Piggy-back transportation system

Claim 1

A LOAD HANDLING AND CUSHIONING DEVICE, COMPRISING A LOWER BASE PLATE; AN UPPER PLATE DISPOSED IN A SUBSTANTIALLY HORIZONTAL PLANE THEREABOVE; GUIDE MEMBERS CARRIED BY SAID PLATES AND DISPOSED TO MUTUALLY INTERFERE TO LIMIT THE RELATIVE MOTION THEREBETWEEN, THE AREAS OF THE PLATES BEING LARGE AS COMPARED WITH THE MAXIMUM VERTICAL SEPARATION BETWEEN THE PLATES PERMITTED BY THE GUIDE MEANS; LOAD RECEIVING AND ENGAGING MEANS CARRIED ON SAID UPPER PLATE; PLURAL INFLATABLE AIR TUBE MEANS OF FLATTENED ANNULAR SHAPE INTERPOSED BETWEEN SAID PLATES AND MUTUALLY SPACED APART IN TWO NORMAL HORIZONTAL DIRECTIONS, THE MUTUALLY ADJACENT FACES OF THE PLATES HAVING OPPOSED BOWL-SHAPED CAVITIES RECEIVING EACH AIR TUBE MEANS, THE CAVITIES BEING DEEP ENOUGH THAT WHEN THE TUBE MEANS IS DEFLATED THE PLATES COME TOGETHER WITHOUT PINCHING THE PERIPHERY OF THE TUBE MEANS THEREBETWEEN, SAID LOWER PLATE HAVING AIR DUCTS, THERETHROUGH INDIVIDUALLY COMMUNICATING WITH EACH ONE OF THE AIR TUBE MEANS; AND INDIVIDUAL AIR SUPPLY LINE AND VALVE MEANS COUPLED TO EACH DUCT FOR SELECTIVELY INFLATING THE AIR TUBE MEANS TO RELATIVE DEGREES REQUIRED TO FLOAT THE UPPER PLATE SUBSTANTIALLY LEVEL ON THE LOWER PLATE DESPITE UNEQUAL DISTRIBUTION OF LOAD WEIGHT ON THE AIR TUBE MEANS.