portrait clearly dates from before the subject's death in 1829; had the author lived another 100 years, the copyright on the portrait would have expired in 1999.