Skip to content

So, one of them calculation things

Vis a vis something I saw this morning.

So, how much human labour would be required to handspin the current global output of machine spun yarn?

Weird question I know. But interesting all the same for a certain level of interest.

I see one modern number which is 40 metres per second of yarn from a modern machine.

I see a re-enactor number (which is probably longer than actual pre-modern wimmins who did this a lot) of one metre a minute.

After much practice since this past spring, I now can spin an arm’s length of highly twisted fine thread, using the long draw, with naturally colored cotton whose fiber length is less than an inch, with my brass Indian takhli support spindle, in less than one minute.

Those are good enough numbers.

At which point I get stuck. Can’t see any numbers for global production of yarn in metres (70 million tonnes for manmade, but that’s not quite the same thing) and 70 billion sq metres of cloth made in India alone a year. But what’s length of yarn to sq m of cloth? Yes, obviously, depends upon the yarn and the cloth. But some rough idea?

The aim is to work backwards. The machines are 2,400 times faster at the spinning than humans alone (although the hand spin is still using a machine we’ll overlook that). So, how many human labour hours do we need to produce the current global production of yarn?

A guess here is that there’s not enough female labour hours among the 7 billion of us to produce that amount. But it would be fun to check that.

Aha. Global yarn (cotton, and cotton alone) production is perhaps 20 million tonnes. Not an accurate number but useful as to magnitude.

Hmm. T-shirts seem to be made from cloth that is 200 grammes per square metre. Ish-ish.

But that’s still not getting to metres of yearn per fabric produced which is what we need for hours of labour…..

OK, and yes, the $3,500 shirt in the comments. 2,000 metres of thread/yarn to 1 sq m of cloth. We have 70 billion sq m of cloth. And so 140 trillion metres of thread. Or, 140 trillion womanminutes of handspinning. Divide by 60 and 2,000 (minutes per hour and hours of a working year) to give us 1166666666 hours. Or, 1,166,666,666 woman years of labour.

Hmm, surprises. It would actually be possible to do this by hand. If one third of all women, of all ages, did nothing but hand spinning we could produce the world’s current consumption of cloth.

Anyone got any different calculations to offer?

17 thoughts on “So, one of them calculation things”

  1. The web article on the $3,500 shirt(*) has the estimate that 5 yards of 1 yard wide cloth are needed for a medieval shirt and that with a fine weave (25 threads per inch) it would need 9,000 yards of thread to make. So to one digit accuracy, about 2,000 metres of thread to 1 sq metre of cloth, and the Indian production of cloth would need 140 billion kilometres of thread, or roughly 1,000 times the Earth Sun distance.

    (*) I’m not linking as links always seems to get classified as spam, Google will find it.

  2. “So, how much human labour would be required to handspin the current global output of machine spun yarn?

    Weird question I know.”

    Its not a weird question at all, sort of thing I think about all the time, which might be why I hold the lefties to be cunt-in-the-brains.

  3. “Hmm, surprises. It would actually be possible to do this by hand. If one third of all women, of all ages, did nothing but hand spinning we could produce the world’s current consumption of cloth.”

    But would all those spinsters have to remain unmarried?

    Hmmmm… Could be a solution to the over-population problem. What do you think? 😉

  4. Reminds me of the Nordhaus study – “The amount of work that it once took to procure one hour of light — cutting down small trees, stripping them of small branches, and so on — now yields 51 years of light.”
    Tom has done this with yarn.

  5. The daily amount of work (physics definition of “work”) of which the average human is capable is about 1 kwh (about 13.5p worth of electricity). So, what is the total kilowattage of the global fabric manufacturing machinery?

  6. Following up from decnine’s point, bear in mind that the whole textile spinning and weaving process started to be challenged by factories in the mid 1700s before Watt’s steam engine was a thing. The early factories were driven by waterwheels, which I believe would only produce a few kiloWatts power to run the whole “manufactory”. You can get 3kW out of a 13A socket in the UK.

    (And I certainly don’t think a human can produce 1kW, since that’s about 1.3 horsepower, but decnine’s general point still stands).

    Aside from specialist stuff like Harris tweed, the whole textile industry has been machine-powered since what, the 1860s? 1870s? Human powered spinning and weaving were just about the first things to be displaced in the industrial revolution.

  7. Dennis, Legend of the Parish

    So, how much human labour would be required to handspin the current global output of machine spun yarn?

    That’s easy: About as much human labour it would take to yank Richard Murphy’s head out of his ass.

    Other than that, I’m thinking Timmy has a bit too much time on his hands today.

  8. I don’t think you can even make the comparison, given that the pre-machinal production of fabric was a complete economy involving a fair number of guilds, each specialised in a single step in production. ( the famous Leiden cloth involved 7 guilds directly, and 12 others involved in all the other things around it…)

    And this wasn’t done as an employment exercise, but to make the production process as efficient as possible to keep up with demand…
    Even then, unless you were nobility with too much money and too little sense, you never bought clothes “for a season”, but rather for years, if not decades when considering overclothes.
    With embroidery not some fun pastime for creative post-hippies, but a necessary skill for both men and women to protect their clothes from excessive wear. ( Elisabethan blackwork is a commonly seen thing in re-enactment land..)

    I don’t buy the $3500 though… There’s still some small-scale production of triple-A grade re-enactment gear, and that stuff (all hand-produced, according to techniques as accurate as possible for the period), while seriously expensive, does not come near that number.
    A pure linen undertunic or undershirt will set you back somewhere between €120 to €160, depending on fabric weight. Then again.. one of those will last you up to a decade with proper care, longer if you count cutting it up for the eventual children.
    So value for money, those things are actually cheaper than the €3 shirts you get from the usual cheapo outlets which barely last a season..

    Somewhere ROI must be taken into account as well.. Something, something Vimes’ Theory of Economy.

  9. Bongo, Tim Harford took a similar example, and calculated (IIRC) that since around 1700, the efficiency of light production has improve by about 500,000%. Today, light is so cheap, it is comparatively more expensive to get up to cross the room to turn it off than to leave it on.

  10. Professional cyclists can maintain an average output of 400W over a period of a few hours, say 2-3kW in a day. To achieve this they ingest 5-8,000 kCals daily.

  11. If you boys would work in joules instead of watts, you could eliminate much confusion.
    I’m interested in the answer, but I’m confused for sure. And I don’t think I was before reading these comments.

  12. “Hmm, surprises. It would actually be possible to do this by hand.”

    Not quite. That’s Indian production, not world production. The Indian population is ~1.2 billion so you’re not going to find 1.167 billion women there. Yes, they produce more cloth per capita than some other countries, but when you add in China and the south east Asian countries’ production your initial thesis is probably correct.

  13. That should have read 2-3kWh in a day (7-11 MJ for 21-34 MJ of food intake, just to keep the Texicans happy).

  14. The aim is to get the drink to something like 12 to 14% alcohol by volume. Somewhere in the sweet spot around white and or red wine. Just because that’s the best manner of getting it absorbed.

    As I was told by the best publican ever that is.

    So, Beefeater is 40%, tonic is 0%, do the math.

Leave a Reply

Your email address will not be published. Required fields are marked *