It’s not exactly an accident that so few people have a clear idea of what’s inside a lava lamp, as manufacturers are notoriously tight-lipped about their top-secret recipes. Having said that, knowing ...

Perhaps it’s the conical shape of the vessel, or the gentle blue glow emitted by the material within, or the way the small flecks of solid drift about as they precipitate out of solution. Either way, ...

• British inventor Edward Craven Walker created the “Astro” Lamp which he presented at a trade show in Brussels in 1965 which caught the eye of entrepreneur Adolph Wertheimer. He and his partner ...