burning city. Ultimately it was estimated that 76,327 buildings were completely destroyed, and 70,147 partially destroyed, or nearly 92% of all the structures in the city of Hiroshima. A census taken five years later indicated that some 200,000 men, women and children may have been killed from the one bomb. (64, p. 4) NAGASAKT On the morning of August 9, 1945, the B-29 "Bock'’s Car" lifted off the Tinian airstrip and headed for Japan to drop the second atomic bomb, this one using plutonium. The primary target for this drop was Kokura, but poor visibility forced the plane to head for its secondary target, Nagasaki. At exactly 10:58 a.m. local time, the bomb fell away and later the parachute opened. The A-bomb which floated donward from the heavens on its parachute over Nagasaki was called the "Fat Man", because of its egg-like shape. It contained approximately 30 pounds of plutonium. The firing mechanism was unlike that of the "Little Boy". based on a new concept called "implosion". Normally in an explosion the force of the blast is directed outward. the force is directed into a point. It was In implosion, In this bomb, however, there was a shaped charge which surrounded a hallow sphere of plutonium, like the meat surrounding the seed of a mango. As long 46 (co“