Crosley bought the rights to the Icyball refrigeration idea, and brought it to market. Powel Crosley had a gift for recognizing great ideas and gift for marketing. Crosley built thousands of Icyballs in at least two factories, one in the United States and one in Canada. Icyballs have been spotted throughout North America and as far away as Africa. The Canadian made Icyballs carry a tag indicating that they are Deforest Crosley Icyball, those made in the USA are labeled Crosley Icyball. The Icyball is an intermittent heat absorption type of refrigerator. A water/ammonia mixture is used as the refrigerant . Water and ammonia combine easily. So, they combine in the hot ball at room temperature. When the hot ball is heated, for about 90 minutes, the ammonia evaporates first because it has a lower boiling point than water. The other cylinder is in water to help condense the ammonia in the cold ball. When the balls are fully charged, the cold ball is placed in the insulated box, as the ammonia evaporates to recombine with the water in the hot ball it removes heat, cooling the inside of the refrigerator for 24+ hours. A hole in the cold ball was for a special ice cube tray. If the above isn't completely correct, it's because I really don't know anything about refrigeration, feel free to Email me and correct me. This page is our complete file on the Icyball if you have additional ads or information please let me know.