A delightful little video about a foot-powered cam hammer, probably for peening scythes. 

 

I think the rod he was wondering about is a brake, may be missing the shoe. When he pulled the lever it slides the rod up a slight ramp so it will contact the hub.

Someone suggested in one of the comments that it might be an adjustable support for the snath.

It wouldn't be a brake, you can the treadle mechanism and wheel, with your foot just like a spinning wheel with that treadle to crank mechanism.

I don't think the folding leaver thingy is a snath support it's too fragile and if the hammer is for peening scythes I'd bet the operator laid the snath on something behind him/er or maybe in the crook of an arm or over a shoulder. That way the edge would be facing him/er and more clearly visible. 

The ball on the end does speak for a female connection to something, I just can't see it being a brake, even a parking brake. The ONLY thing I'm sure about that folding leaver thingy is it was a significant part of the machine missing the business end. <sigh>

I'd sure like to know what attachments were kept in the box.

Frosty The Lucky.

 

It's interesting that each joint of the folding lever appears to have a toggle to lock it in the straight position. 

Yes and stops so they won't fold the other way. I THINK. 

Knowing what other anvil dies and hammers were used in it might explain it. At 3:59 in the video is a clear view of the band and set screw holding the hammer handle.

Frosty The Lucky.