Thanks for looking, Sue. He is named Grundy on the IGI for his birth and marriage and also I have his death certificate so I am pretty sure it's the right name. I know from the IGI that he had a daughter, named Mary Chadwick. I have found his daughter in law Mary Chadwick with Grundy's son (hopefully) James living at 251 Bengall Street Manchester in 1851. I wonder if you can see if they were on the Index for 1841. James Chadwick was born c1817 in Bolton, Mary also c1817 in Bolton children would be John (1837) and James (1839) both born in Bolton. subsequent children were born in Manchester after 1841 James was an Engineer
I really am grateful for your interest
Val