Ok, spent some time with the tote of fabric and lighter doing burn tests and have separated it into quilting cottons (on the chair seat), blends and not suitable for quilting yardage in the tote, and the large bag seems to be an actual stash from 1950-70s scraps. Finding the butterfly fabric was quite the surprise -- mostly I saw the red/white because that is most of it. I haven't measured it yet, not sure it is big enough for a full twin back, but plenty big for a throw.
I will take all the non-suitable/blends to my sewing group for "right of first refusal". There is an awesome cotton that would be great for bags but not the right weight for quilting and some other good stuff. Some of the Springs fabrics were indeed blends, but usable blends maybe 80% cotton, and large enough for crib-throw backs.
I will also take the bag of vintage bits and sort it out... I collected vintage fabrics for years meaning to sell them on ebay but I never did and then my eBay user name (FabStasher!) got stolen and used for bad stuff. Anyway, sold off a couple hundred yards before I moved. I don't want to deal with the little bits but I will see if anyone in my current guild is into the vintage pieces.
No separate pictures yet but there were also two dragon hoard suitable fabrics in there! One is a glittery dark red, I've washed it once and the glitter did not fall off (hooray!) but quite a bit of color came off. Then I found a darker burgundy piece with some gold embellishment, and there is a small load of reds in a hot wash as I type.