...and large flash bulbs of the time used ordinary
Edison screw bases.
Not something that you'd want to put into your bedside reading lamp...
ALthought I beleive some of types were designed to be fired by
mains-voltage AC. A book I have just picked up lists a 'Syncho-Press No
21' which is described as 'operates on voltages ranging from 3 to 125,
direct or alternating current'
-tony