Load carrying unit

Claim 1

A LOAD SUPPORTING DEVICE INCLUDING A PLATFORM, AND AT LEAST THREE LOAD SUPPORTING UNITS MOUNTED ON SAID PLATFORM, EACH UNIT COMPRISING A HOLLOW MEMBER HAVING TWO OPPOSED END FACES, AN EXTENSIBLE WALL CONNECTING THE END FACES TO FORM A CLOSED SPACE AND PERRMIT THE DISTANCE BETWEEN THE END FACES TO VARY, MEANS DEFINING A CUPSHAPED CAVITY ON ONE OF THE END FACES OF THE SIDE THEREOF OUTSIDE THE CLOSED SPACE, AND INCLUDING A RIM FOR COOPERATION WITH A SUPPORTING SURFACE OR THE LOAD, FLOW RESTRICTING INLET MEANS FOR NORMALLY SUPPLYING AN UNINTERRUPTED FLOW OF PRESSURISED FLUID TO SAID CLOSED SPACE, AND FLOW RESTRICTING OUTLET MEANS CONNECTING SAID CLOSED SPACE TO THE INTERIOR OF SAID CUP-SHAPED CAVITY THROUGH WHICH THE FLUID SUPPLIED TO SAID CLOSED SPACE NORMALLY FLOWS INTO SAID CAVITY TO FORM A CUSHION OF PRESSURISED FLUID THEREIN EFFECTIVE TO MAINTAIN A RESTRICTED FLUID ESCAPE GAP BETWEEN SAID RIM AND THE SURFACE OR LOAD.