Actually the weasel referred to in the song is a device used with a spinning wheel to wind up the yarn produced and it would make a pop sound when a length equal to a skein had been produced.
https://upload.wikimedia.org/wikipedia/commons/thumb/2/24/Noe_haspel.jpg/220px-Noe_haspel.jpg
https://en.wikipedia.org/wiki/Spinner%27s_weasel
Actually the weasel referred to in the song is a device used with a spinning wheel to wind up the yarn produced and it would make a pop sound when a length equal to a skein had been produced.
https://upload.wikimedia.org/wikipedia/commons/thumb/2/24/Noe_haspel.jpg/220px-Noe_haspel.jpg
https://en.wikipedia.org/wiki/Spinner%27s_weasel