text:  Now, here's Bill Hamilton of the DuPont Company. Are you old enough to remember ironing days when the irons had to be heated on the kitchen stove? On Tuesday morning, usually, out came the irons, at least two of them, or even half a dozen. First, they had to be cleaned. Then they were heated on the stove and laboriously lifted on and off dozens of times. And all the while the ironing went on, they had to be rubbed with a piece of paraffin tied in a scorched rag.