versions of the Whittemore board-mounted lathe parer used a spiral-cut
shaft to advance the apple past a stationary blade and then the slicer.
In the design above Whittemore switched to using a spiral-threaded shaft
to advance a curved blade/slicer assembly past a rotating apple. Note
the spiral thread is a wire wrapped around the shaft. After the apple
is pared an upward curve in the wire guard allows the blade/slicer assembly
in the starting
position for the next apple. See
the next slide to view the label on this parer.