Wow, how to describe a mangle. The ones we had were operated sitting down. The mangle had a big padded cloth-covered roller and a metal plate that curved to the roller's contours. The item of clothing was placed between the roller and the hot plate and, using knee controls, you caused the roller to press down on the clothing. The roller would turn, and the person operating it would control the direction of the piece of clothing. It was a real art to make the roller go up and down while turning the shirt, for example, without causing any unwanted creases. Here's what they look like:
