old Prontor cameras

[Michael Summers]

well for the holidays i got an old antique Prontor camera almost like this one here:

http://www.gold-camera.com/photo/pictures/PRONTOR-S1938.jpg

i was wondering, once you fold out the lens and you here the "click" how do you collapse the lens? if anyone knows info on old cams, i'd like some advice.

thanks!