I've just completed reading a 1984 copy of Elizabeth Zimmermann's Knitter's Almanac. If you haven't read it yourself, it's a friendly and charming way to visit with the late great expert knitter. Many of my knitting friends have owned several copies. They get so well used. Elizabeth was a passionate knitter who knit all year, day in and day out. Creative and artistic she was also a genius. Who would have thought to design a knit shawl based on PI? Elizabeth did. She claimed the shawl was based on the "...mysterious relationship of the circumference of a circle to its radius. A circle will double its circumference in infinitely themselves-doubling distances, or, in knitters' terms, the distance between the increase-rounds, in which you double the number of stitches, goes 3, 6, 12, 24 and so on." You don't need to be a genius to understand this book. It's a charming book full of practical hints and tips. You will like Elizabeth and if you're passionate about knitting you'll become even more so.