Because I don't see a photo...I'll have to assume you're talking about a Case Stationary Hay Press. They were common (IHC made a lot of them too) before the pull behind stationary engine driven hay balers of the 1940's were introduced.
The early hay presses ran off hit & miss engines that drove a shaft that attached to a pressing arm. Square wood blocks were placed in the press...then lose hay was pitch forked into the press, and "pressed" down onto the first block by the press arm. A second wood block was placed on top of the pressed hay and the process reapeated itself.
Bailing wire was then inserted around the pressed hay bail, then twisted to secure it. The wired hay bail and the wooden press blocks were then kicked out the back of the bailing shoot and the process began again.
Hay presses are a good two to three man opporation process.