Dry cleaning is a process which removes dirt and stains from garments using a solvent other than water. As a profession, dry cleaning dates back to Mycenean civilization, around 1600 b.c. Archaeologists surmise that these ancient dry cleaners used absorbent earth or powdered meal to draw sweat, odors, and soil from clothing. Later innovations depended more on liquid solvents than on absorbent powders. In the seventeenth century, for instance, one adviser noted that turpentine would remove rosin by evaporating stains from the weave. Since the eighteenth century, people have protected fabrics from shrinkage and warpage by replacing water-based cleaners with chemical substitutes such as naphtha, benzine, and benzol. One technique involved the vigorous application of grated potatoes as a means of cleaning unwashable materials, furniture, and even oil paintings. Other products, such as pinene and camphene, successfully removed spots. A common home dry cleaning method called...