John and Nan's route follows the line of the modern A62. There was a Robin Hood pub in Newton Heath; now apparently closed. At the time of writing (2019) The Crown and Kettle still stands at 2 Oldham Road.
No record a 'Nag's Head' pub in Oldham has been found
The infirmary clock was lit by gas sometime before 1825.
Worthington, Barry. Discovering Manchester: A Walking Guide to Manchester and Salford (Manchester, Sigma Leisure, 2002) p90