Do you have a Lava Lamp®? If not, you've probably seen one at a friend's house or on television or in a movie. There's just something mesmerizing about watching those globs float around in that colored liquid!
United States entrepreneurs Adolph Wertheimer and William M. Rubinstein brought Craven-Walker's creation to the U.S. several years later. Their Lava Manufacturing Corporation in Chicago began to make liquid motion lamps and they soon became quite popular.
Wertheimer sold his shares of the company to Hy Spector, who further developed the product and called it the Lave Lite®. Although the company has since changed names and owners several times, it still produces almost all of the liquid motion lamps sold in the United States.
In the 1960s and 1970s, lava lamps were popular with youth and those who identified with counterculture movements, such as the hippies. Today, they're still a popular item with youth and can be seen in many dorm rooms on college campuses around the country.
The “lava" that floats in liquid motion lamps and gives them their unique name isn't really lava at all, of course. It's actually a special type of wax! It sure does look like lava, though, doesn't it?
Liquid motion lamps work on very basic scientific principles. When you add special wax to colored water inside of a lamp that is heated by a light bulb, the wax will warm and expand. Eventually, it becomes a liquid less dense than the water above it.
When this happens, the wax stretches and rises, breaking into smaller globs along the way. When it gets to the top of the lamp, it begins to cool again, since it's farther away from the heat source (the light bulb). As it cools, it sinks to the bottom again and the process repeats.
Although the science behind liquid motion lamps is simple, making them is not. The wax and the water are made up of special secret ingredients that ensure that the specific gravity of the wax and the water are individually matched to provide the best effect possible.