While not having been a contributor to this thread to now I would like to include some work done on the history of the name Qualtrough... not by me however.

While not as extensive perhaps as the work done by Greg and others on Kaighin, all helps on gathering information on Manx surnames as Nigel said.

It can be found at the following link.. the article by James Linton (September 1983) was also published in an IOMFHS Journal of that period.

http://www.freewebs.com/qualtroughgen/originofthename.htm

Elizabeth