I have this camera. The lever adjust is a multi-position tensioner for the shutter spring. It is actually a two position lever from my experience, and if you go too far (the third position) then it's "off it's rocker".
It took me months to determine that mine was a Thornward Dandy, beings it was unlabeled. If your camera is the 4x5, you can configure them to use the standard 4x5 film holders.
If you like I can show you how to set up that shutter with a proper string. That wire thing between the spring and shutter is most unoriginal I suspect. I would be very surpised if it works with a wire.