To this day and for as long as I can remember those who have taken the gentility pronounce Cassillis as Castles while we of the peasantry pronounce it as Caasseelis,

In another thread {WDLNGP} I gave two examples of folk memory being proved correct, I give another two :----
Looking down the brae from my back window I see the farm of "Brownmuir" known to the owners and locals as "The Brimmer". On looking up the 17th. C. map you will find "Brimmer" with no mention of "Brownmuir" so we have nearly 500yrs, and who knows how long before the date of the map, of folk memory on our doorstep.
To the East we have the croft of "The Lowes" {pronounced Lous} as it is called locally, again "correct" people call it "Lowhouse" with what authority? as it appears on the same map as "Lowes".
Interestingly enough we find the same word "Lowes" in the song "The Bonny Lass O Fyvie" it being pronounced the same as here with the Ou sound as in plough.