The imagery used in the first paragraph of Chapter XII constantly reiterates the order and cleanliness of France.
He says the entire thing is a garden that must be brushed, watered and trimmed daily, indicating it is very neat and clean. The hedges are "shaped" and symmetrical. The trees are in long, straight rows. The landscape is so orderly Twain compares it to a checkerboard.
The effect of this imagery is to show the reader the beauty and cleanliness of France, which is astounding to Twain.
