"When my wife and I were in Europe last year, the tour guides showed us a couple of churches that had a turntable built into the wall. You could anonymously put your baby on the turntable, turn it and then ring a bell and that would signal to the people inside to come check the turntable. "
That scenario showed up on an episode of MASH in the 1970s. Convent, turntable, bell, whole scenario.