This undated, unused postcard, which was made in Japan, is simply labeled "Yarn-reeling." I'm guessing that it's silk yarn that is being meticulously separated and spun. It looks like she is holding silk cocoons in her left hand, and that basket could be filled with water and additional cocoons. I suspect that the wide circumference of the wheel is to help with the drying of the spun silk, but I'm really out of my league on this topic, so that's just a guess.
Any reader thoughts on this yarn machine would be appreciated.
It looks like a quiet and peaceful process, but I also suspect one's back and legs would ache after a while.
For a general history of silk, Wikipedia is as good of a place to start as anywhere. I also found a good website, www.silk-road.com, which contains a history of silk processing and this sentence: "A roomful of munching worms sounds like heavy rain falling on the roof."