Entering "Castler%" will return all placenames starting with "Castler", for example:
Entering "Bal%agh" will return all placenames starting with "Bal" and ending with "agh", for example:
Entering Bal_agh will return:
You should remember that consonant sounds are less likely to have changed over the years than vowel sounds.
The same principles as above hold true for the advanced search, but you can also restrict the search area to a county or, if you know them, the
parish or poor law union. The fewer matches you have the more likely you are to be able to identify the relevant one.