Edward Derby

[aghadowey]

Did lots of searches at this site - https://thecore.com/seanruad/ - (with or without Antrim as county, using parts of the word to search, etc.) and didn't come up with anything that seemed to match the townland exactly. I think it does look like Kishandon (beginning with a K rather than an H).
However, I am offering this as a possibility to investigate further-
Cushdendun on the northeastern coast of Antrim- Culfeightrin Civil Parish, Poor Law Union/Registration District of Ballycastle.
https://www.townlands.ie/antrim/cary/culfeightrin/cushendun/

Now, if it is Cushendun that could mean the village or a place outside the village as well as within the townland boundaries.

The (free) online Catholic Parish register for Cushendun R.C. Parish (different than civil parish) only starts in 1862-
https://registers.nli.ie/parishes/0409
However, there are earlier records (from 1848) available-
https://www.johngrenham.com/records/rc_church.php?churchid=0409&parish=Cushendun

[Kiltaglassan]

You've played a 'blinder', aghadowey 



Added: https://idioms.thefreedictionary.com/play+a+blinder

[blinder]

Thankyou for your effort aghadowey. I have leads which I will pursue. Cushendun looks prospective to me, but I have not found Derby as a name in the area yet.
Johnston Derby wife is Janet and it looks like Downer on Edward's marriage certificate. Is Downer an Irish name?
Blinder