you beat me to it - or https://en.wikipedia.org/wiki/Delay-line_memory https://en.wikipedia.org/wiki/Delay-line_memory in general, space is probably closer to a

you beat me to it - or https://en.wikipedia.org/wiki/Delay-line_memory https://en.wikipedia.org/wiki/Delay-line_memory in general, space is probably closer to an electrical delay line in practice.