Bottom line is that he got it right most of the time, but not always. He has Oxford and Cambridge data in at times and Oxford has a slight urban warming bias for some decades between 1881 and 1940. No-one knows how Manley did it or what series he used. Just documenting it all for posterity would be good !
Flashback: Email 4709, Phil Jones, Nov 2007, urbanization shmurbanization?: "There are no corrections/adjustments for urbanization applied...There are several papers in th IPCC WG1 Ch3 that show that urbanization isn't an issue"