History of lava lamps

Hello, this short article is about history of lava lamps. Everyone who would like to build homemade lava lamp should know I think at least something about history of these lamps.
Lava lamp (sometimes also called Astro lamp) was invented by guy called Edward Craven-Walker and in fact it is even patented invention. Well, then it was not called "lava lamp", but just "display device". Edward Craven-Walker named the device as "Astro lamp". This lamp was for very first time presented at Brussels trade show in year 1965. It was there where guys from USA bought rights to manufacture this lamp in United States under name Lava Lite. There are now many companies who create Lava Lamps, but probably only those form company Mathmos are those really original with the exact original formula from Edward Craven Walker.