countermeasures are taken. In areas where earthquakes are common, a countermeasure known as "Drop, Cover, and Hold On!" is practiced. Likewise, in tornado-prone areas of the United States, especially those within Tornado Alley, tornado drills involve teaching children to move closer to the floor and to cover the backs of their heads to prevent injury from flying debris. Some US states also practice annual emergency tornado drills. History The dangers of viewing explosions behind window glass were known of before the Atomic Age began, being a common source of injury and death from large chemical explosions. The Halifax Explosion of 1917, an ammunition ship exploding with the energy of roughly 2.9 kilotons of TNT, injured the eyes and faces of hundreds of people who stayed behind and looked out of their windows after seeing a bright flash, with 200 blinded by broken glass when the slower moving blast arrived. Every window in the city of Halifax, Nova Scotia, was shattered in this catastrophe of human error. In the Record of the "Nagasaki A-bomb War Disaster", those close to the hypocenter (Matsuyama township), were described as all having been killed, with the exception of "a child who was in an air-raid shelter." A little further away, Professor Seiki of Nagasaki Medical School Hospital was building an air-raid dugout 400 m from the hypocenter of the detonation and survived. Chimoto-san, who was atop a distant hill that creates the valley in which Nagasaki is located, performed the similar "hit the deck" maneuver upon seeing the bomb drop, which was notably prior to the detonation. However despite having these few seconds of relatively unique warning, he did not stay on the ground for long enough after the flash subsided, and received some translational injuries due to prematurely standing-up again, at which point the slower moving blast wave swept past him and carried him with it for a few meters. According to the 1946 book Hiroshima and other books which cover both bombings, in the days between the atomic bombings of Hiroshima and Nagasaki, some survivors of the first bombing went to Nagasaki and taught others about ducking after the atomic flash and informed them about the particularly dangerous threat of imploding window glass. As a result of this and other factors, far fewer died in the initial blast at Nagasaki as compared to those who were not taught to duck and cover. The