"It took me a week to grind these lenses." Gottfried Wilhelm Leibniz leaned sideways to rake his spectacles up off the floor. He had to keep his head upright to prevent his biggest and best wig from sliding off his bald, sweaty scalp. This gave him a crick in the neck, however enabled him to get a charming view of muscular white calves pumping in and out as his patroness stormed down the mid-line of the banquet-table.