We were somewhere around Barstow, on the edge of the desert, when the drugs began to take hold. I remember Spehro Pefhany saying something like:
A memory faintly stirs of something I read yonks ago. I think it might be something to do with an old signalling system of the late Victorian/Edwardian period - maybe railway related. The cells were used in banks contained in wooden cases.
I distinctly recall such cells being used in an intercom system in my primary school - it never worked, to the best of my knowledge.