Sometimes my interests coincide.
I found myself in Dartford a few weeks ago, and found a really nice one-room museum attached to its fine Victorian public library. One of its exhibits was part of an old shop, with a rail-cartridge system attributed to the Lamson company.
I knew Lamson for its vacuum systems, one of which we still used when I was at Allders in Bromley in the 1980s. These also occurred in a military context: the second photo below is of a postwar version at the excellent Cornwall At War museum at Davidstow, which I visited just last month.
A quick Google tells me that Lamson indeed manufactured both systems.
