It looks like an attempt to make a radial arm saw without infringing on some critical patents. If there is a data plate still attached and readable, it should tell who the vendor was. The shape of the base should help identify it.
Actually pre-dates the radial arm saw. Swing saws were made to allow the use of a line belt to drive the mechanism. If the swing radius was set up correctly, the line belt could drive it throughout the swing. The design carried over into lumberyard and home workshop use with the addition of an electric motor, but a safer (ironic in our current way of thinking) design was found in the radial arm saw, so this saw never really got much production.
King Seeley was the maker for Sears. It's badged Craftsman.
I think where this will end up is as a base for the Ameribrade belt grinder I have on order. I was too cheap to pay $270 for their stand, figured I'd set it on the bench or find a stand. This is heavy/stable enough to do, and height is pretty much right, and adjustable shorter if needed.
I also had thought about using it as an abrasive saw for metal, but it's bigger and clumsier than needed for that. Or as a vise stand, that had occurred to me that it would work real well, but I have 7 bench mounted vises now that pretty much cover my needs.