How to Insert Thrums in Your Knitting - step by step pictorial (gonna make thrummed mittens for myself one day!
thrumming tutorial (thrumming is a method of knitting loops of raw wool into a piece, in this case mittens, to add an insulating layer)
Ravelry: Thrummed Mittens pattern by Helene Driesen ~ . Hands stay super warm in thrummed mittens. Perfect over fitted leather gloves for scrapping ice and clearing snow; the leather never gets damp.
Thrummed Mittens - jacket or hat
Ravelry: East Coast Mittens pattern by Lynette Meek
Thrums add warmth, also decrease stretching. So a thrummed item-say, a hat- thrummed fits a newborn; as the baby grows, removing rows of thrums allows the hat to grow as well.