Chapter XVI. The Slaver and the Missionary in the Congo River. In the preceding pages some details have been given concerning domestic slavery upon the Congo River. Like polygamy, the system of barbarous and semi-barbarous races, it must be held provisional, but in neither case can we see any chance of present end. Should the Moslem wave of conquest, in a moral as well as a material form, sweep--and I am persuaded that it will sweep--from North Africa across the equator, the effect will be only to establish both these "patriarchal institutions" upon a stronger and a more rational basis. All who believe in "progress" are socially anti-slavers, as we all are politically Republicans. But between the two extremes, between despotism, in which society is regimented like an army, and liberty, where all men are theoretically free and equal, there are infinite shades of solid rule and government which the wisdom of nations adapts to their wants. The medium of constitutional monarchy or hereditary presidentship recommends itself under existing circumstances to the more advanced peoples, and with good reason; we nowhere find a prevalence of those manly virtues, disinterestedness and self-sacrifice to the "respublica," which rendered the endurance of ancient republics possible. Rome could hardly have ruled the world for centuries had her merchants supplied Carthage with improved triremes or furnished the Parthians with the latest style of weapons. We must be wise and virtuous before we can hope to be good republicans, and man in the mass is not yet "homo sapiens;" he is not wise, and certainly he is not virtuous.