It is not my place to write a dissertation upon the military art; I have only to draw attention to the knowledge of sieges, which form so prominent a part of it. Neither does it come within my plan, or the limits allowed me, to treat of the science of fortification; mine is but to employ “the philosophy which teaches by example,” and exhibit the “Great Sieges of History.” And valuable is the lesson to all,--to the student of the art of war, to the soldier at the cannon’s mouth, to the minister who plans expeditions, and to the people who furnish the means for them. There is scarcely a siege in this volume barren of instruction; the principal of all being, that little can be achieved in these mortal conflicts by either besieged or besiegers, without energy constantly strained to the highest pitch, sleepless watchfulness, keen and anxious observation, consummate prudence, undaunted courage, firmness that is proof against attack or accident, great physical powers of endurance, and MILITARY GENIUS. When armies are opposed upon the wide field of a country, the game of chess may be played out by tacticians, or by great chance, success may be obtained by a dashing _coup de main_; but in important sieges, man is like the stag brought to bay, every faculty is forced into intense action, and the slightest error, the faintest relaxation, may produce irretrievable ruin, with such consequences as no other event presents. In great battles, armies may be annihilated; but in captured cities peoples are immolated and humanity is degraded by the wild indulgence of its most brutal passions. It is more than curious, it is wonderful, to observe how many sieges will be found in this volume, whose fate has been decided by means with which the art of war, as taught in the schools, had nothing to do; and it is always the captain of the greatest genius who seizes upon every unforeseen discovery, any extraordinary accident, any suddenly-perceived natural advantage, to defeat the best-concerted and most scientific plans of his adversary: in one instance the fortune of an assault is changed by suspending a pig over the walls by a string fastened to his leg.