>Hog rings are clamped around the end of a sausage casing to keep all
>the sausage meat inside.  Mystery solved!
>
Well, actually I think they are used on live hogs.  Hogs are very good 
"rooters".  They dig up the earth with their snouts looking for stuff to eat 
- roots, etc.  On a farm, you really don't want all this so you put in a hog 
ring(s).  When they root, it hurts and they stop.  It is put into the 
cartilage between the nostrils or they will put three in around the edges of 
the snout - left, right and top.

Dean Aukes