The thrum is actually the little piece of unspun fleece or roving…and as you can tell from the photos it is very cozy and warm. You can see the thrums in the inside of hat knit by Kitty, and then the chevon look on the outside..
Roisin sent these photos along, saying she thought the knitting style–“thrumming” had started in Newfoundland. So, I thought, I will ask my pal knit expert Nigel from Newfoundland–and of course, he knew. Here is what he wrote: “The word is thrum. It is a technique for making warm mittens by working small pieces of fleece into the mitten. They show up as small stitches on the outside but inside they make a fluffy lining. The Yarn Harlot has written an FAQ about them (and her husband is a Newfoundlander). Here’s a link: http://www.yarnharlot.ca/blog/thrumfaq.html7 ” Thanks Nigel!
And here are the matching mitts with the hat..