Where did craven walker get his idea for the lava lamp?

Craven Walker conceived the idea for the lava lamp while observing a homemade egg timer he saw in a pub. The timer featured a bubbling liquid, which sparked his imagination about creating a decorative lamp that showcased a similar mesmerizing effect. He aimed to blend functionality with artistic design, ultimately leading to the creation of the now-iconic lava lamp in the late 1960s.