In the natural history of the world we discover that certain tribes of sentient beings prey upon certain other tribes; and this seems, on a cursory view, to be very shocking to the finer sensibilities of our nature; yet it is an arrangement which results in a larger amount of sentient enjoyment than could otherwise obtain among these lower denizens of our inexplicable world. The most vigorous--that which embodies within itself the greatest and the most various elements of vitality and power--the most vigorous, I say, prevails; and if the negro race of our continent should begin to wane and finally go as the 'poor Indian' has done--a fate which I do not here predict for him--the field thus vacated will not be lost, but occupied at once, and in time to its fullest extent, by a race of greater capabilities for culture, progress, and enjoyment. The physical world has attained to its present advanced geological condition through much of violence and pain; the same is true in a moral sense of mankind at large; and there may be still quite a great deal of this same career to run. Sympathy of itself is blind, and may 'kill with kindness.' It has often done so. But it is a noble emotion: let it play its role, since, in the working out of destiny, 'the will may be taken for the deed,' and a good accomplished which was not intended or foreseen. Governments may not be greatly at fault for not proposing 'high moral aims.' We need only recall the names of Watt, Fulton, Stevenson, Morse, and others of that class, to perceive that great moral changes are brought about when no moral purpose is intended. It is not affirmed that these benefactors of mankind never thought of the moral consequences which their purely physical labors would produce, but only that the moral consequences were not the incentive to the mechanical achievement. The genius of invention had to work out its legitimate results through the innate force of its own peculiar constitution. The impetus was that of essential genius, not of moral calculation. The same thing is true of the cultivation of science for its own sake. The stargazer with his telescope, the chemist with crucible and retort, the physiologist with his chemical and optical aids, the purely scientific thinker--all who prosecute science for the love of it--have wrought out results which are breaking as light of the clear morning sun upon the history of nations, thus enabling us to avail ourselves of the past in order to comprehend the status of the present and the possibilities of the future.