I have long been aware of bats being a gentle, beneficial part of our ecology. But I was amazed when I heard of a top secret unit in World War II working on developing a bat bomb.
The idea was conceived by a Pennsylvania dentist name Lytle S. Adams. He was a friend of Eleanor Roosevelt. He outlined a plan to arm bats with bombs that could be ignited to start fires. The plan was accepted and sent to the military under top secret status.
First, a container bomb was developed to house a thousand bats. This is a container bomb from Wikipedia. It had layers of trays inside to divide bats. Each bat was equipped with a small incendiary device strapped to it. Louie Fieser, inventor of the nepalm, designed half ounce and one ounce timed incendiary devices for the creatures.
The plan was to drop the container bomb from 5000 feet. A parachute would be attached to the bomb. The bats would be released around 1000 feet. The bats would disperse to varies places. In the morning they would hide in the cracks of the highly flammable Japanese buildings. The timed devices would then be ignited, causing widespread fires.
Plans were made to have ten B-24 bombers from Alaska carry a hundred bat shells. This would release 1,040,000 bat incendiary bombs over the industrial cities of Osaka Bay.
Picture from Wikipedia
Another test in Utah included a fake Japanese village built for demonstration. Those watching felt the bombing was a success.
The program was cancelled in 1944 after spending two million on development. It was felt that the research was progressing too slow. It was reported that the founder of the idea made a statement saying we could have devastated Japan with the bat fires and sustained very little loss of life. Instead we sent an atom bomb.