THOMASTON — The General Henry Knox Museum in Thomaston is accepting registrations for two free professional development programs for history and social studies teachers in July. Funded by Doris Buffett’s Sunshine Lady Foundation and approved for both continuing education and college credits, the programs are offered under the auspices of the museum’s Center for Early American History and scheduled for July 11-15 and 18-22.Inspired by a letter dating from 1794 recently acquired by the museum in which Henry Knox wrote to his daughter Lucy that her correspondence provided “a cordial to [his] spirits,” the summer teacher programs will focus on personal letters and the rich historical source material they provide. The museum’s concurrent summer exhibit will showcase Knox family letters, and visiting professor Dr. Konstantin Dierks of Indiana University, author of “In My Power: Letter Writing and Communications in Early America,” will speak. Also, Dr. Marla Miller of University of Massachusetts at Amherst will discuss her scholarship on women’s industry in the 18th century and her most recent work, “Betsy Ross and the Making of America,” and noted professors and lecturers from Simmons College, San Diego City College, the Gilder Lehrman Institute, the Tate House Museum, and the Maine Historical Society will conduct seminars both in person and online.Field trips to the art museums at Bowdoin and Colby colleges and a ferry trip to Islesboro, where renowned food historian Sandy Oliver will host an open-hearth cooking lesson, round out the programs.Teachers may sign up for either or both weeks. All books and classroom materials are provided free of charge to participants, and housing with museum member families is available as space allows. The two-week program is approved for three credit hours through either the University of Maine Hutchinson Center or Framingham State College, as well as for 4.5 continuing education units, or CEUs. Participants also will receive a $100 cash stipend per week.Contact Sophie Mendoza, Knox Museum education coordinator, at 354-0858 or http://firstname.lastname@example.org for more information about the programs and to request registration materials. Space is limited.