This is from page 17 in the green book; it's a bit short of half way through Part 1:
"Once I remember, we came upon a man-of-war anchored off the coast. There wasn't even a shed there and she was shelling the bush. It appears the Freanch had one of their wars going on thereabouts. Her ensign drooped limp like a rag, the muzzles of her long six-inch guns stuck out all over the low hull, the greasy, slimy swell swung her up lazily and let her down, swaying her thin masts. In the empty immenisty of earth, sky, and water, there she was, incomprehensible, firing into a continent. Pop, would go one of the six-inch guns; a small flame would dart and vanish, a little white smoke would disappear, a tiny projectile would give a feeble screech--and nothing happened. Nothing could happen. There was a touch of insanity in the proceeding, a sense of lugubrious drollery in the sight; and it was not dissipated by somebody on board assuring me earnestly there was a camp of natives--he called them, enemies--hidden out of sight somewhere."