A book of definition and descriptions of the instruments in this war of speed, -- the tanks, the mechanized troops, motorized infantry, radio, planes. There's a history of tanks, from their inception in the last war, through the development to the present. -- German, Japanese, Russian, Italian. There is an outline of the new U. S. Army, the armored divisions, the motorized infantry, motorized Cavalry, Field Artillery, antiaircraft guns and tanks. The power of coordinated action of modern equipment evidenced in the fall of the low countries and France. Information material for the average reader, explaining shock action made possible by motor speed, strategy tactics, etc. in fuller detail than newspapers and periodicals can do.