Apidictor

An apidictor is an instrument which measures and records the sound in a beehive. The instrument records the aggregate sound made by the buzzing of the bees' wings, and may help with predicting when a colony is preparing to swarm.^[1]

Edward Farrington Woods, a BBC sound engineer,^[2] invented and patented the apidictor in 1952,^[3] though he sold only 300 worldwide.^{[1][further explanation needed]}