I have several photos of knife froes, all probably 19th Century. 
However, I don't have the means to post them on this list.  I can send
them as attachments privately to someone able to post them on list. 
They're apparently uncommon, though not really rare,  What I have found
are all handled like the tobacco cutter.  I found them in my research on
coopering (the heads are dowelled together), but useful to any craftsman
who needed 2 to 4 inch dowels, for doors, window sash, wainscotting,
etc. 

Mike in Woodland