I have doen extensive research on the Tannahill's/Tannehill's. Actually, It's Thomas Tannahill, born 1580. There are 2 lines---the Fenwick line and the Paisley line---I have the research on the Paisley line. My report is at 64 pages as of today. You can e-mail me at jdlkht@aol if you would like more info.
Jean Tannahill