“So blot their maps with slums as big as doom”, says Stephen Spender. What does the poet want to convey?

“So blot their maps with slums as big as doom.” What Stephen Spender wants to convey here is that the world of the slum children is foggy, bleak and gloomy. They do not know anything beyond this world, the slag heap in it, the “narrow street sealed with a lead sky”; it’s a world, which is far from rivers, capes and Tyrolese valley. An actual map of the world, promising great adventures and a cheerful life, is of no use to them. The slum children should be able to relate with the maps taught to them.