Vintage French advertising chromolithograph titled "Manchon Le Trèfle – Éclat pénétrant des rayons X" (circa 1900) created by artist Charles Delaye.
The poster advertises incandescent gas mantles ("Le Trèfle" or The Clover brand) sold by the Société Nationale d'Incandescence in Paris, humorously exaggerating the lamp's intense brightness as an X-ray-like penetrating glow that reveals the skeletons of an admiring couple.