Elizabeth
Your people are dissenters. The overwhelming majority of
Scottish dissenters were Presbyterians who belonged to the Associate, Burgher, Relief or United Secession Churches. The Free Church did not exist until 1843 and many of the older churches united in 1847 to form the United Presbyterian Church.
As it happens, there is a marriage proclamation entry in the parish of Old Kirkpatrick (Dunbarton or possibly Stirling, the parish is right on the border) in 1815 for the couple you mention. There are various references to the family of a James Horsburgh in the same parish and this family has all of the characteristics of a dissenting family, just like your own. Marion Horsburgh may well have been the sister of this James.
James Horsburgh is very likely to be connected to my family as he should be the son of William Horsburgh and Jean Brash. Was James Wyber or any of his children papermakers or involved with paper mills (where lots of labourers were employed in addition to the skilled papermakers)?
If you are interested in understanding about dissenters and how they appeared in the OPR record, you will need to refer to my paper that is contained in the conference notes of the 2nd Australasian Scottish Genealogy Conference (held in Melbourne, Australia, in 2006). Copies of the notes can be purchased via the Genealogical Society of Victoria website:
www.gsv.org.au.
Do you have any extracts from OPRs for this family (including the marriage)? There may be internal clues in whatever you have been able to find to indicate which of the dissenting churches your family belonged to. You may also find this information from marriage certificates from 1855 onwards, but there is no guarantee.
Regards
Malcolm G. Horsburgh