daf bit: Shabbat 99

The list of labors forbidden on Shabbat is derived from those required to build the mishkan (tabernacle). Today's (and yesterday's) daf talks about some of the construction details of the mishkan. The torah describes two types of curtains; the lower curtains were made of blue wool, purple wool, crimson thread, and fine linen, and the upper ones were of goats' hair. The g'mara says the upper involved greater wisdom, because of the lower it is said "and all the women that were wise-hearted did spin with their hands", while of the upper it says "and all the women whose heart stirred them up in wisdom spun the goats. It was taught in the name of R. Nechemiah: it was washed and spun directly on the goats. (99a)

I am not aware of a technique by which that would be possible, but I am not wise in the ways of spinning.