Connect the items in the sequence: battery, resistor, capacitor, flash bulb then back to the other end of the battery.
No current flows until a bulb is pushed into its holder. The resistor limits the current so that the bulb doesn't fire when you push it in but it allows the capacitor to charge to the same voltage as the battery in a few seconds.
The contacts in the camera connect to the junction of the resistor and capacitor and the junction of the bulb and the battery. When the contacts close the capacitor is connected directly to the flashbulb and can discharge all of its stored energy into the bulb in order to fire it.


Steve.