I also see a lot of sources that list Tuba or Auzabeth. below are some "interesting" notes on Ephraim, although it doesn't talk about his middle initial. The info is from a document on the history of Grafton. My line is from Levi G. to his daughter Alice.

Note: Settled in Landaff, NH - farmer
Married: 6 JUL 1831

EPHRAIM THAYER was born in Lisbon in 1806, and came to this town in 1869 and located on road 34. He married Ezuba Quimby, of Franconia, and five of their eight children are now living, of whom Willis lives at Victory, VT., Lydia married Levi Bisbee, and Henry, Hibbard and Levi G. all live in Bath. Ephraim Thayer, now seventy-nine years of age, has never been eighty miles from his native town, has never been inside a railroad car, and since ten years of age has not missed a season's work in the hay-field, and has used the scythe in mowing every year since he was fifteen.
http://www.nh.searchroots.com/documents/grafton/History_Bath...