Directions
1. Separate a strand of woolen yarn into fibers. Examine both these fibers and fibers pulled from the raw wool. Would you describe these fibers as coarse or fine?
2. How do the fibers feel to touch?
3. Test the strength of the wool fibers by trying to break them.
4. Measure the length of several fibers.
5. Why was it difficult to straighten the fibers to measure them?
6. Extend the fiber to its full length, then release. How does this prove the fiber to be elastic?
7. Examine the fibers under the microscope. Describe. Notice that the wool fiber is cylindrical in shape. Notice that it is covered with scales which overlap much as do the tiles of a roof or the spines of a pine cone.
8. Hold one pine cone with the spines pointing upward. With the spines of the other pointing downward press the second cone down on the first. What happens? Just so the scales or points of the wool fibers hook into one another and interlock. These scales or serrations give to the wool fiber its chief characteristic which is the power of interlocking known as felting or shrinking.
9. See Textiles, page [2], the drawing of a magnified wool fiber. Make a drawing of a wool fiber.