It's a slicer for something, and certainly old,
but for what?

http://cgi.ebay.com/_W0QQitemZ400032413691

If it's for pasta, the pasta would already have
to be cut into wide strips before using this to
cut it into narrow strips. What would be the
point of that? If you already have the knife
in your hand, why not keep cutting and forget
about using this machine?

It could be for cutting some other material
into strips, a material that occurs naturally
in wide strips. Like maybe slitting bark or
something for weaving into baskets.