At the central station, Marlow sees a painting, "a woman, draped and blindfolded, carrying a lighted torch. The background was sombre—almost black. The movement of the woman was stately, and the effect of the torchlight on the face was sinister" (1.57).
What's up with this? Well, Kurtz painted it, for one. And then there's the whole issue of the woman, and we already know that Marlow seems to sequester women into idealized roles outside the realm of gloomy reality. This woman is so separate that she's a painting, and she's so impossibly idealistic that she, um, isn't real.
On to the blindfolded, torch-carrying part—sounds a lot like justice, doesn't it? Maybe. Some people think this image is about blind Europe trying to bring light to Africa, which would fit in with Kurtz's whole grand imperialist theme. One thing we're sure of: carrying a torch while blindfolded sounds like a real fire hazard.
Which, come to think of it, might just be Conrad's point.