Maybe it is sail cloth but that should be water repellent. The boat and boating motifs suggest that, or maybe marine fabric of some kind. I would make outdoor cushions out of it and paint the colors in your color, or use the fabric dyes to paint in the colors. Also, those great quilt patterns for on it to hang outside, or a flag type thing.
Good luck.

canvas is made from cotton...
can be used for many home dec projects, or even for tote bags/shopping bags. holds up well and is fairly easy to work with (unless it's really heavy canvas; then you need a bigger needle)
i love finding things like that at the thrift stores, in the real stores canvas can be quite expensive.

Drapery cottons can be used for a variety of things. I've tied polar fleece to them and made car quilts. I've also made totes, placemats, table runners, trivets, baby changing pads, chair cushions, nap mats, etc. While they might be a little heavy for quilting you can still use them by themselves or with denim or corduroy for tied utility quilts.

I had some 3-5 yards of this Waverly fabric too and it also said 100% cotton! Beautiful fabric & strong..got mine from thrift store for $2. So now i know it's drapery materials?