It also mentioned a "haversack." That's one of those terms where I'm feeling like I should have heard that before, but don't recall it at all. Apparently it's one of those over the shoulder bags made out of "heavy cotton muslin."
"Size was one foot square with one or three closure buttons. The strap is about 1½” wide and long enough to let the haversack rest on your left hip."
Hmm, I feel a tutorial coming on. I'll have to research a bit more, though.
According to http://www.wisegeek.com/what-is-a-haversack.htm, "At one point, haversacks were standard issue for many militaries. Soldiers carried a small amount of food in their haversacks, along with other vitally important supplies. Over time, haversacks were replaced by rucksacks and later backpacks."