I found the same to be true. I also found a Federal photo that shows a group of men around what "appears" to be a "rubber blanket" set up as a small tent shaped structure but I am not sure, and as you said there is the possibilty it could also be a wool blanket. Quality of the photography impedes my search! Would you be able to email a copy of your photo to me? I would be glad to share mine and get your opinion, as well.

Regards.

Rob Swinson
32nd & 45th Miss. (Consolidated) Flag Abstract
RESwinson@aol.com