I just talked with a Mr. Glassburn (86 years young) that owns Glassburn Pottery on Rte. 550 (old U.S. 35) in Chillicothe, Ohio. He is a descendant of David Glassburn. He has a book about the Glassburn family that was published in the early 60's. It is fully researched and most of the work was done by a Glassburn descendant from California, who had degrees from Radcliff College. He has recollection of many of the Glassburns and anecdotes about Glassburns before his time. The book is a treasure trove of Glassburn and other families' info.
Mr. Glassburn works at the pottery/antique/curio store daily from 9 - 5.
I stopped in his store because I was researching Shope and Mustain families from Scioto, Lawrence and Jackson counties. Thomas Shope, my great-grandfather, married Sarah Glassburn who was the daughter of George Washington Glassburn.