Field engineers drill war department technical manual Post engineer shops field manual Corps of Engineers : reference data Military engineering : Defences / Army Council Instruction in military engineering : Military bridging and use of spars / School of military engineering Manuel of elementary field engineering field engineering pamphlet British booby traps / prepared under the direction of The Chief of the Imperial General Staff war department technical manual Engineer maintenance troops war department technical manual Standard stream crossing equipment / prepared under direction of the Chief of Engineers field manual Camouflage / Prepared under direction of the chief of engineers field manual Field fortifications / prepared under direction of the chief of engineers field manual Corps of engineers : field fortifications