Underwater sleds

Claim 1

A MARINE VEHICLE COMPRISING: A HULL HAVING A MAN-CARRYING COMPARTMENT WHICH IS OPEN TO ENTRY OF WATER FROM THE SURROUNDING BODY OF WATER IN WHICH THE VEHICLE IS LOCATED; BALLAST TANKS IN SAID HULL EACH HAVING UPPER AND LOWER PORTIONS AND LOCATED ON OPPOSITE SIDES OF THE MANCARRYING COMPARTMENT, SAID TANKS BEING ADAPTED FOR PROVIDING SUFFICIENT BUOYANCY TO MAINTAIN THE VEHICLE AFLOAT NOTWITHSTANDING THE PRESENCE OF WATER IN THE MAN-CARRYING COMPARTMENT; MANUALLY CONTROLLABLE MEANS MOVABLE IN A GIVEN DIRECTION FOR ADMITTING WATER INTO SAID BALLST TANKS FOR CAUSING SAID VEHICLE TO SINK; A WATERPROOF HOUSING IN SAID HULL; AN ELECTRIC MOTOR OPERATIVELY MOUNTED WITHIN SAID HOUSING; AND WATERPROOF ELECTRIC POWER-SUPPLY MEANS OPERATIVELY CONNECTED TO THE ELECTRIC MOTOR FOR ENERGIZING SAID ELECTRIC MOTOR; SAID VEHICLE FURTHER COMPRISING A NORMALLY CLOSED AIR OUTLET VALVE FOR SAID TANKS; MEANS CONNECTING SAID VALVE BETWEEN THE UPPER PORTIONS OF SAID TANKS AND THE EXTERIOR OF THE VEHICLE; A CONTROL HANDLE ON SAID VALVE MOVABLE FROM A FIRST POSITION IN WHICH SIAD VALVE IS CLOSED TO A SECOND POSITION IN WHICH SAID VALVE IS OPEN; AND LINKAGE MEANS CONNECTED TO THE MANUALLY CONTROLLABLE MEANS FOR ENGAGING THE CONTROL HANDLE AND MOVING THE SAME OF ITS SECOND POSITION UPON THE MANUALLY CONTROLLABLE MEANS BEING MOVED IN SAID GIVEN DIRECTION.