Often see these lamps on ebay,autojumbles and flea/antique fairs also,nearly allways described as railway lamps,usually the cover that clips over the glass/lens is missing,now after seeing these photos they could possibly be nothing to do with railways but simply a road traffic control lamp used by the military for convoy route marking at night,there is a photo of a pile of these in a jeep,where they might also clip onto a tripod/spike,on the motorcycles they seem to be clipped onto some kind of tray,and were probably left on there and the bike parked up near the kerb.
above,they have a red and green function.
below,cover has direction arrow,plus these markings.
above,you can just about see one on this bike.
Hi Rob, there's at least another three in that side car body, on a verge they must be clipped onto some kind of tripod or spike, on a kerb free standing, suppose we'll never know as not many photos were taken at night.
These lamps may have been used to mark cleared routes through minefields during night advances / attacks. Paraffin lamps were certainly used to mark cleared routes through minefields in the Western Desert during night advances / attacks and I understand that were suspended on poles.