So, let's say I have a 15V battery connected to an old-fashioned flash bulb. Would completing the circuit fire the bulb and then automatically disconnect the circuit safely?

Furthermore, what methods are used to trigger a camera to make an exposure autonomously? I know that Edgerton used sound to trigger his flash, but that means the shutter would have to be open beforehand. How about triggering a shutter as well? What kinds of cameras support this, what kinds of triggers, etc?