The drum is mounted on gimbals and a motor moves the balls on its
surface around, making a noise a bit like the seashore.
I put on an exhibition, including
this ball machine, at my college in Cambridge, and one of the local aristocracy decided
she wanted to buy it. The original was rather unreliable, like most of my early
contraptions, so I decided to make her a new and improved version. I delivered this
to her estate but it was even more unreliable than the first version.
Although she was very gracious about it all, I decided I didn't really want to spend my
life making things for the rich and famous.