Forbes-robinson

Claim 1

IN A CAMERA TRIPOD HEAD, A BASE PROVIDED WITH MEANS FOR ATTACHMENT TO A TRIPOD, A CAMERA SUPPORTING MEMBER DISPOSED ABOVE SAID BASE AND PROVIDED WITH MEANS FOR ATTACHING A CAMERA THEREON, AND SEPARATE DEVICES INTERPOSED BETWEEN SAID BASE AND SAID MEMBER AND MOUNTING SAID MEMBER ON SAID BASE WITH CAPACITY FOR MOVEMENTS OF SAID MEMBER RELATIVE TO SAID BASE ABOUT A HORIZONTAL AXIS AND A VERTICAL AXIS RESPECTIVELY; EACH OF SAID DEVICES INCLUDING FLUID DAMPING MEANS IMPOSING DAMPING RESISTANCE TO MOVEMENT OF SAID MEMBER RELATIVE TO SAID BASE ABOUT AT LEAST ONE OF SAID AXES; SAID FLUID DAMPING MEANS COMPRISING AN ENCLOSED CAVITY BOUNDED IN PART BY CLOSELY SPACED, PARALLEL WALL SURFACES MOVABLE RELATIVELY TO EACH OTHER INCIDENT TO MOVEMENT OF SAID MEMBER ABOUT THE AXIS WITH WHICH THE CAVITY IS ASSOCIATED, A VISCOUS FLUID IN SAID CAVITY CONTACTING SAID WALL SURFACES AND BY REASON OF ITS COHESIVE AFFINITY FOR SAID SURFACES AND ITS RESISTANCE TO SHEAR, IMPOSING YIELDING RESISTANCE TO SAID RELATIVE MOVEMENT, A PAIR OF CONTACTING AND CORRESPONDINGLY RELATIVELY MOVING BEARING SURFACES DISPOSED ADJACENT TO AND SUPPORTING ONE EACH OF SAID WALL SURFACES IN PARALLEL RELATION TO THE OTHER WALL SURFACE AND HAVING A FRICTIONAL RESISTANCE TO THE SAID RELATIVE MOVEMENT THEREOF WHICH IS SUBSTANTIALLY LESS THAN THE RESISTANCE OFFERED BY SAID FLUID, A SEALING MEANS ASSOCIATED WITH SAID BEARING SURFACES EFFECTIVE TO RETAIN SAID FLUID IN SAID CAVITY, AND MANUALLY OPERABLE MEANS DISPOSED WHOLLY EXTERIORLY OF THE ONE OF SAID CAVITIES ASSOCIATED WITH ONE OF SAID AXES OPERABLE TO RELEASABLY LOCK SAID MEMBER AGAINST MOVEMENT ABOUT SAID ONE OF SAID AXES.