Here is some new input for this subject. I just got the book "Lead Belly no stranger to the bleus" from Harry Lewman Muisc. It has tablature and lyrics for about 20 of Leadbelly's songs.They give the tuning as a fourth below standard. That is BEADGF#B.
It also has the measurements of his the strings on his last guitar. They are going from treble to base:
.014, .014; .019, .019; .022, .022; .038, .019; .048, .019; .070, .014
I have separated the courses by semicolons and withing a course the pair of strings are separated by commas. The second string is the octave string where there is one.
Note the lowest octave string is thinner than the ones before it. That is because it is tuned two octaves higher.
These measurements are by Bruce Taylor. I don't know if he is the lutier who makes Taylor Guitars.
Murray