The article below is copied from my brother Jim’s blog https://daytonfamilyhistory.com/. The content should be of interest to many, so I wanted to share it for those who had not yet read it.
When he was a young man in his 30’s, Dr. Wilber Thomas Dayton Jr ran across a letter from Abraham Lincoln in his grandmother’s trunk. His grandma, Anna Flansburg White Dingman, was the daughter of Rev. William Flansburg, a Wesleyan Methodist clergyman who began his ministry in 1849. His newly formed denomination had split from the Methodist Episcopal Church over the issue of slavery. Flansburg’s new denomination was abolitionist.
Much to Dr. Dayton’s delight, the letter was addressed to Rev. Flansburg, his great grandfather.
In it, President Lincoln stated, “you keep preaching it from the pulpit and I’ll preach it from the White House.”
Imagine the historical significance of such a document.
Wilber told me that he never saw the letter again. He did not know whatever happened to the trunk. I have pursued the case, but the relatives who would know anything about it have died.
Does anyone have any knowledge of this letter?
Our search for the letter led us to only one possibility (although it was a long shot)—our grandmother’s old trunk that had found its way to our uncle’s attic. His house had been passed to his son, who is still living there.
A few years ago, we contacted our cousin in Corinth NY, inquiring about grandma’s trunk. Our cousin remembers that many years ago he saw a few old books in the trunk, but now the trunk is empty. We imagine that the letter may have been placed in one of those books, for “safe keeping.”
Dayton Ancestry 
Steve, What a terrific part of history and what a shame that the letter has been lost. However, this demonstrates the need and for those of us that understand, our determination to preserve, expand, and foster our families history. Both you and Jim can only be thanked so much for all of what you have done and do. Terry
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