any were
burned by the intense heat. Dwellings and other structures were half
damaged by blast.

"Outside a radius of 4 kilometers and within a radius of 8 kilometers
living creatures were injured by materials blown about by the blast;
the majority were only superficially wounded. Houses were only half or
partially damaged."

The British Mission to Japan interpreted their observations of the
destruction of buildings to apply to similar construction of their own
as follows:

A similar bomb exploding in a similar fashion would produce the
following effects on normal British houses:

Up to 1,000 yards from X it would cause complete collapse.

Up to 1 mile from X it would damage the houses beyond repair.

Up to 1.5 miles from X it would render them uninhabitable without
extensive repair, particularly to roof timbers.

Up to 2.5 miles from X it would render them uninhabitable until
first-aid repairs had been carried out.

The fire damage in both cities was tremendous, but was more complete in
Hiroshima than in Nagasaki. The effect of the fires was to change
profoundly the appearance of the city and to leave the central part
bare, except for some reinforced concrete and steel frames and objects
such as safes, chimney stacks, and pieces of twisted sheet metal. The
fire damage resulted more from the properties of the cities themselves
than from those of the bombs.

The conflagration in Hiroshima caused high winds to spring up as air
was drawn in toward the center of the burning area, creating a "fire
storm". The wind velocity in the city had been less than 5 miles per
hour before the bombing, but the fire-wind attained a velocity of 30-40
miles per hour. These great winds restricted the perimeter of the fire
but greatly added to the damage of the conflagration within the
perimeter and caused the deaths of many persons who might otherwise
have escaped. In Nagasaki, very severe damage was caused by fires, but
no extensive "fire storm" engulfed the city. In both cities, some of
the fires close to X were no doubt started by the ignition of highly
combustible material such as paper, straw, and dry cloth, upon the
instantaneous radiation of heat from the nuclear explosion. The
presence of large amounts of unburnt combustible materials near X,
however, indicated that even though the heat of the blast was very
intense, its duration was insufficient to raise the temperature of many
materials to the kindling point ex