There’s a lot of argument about the importance of spinning improvements in a medieval economy, but there is no argument that the device called a ‘spinning jenny’ helped to start the industrial revolution.
Spinning in general consists in taking individual fibers of cotton or wool or hemp or nettle and twisting them together into a thicker and longer thread. Longer means hundreds of feet longer. As a beginning spinner, I could routinely twist wool threads that were about 4 inches long individually, into a piece of yarn that was 200 feet long. Others could and can do much more.
The spinning jenny was a device that allowed one person to, initially, spin eight individual threads for just one wheel. The wheels I’ve seen pictured had hand cranks on them which the operator turned causing eight separate threads to run up onto bobbins. The original thread spun this way was considered soft and weak, and it was used for weft, the cross threads of a weaving project. The warp threads which run the length of a piece of weaving are under a great deal of tension so they must be strong.
What fascinates me about this description of the first spinning jenny is that of course the thread is thinner and weaker! Force equals mass times acceleration. If a single person is cranking that wheel but eight threads are coming out they can’t be given as much twist and tension as one single thread. However, this changed swiftly when the wheel was driven by water power instead of a person. Jennies then could run many more threads and produce a much higher quality product because much more force was available. I haven’t found a picture of the original eight thread jenny … yet.
This then became a part of the industrial revolution with weaving looms being supplied by spinning jennies so that much more material could be produced with the same amount of human labor. In all the descriptions I’ve read so far no-one is explaining how the fiber was prepared so I can guarantee that there wasn’t an eight-fold increase in production for a single person (since there would be more prep work for someone) but there would be a very concrete improvement, and with water power to drive the wheels the increase in production, both quality and quantity would be serious and real.
I’m going to add pictures when I find some good ones.
I’m also working on a guest post from Catholic scientists, Doctor Lucy Hancock about dust in the atmosphere. It should be up in a few days!
3 thoughts on “Spinning wheels in the 1700’s”
2nd try ok?
What an interesting question. I also do not understand exactly how a thread is so much stronger than a fiber. It is probably something terrible about resistance to torque being different from resistance to extension. Maybe somehow the twisted fibers are an arrangement by which whatever resistance fiber has (to extension longways, to stretching, to twisting, to crushing, to expanding) – whatever resistance it has, is brought into play to resist change when the fibers are made into this twisted arrangement…. . simply achieved but a deep result… could it be like that? I like the image that if someone takes three or four weak threads and they wind around each other then there is something strong.
I’m pretty sure it is friction that increases the strength of two strands or three or five or twenty. As you twist the fibers I think you also increase the surface area that touches. I’d love to see an experiment that tried three strands held together vs three strands that were twisted…