A new analysis of Dunlop's double star catalogue is now available.
Assessment of the accuracy of measures in the 1829 southern double star catalogue of James Dunlop
Roderick R Letchford, Graeme L White, Carolyn J Brown
Monthly Notices of the Royal Astronomical Society, Volume 510, Issue 4, March 2022
https://academic.oup.com/mnras/artic...584?login=true