The tops of the wing gear and adjacent body gear struts were inter-connected with a two inch(ish) diameter pressure balance line so that excess pressure buildup in one gear on one side during landing and taxi, could be "shared" with the other gear on that side. The line was filled and bled via a service port and I suppose you could think of it as a hydraulic spring. I heard the DC3 has a similar arrangement but don't quote me on that. In service it was found to be unnecessary because the gears worked together just fine and I think it was gone by the time the -200's appeared.