We work at Ogden's Dry Cleaners. We spend most of our day cutting things out of the Reader and doing crossword puzzles. We have been very disturbed by this question for a while. We wanted to know if the elves had the answer. If wool clothing shrinks drastically when it gets wet, then why don't sheep shrink when it rains?
-- Jessica and Caroline, at work
Hey, you two!!! Once the Ogdens read your letter, you'll have even more free time, so you can flip back to the "Jobs" section of the classifieds and see what else the Reader has to offer. And to help you start your new careers with clear heads, here's your answer. First of all, wool doesn't shrink, it "felts." Wool fibers are like human hairs and fish-- covered with a layer of overlapping scales. On the hoof, the wool strands are oily, growing in neat rows, with all scales pointing in the same direction. This keeps the fibers separate and fluffy, even in a rainstorm. But then we come along and buzz-cut the animals; wash, comb, and card the wool; and then spin it into yarn. After all that aggravation, the wool fibers are stripped of lubrication and mixed up, some pointing one way, some pointing another. As the wool strands rub against one another, the up- and down-pointing scales lock together. At the manufacturing stage, this helps make a strong wool fiber. But heat and water lift the scales on the wool strand, and agitation increases the interlocking, which is why you risk turning your new lamb's wool sweater into cardboard if you wash it in a machine. This is felting. The fiber doesn't get smaller or shorter; you don�t magically lose a yard or two down the drain. It just tangles into a stiff mass. But don't despair. Genetics to the rescue. The Aussies are breeding sheep that naturally produce low-felting wool. Then you, me, the sheep, the Ogdens, we're all happy.