I saw this database on Ancestry.com and it almost makes me want to upgrade my Ancestry.com back to a World membership: London, England, Clandestine Marriage and Baptism Registers, 1667-1754. I did search it and saw several Percivals, several Maitlands, lots of Oliphants, a few Chinns and no Kirtleys. I love the time frame also.
If you don't have a subscription to Ancestry.com, try this link to read why and where these marriages may have been performed.
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