These letters appeared in the 1908 Proceedings of the Pocumtuck Valley Memorial Association, in Deerfield, Massachusetts. Dexter Marsh's younger son, George, was living in Colorado when his mother, Eunice, died in 1906. When he returned to Greenfield in 1907, he donated what remained of his father's papers, a few items he had made, and written testaments to his character by prominent men who knew and admired him. The original letters no longer exist, but fortunately were printed in the Proceedings, which is the source of most of the little information that exists about Dexter Marsh's life.
The first letter is from Professor Charles Upham Shepard of Yale, introducing Marsh to Charles Cramer, an American businessman living in St. Petersburg, Russia. The second letter is from Dexter Marsh himself, explaining that he wants help conveying a gift of fossil footprints to Czar Nicholas. From the commentary following the letters, we learn that after two years of effort, the mission proved futile and Marsh had the fossils returned—ignoring the American minister to St. Petersburg's hint that they be dumped into the Baltic Sea.