Yes, it’s three tractors in one. A British farmer called George Pryor needed more power than the tractors of the time could provide so he got the idea of combining two. Having built a working prototype he took the idea to a nearby tractor dealer, Ernest Doe, who refined it and went on to make nearly three hundred before the availability of more powerful, 4wd tractors made the idea irrelevant.
This particular one used two Ford Super Majors which are attached by a pivot which is turned hydraulically. The driver sits on the rear tractor and the control inputs are duplicated by hydraulic and mechanical linkages to control each element.
But that wasn’t enough. This one has a third element towed behind. This one isn’t steered like the front two but is just attached to a conventional hitch. To control it, the driver has to turn around and haul levers to operate the clutch and gearchange while simultaneously operating the other two elements. Depending on need you started one, two or three engines. When I saw it just the one was in use.
So there you have it. Innovation in the agricultural field.