All Labor bikes at this time had this type of frame, not just the very rare monobras (monofork) model. So nothing to do with the special strains induced by doing away with half of the bike..... As Joël points out the Labor badge shows a railway bridge with a train going over (You can see the detail by clicking twice on the picture). The link is
http://www.pianosromantiques.com/
Alexander March Bordeaux France