To prevent the generation of seizure when high load is applied at a low speed, or when the machine is started or stopped by supplying a pressurized lubricating liquid to a pocket in the bearing face to enable the contact surfaces not to be in direct-contact with each other even in a standstill state.

A pocket 12 is formed in a plane part 11 of a lower bearing 8 sliding along an upper bearing 7 for supporting a lower surface plate 6, and a water pressure supply pipe is connected to the pocket 12. When the bearings are started to operate, pressurized water is supplied from an external, pressure generating means to the pocket 12 to form a liquid film on the plane part 11, and thus to prevent seizure. Further, by replacing the lubricating liquid with water, installation and operation of the machine in the environment where oil component such as lubricating oil is objectionable, become possible.