There has been a popular fascination with X-rays ever since their discovery by Wilhelm Conrad Röntgen. And this fascination shows no signs of abating. Much of the material that is of interest for the historian of radiology is transient. The term "ephemera" covers a large range of material including leaflets, trade cards and tickets. This type of material has not traditionally been kept by libraries and not been collected in any systematic war. The material illustrates social history and popular views in a war that the more durable material cannot and is an evocative reminder of the past.