Shaper

It looks fascinating! What does it do?

@Vinca The upper slide assembly has a cutting tool fixed to it.
It cycles in and out to provide the cutting action.It can be adjusted for the length of it's stroke to reduce extra movement when not needed or increase it for bigger work.
The cutting tool is fixed to what is called a clapper box that assures that there is no pressure on the cutting edge when it is moving backwards to prep for the workpiece feed to advance it for the next pass.
The lower casings of the machine are used to move the work in both the X and the Z axis while the tool moves in the Y.

The X axis is traversed automatically from side to side. The amount of feed rate can be set to either course feeds to rough cut the work, or decreased in movement for final sizing and finishing.

The work is traversed in the Z axis for removing material in a vertical direction. The knee moves the work up and down in the Z axis to determine how much material gets removed per pass.
The added monkey-motion of the upper slide that moves with each pass added wear to it that decreased the accuracy of the machine as time went on.
Shapers were eventually replaced by rotary milling machines with multiple edge cutters to increase the efficiency. Rotary spindles have greater wear properties as well.
Shapers are basically lost in time as the machining world moves forward on a daily basis, so this one is now relegated to museum status as a reminder of the past in a place where the history of older machinery is celebrated.