I'm not a huge fan of supported spinning, but I'm quite enjoying the technique when I get to do it. One of the things I remember wondering about when I first saw it was the use of a temporary cop - winding on the spun yarn near the tip of the spindle. It seemed weird to me to do that, as it means you have to wind off the temporary cop again and then wind on properly to the permanent cop.

This was one of the things that started to make sense a few years later, when I tried it with significantly more practice in spinning, and with more appreciation for spinning efficiency. Yes, you do wind your yarn twice with that technique - but it doesn't matter if the temporary cop is rather sloppy, so you can wind on very quickly (by twirling the spindle) and go on spinning. It also means that if you tend to add uneven amounts of twist in your makes, winding off and on again gives the twist a chance to partly redistribute and even out. One of the main pros for me, though, is the fact that winding to the temporary cop is less of a disruption in the process than winding to the permanent cop. I can wind much easier and better to the permanent cop if I take the spindle out of its bowl and place it on my leg or hold it in my hand, depending on the position of the rest of me and the spindle. Doing that is a major movement as compared to the small movements done during the spinning process. Add to that the fact that a typical make in supported spinning is much shorter than one in distaff spinning or long suspended spinning, where the winding process is already the main disruptor of the process, and it becomes quite clear that going from "spin position" to "winding position" is better done less often.

Not all variations of supported spinning use the temporary cop, though, and that is another thing I find fascinating with this type of spinning: There's a plethora of subvariations and possibilities. Like you can do a short draft as for worsted spinning, while the spindle twirls much like when you spin long suspended. This brings with it with the same necessity of having a feeling for when the spindle will stop, and twirling it again before it has come to rest completely. You can also do a kind of longdraft technique, either in the park-and-draft variation (which is easier) or in continuous spinning, and with the latter either drafting against the spindle weight, if your fibre is slippery enough to allow it, or helping with the hand close to the spindle by gripping the thread above the spindle.

If we're looking at evidence in medieval sources, supported spinning seems to be the exception, not the rule. Just like spinning with top-whorl spindles, there is a little bit of evidence for it, but not much. I know of one single picture showing a woman spinning with a spinning bowl; unfortunately, I've not made a proper note of where it is, and a quick internet search turned up the picture (yay!) but also no reference to where it's from (gnah).

I've done better with remembering the source of the image with a top-whorl spindle: it's in an English manuscript in the British Library, and it shows the Bearded Woman of Limerick spinning with distaff and top-whorl spindle. That's very nicely matching the fact that there are a few hooked metal spindles in the National Museum in Dublin that are very suitable for use as top-whorl spindles, possibly without an extra whorl in some cases.