In his letter, Adams stated that the bat was the "lowest form of animal life", and that, until now, "reasons for its creation have remained unexplained".

In one incident, the Carlsbad Army Airfield Auxiliary Air Base … near Carlsbad, New Mexico, was set on fire on May 15, 1943, when armed bats were accidentally released.

Bat bombs were an experimental World War II weapon developed by the United States. The bomb consisted of a bomb-shaped casing with over a thousand compartments, each containing a hibernating Mexican free-tailed bat with a small, timed incendiary bomb attached. Dropped from a bomber at dawn, the casings would deploy a parachute in mid-flight and open to release the bats, which would then disperse and roost in eaves and attics in a 20–40-mile radius (32–64 km). The incendiaries, which were set on timers, would then ignite and start fires in inaccessible places in the largely wood and paper constructions of the Japanese cities that were the weapon's intended target.

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