It's a fairly common way to convert an old horizontal to vertical. Vertical heads are getting scarce for machines that are +/-100 years old.that's really bizarre
Anyone feeling super generous and willing to pick up and store this for me? haha@gmihovics some mills have both horizontal and vertical spindles, and they are way cool. Get a picture of @kevin.decelles CNC mill, and you'll see. The Normal Bridgeport type of mill is not well suited to use as a horizontal mill.
This is/was a true horizontal mill, and there was an adapter plate to mount the vertical Bridgeport spindle to it. I can see the horizontal spindle and the belt arrangement in the photo. This is a promising buy IMO.