Probably a master rod with link rods – the only variant I’ve seen is the early twenties "slipper rod" style – the Glen Curtiss museum in Hammondsport had a cutaway Rhone Rotary – a radial in which the cylinders rotated en masse – with slipper rods.

I’m dying to know what the power impulses are – does this thing fire each cylinder sequentially – five power impulses per rotation? Seems like balancing would be a challenge.