The only part of that to which I would add was that "sealed" coffins were not required. I know of a case where the soldier died in a field hospital and his family travelled 60 miles by wagon (which must have been at least two days each way) and packed the body in a wooden coffin in charcoal (I have no idea how they processed the charcoal but it would have had to be in very small particles) and returned it for burial in the family cemetery.

In the book, "Lonesome Dove", a body is packed that way and dragged behind a horse. I read in a biography of one of the people the book was based upon that part of the story was likely true.