In this Ecumenical Thanksgiving service, the Rev Dr. Libby Gibson, pastor of St. Mary's Episcopal Church of Barnstable, will lead the annual ecumenical Thanksgiving service hosted by the Historical Society of Old Yarmouth. The service will be Nov. 18 at 3 p.m. in the Kelley Chapel, off Route 6A, Yarmouth Port. The former Quaker Meetinghouse contains the original pews and a pot-bellied stove. The program will include special music and singing of harvest songs. The public is welcome.