update .....
the isaac and james Ormerod were not twins , they may not even be related , i was looking for the wrong people , My isaac and James's parents did not marry until after they were born in 1857, i should have been looking for isaac and james WALTON , which i now have found , isaac born in 1853 and james born in 1855, both in Padiham , Burnley.Thanks to those who contributed
mary and alice's birth certificates are on the way to me , which will confirm they were twins