This is a compilation on the subject of trench warfare fortifications as taught by three national Armies - French, German and American. It is intended to be a companion volume to British Trench Tactics, 1917-1918 and is designed to give the enthusiast and scholar some idea of field engineering tasks on the Western Front during the Great War. The contents show the often similar but sometimes unique approaches to the art of trench warfare by the various armies. The book is made up of three parts, each part page-numbered separately, and there are hundreds of diagrams/drawings depicting trenches, earthworks, gun emplacements, MG posts, bomb-proof and other shelters, barbed wire entanglements along with detailed instructions on how to build them or prepare them.Part I: Notes on Field Fortifications (French Army). 274pp. Part II: The Construction of Field Positions (Stellungsbau). 67pp. This is taken from the German publication "Manual Of Position Warfare For All Arms" and was issued by the Prussian War Ministry in 1916, classified SECRET and endorsed "NOT TO BE TAKEN INTO THE FRONT LINE"It was translated from the German and issued by the (British) General Staff in May 1917.(Evidently someone did take it into the front line )Part III: NOTES ON THE CONSTRUCTION AND EQUIPMENT OF TRENCHES, APRIL 1917. 102pp plus five plates of diagramsThis was issued by the War Department, Washington and circulated under a covering letter dated May 16, 1917.Part III: Notes on the Construction and Equipment of Trenches April 1917