2. Bat bombsThese were developed in World War II by US. It consisted of bomb shaped casings with various compartments. Each compartment had a Mexican free tailed bat with a small 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 rest in nests and tree hideouts.
The incendiaries would start fires in inaccessible places in the largely wood and paper construction of the Japanese cities that were the weapon's intended target.