Examples from history make everything clear, and furnish the best description of proof in the empirical sciences. This applies with more force to the Art of War than to any other. General Scharnhorst, whose handbook is the best ever written on actual War, pronounces historical examples to be of the first importance, and makes an admirable use of them himself. Had he survived the War in which he fell,(*) the fourth part of his revised treatise on artillery would have given a still greater proof of the observing and enlightened spirit in which he sifted matters of experience.
But such use of historical examples is rarely made by theoretical writers; the way in which they more commonly make use of them is rather calculated to leave the mind unsatisfied, as well as to offend the understanding. We therefore think it important to bring specially into view the use and abuse of historical examples.
Unquestionably the branches of knowledge which lie at the foundation of the Art of War come under the denomination of empirical sciences; for although they are derived in a great measure from the nature of things, still we can only learn this very nature itself for the most part from experience; and besides that, the practical application is modified by so many circumstances that the effects can never be completely learnt from the mere nature of the means.
The effects of gunpowder, that great agent in our military activity, were only learnt by experience, and up to this hour experiments are continually in progress in order to investigate them more fully. That an iron ball to which powder has given a velocity of 1000 feet in a second, smashes every living thing which it touches in its course is intelligible in