I know that the navies of the period wore clothing, mainly pants, made of sailcloth (Canvas). We also know that they made dusters from canvas and rain slickers from painted canvas. We also know that they made shoes out of canvas. So it would seem that Canvas, although not as durable as wool and jeans, may have had more uses as clothing than we suspect.

But I am not sure that this is what the article is talking about. Chuck's reference to Onasburg is good also. But Onasburg is not durable enough for uniforms.

It seem pretty clear here in this article that they had something else in mind to wear as "Summer uniforms" other than wool. And the south wasn't widely know for their large "sheep plantations". Althought they had to have gotten their wool from somewhere.

Another thing is January isn't the time of year that one would expect there to be a large amount of cotton available for making of Onasburg and Canvas, as they would have been depending on the last years crop for materials. And I would think it would be too early to be shearing sheep of their winter coats. So this seems to be at odds with conventional thinking.