The author wishes to point out that in a volume, such as this, which deals largely with modern war strategy, not a little of the information which has been placed at his disposal by official sources is not, at this time, available for publication. For this reason, the tactics herein presented deal mainly with the larger issues, but it is believed that a sufficient description of the principles has been given to make clear the chief wonders of modern land war. For the same reason, the author has not entered upon controversy with regard to the origin or the character of the Great War, but has stated only such facts as are admitted both by the Allies and by the Central Powers. Military reasons preclude the naming of those officers and officials who have been especially courteous in giving information and advice, but it may justly be said that counsel and assistance has been received from American, French, Belgian, and English sources. Acknowledgment is made herein of the courtesy of _L'Illustration_, _J'ai Vu_, _Le Monde Illustré_, _Panorama de la Guerre_, _La Grande Guerre_, and _Le Miroir_ of Paris; of _Illustrated London News_, _Graphic_, _Sketch_, _Sphere_, _The War of the Nations_, and _The War Illustrated_ of London; for the use of illustrations taken from their publications and being from photographs or sketches made by their photographers or artists in the field. For the use of official photographs taken by the Photographic Corps of the armies of France, Belgium, and England, acknowledgment of courtesy also is made. PREFACE Never, in the history of the world, has the courage of the individual soldier and the skill of the individual officer been so superbly witnessed as in the Great War. Still less has it ever been that a general dealt with such mighty forces or was confronted with such appalling problems of organization. The brain would reel with its immensity were it not for the fact that the brain grows accustomed to prodigies, to prodigies of valor, of skill, and of self-sacrifice. Two great questions stand out paramount in the Great War. It is a conflict of principles, it is also a conflict of strategies. These two are interlocked. The strategy that dooms hundreds of thousands to death recklessly is the result of one principle; the strategy that makes every soldier a hero and a patriot is based on an opposing principle. These are hereinafter set forth and tell their own hideous and their own glorious tale. War, such as the Great War, has never been before. The changed conditions did not come suddenly, they came gradually, and each new death-dealing device was brought about as the result of some disaster that had gone before. The Siege-Gun explains the fall of Liége, the weakness of fortifications explains trench warfare, the defense at Ypres explains the poison gas, and the trench deadlock foreshadows the tank.