Practice golf club and tethered ball

Claim 1

A GOLF CLUB ADAPTED TO INDICATE THE QUALITY OF A PRACTICE SWING COMPRISING; IN COMBINATION; A SHAFT; A CLUB HEAD; SAID CLUB HEAD INCLUDING A SUBSTANTIALLY PLANAR FACE SURFACE, A BODY WHICH EXTENDS REARWARDLY THEREFROM TO AN ARCUATE REAR SURFACE, A TOP SURFACE, AND A SUBSTANTIALLY PLANAR BOTTOM SURFACE POSITIONED WITH RESPECT TO SAID SHAFT FOR STRIKING ENGAGEMENT WITH THE GROUND DURING SAID PRACTICE SWING; AND MEANS FOR COUPLING SAID SHAFT TO SAID CLUB HEAD SUCH THAT THE AXIS OF SAID SHAFT BOTH LIES IN A PLANE SUBSTANTIALLY PARALLEL TO THE PLANE OF SAID FACE SURFACE AND IS ANGULAR TO THE PLANE OF SAID BOTTOM SURFACE; SAID CLUB HEAD INTEGRALLY INCLUDING A DEPRESSION IN SAID TOP SURFACE THEREOF IN THE FORM OF A STRAIGHT, HOLLOW, OPEN-ENDED CHANNEL COMMENCING AT SAID FACE SURFACE AND EXTENDING REARWARDLY THEREFROM THROUGH SAID REAR SURFACE; SAID DEPRESSION DESCENDING DOWNWARD FROM SAID TOP SURFACE TOWARD SAID BOTTOM SURFACE SUCH THAT THE DEPTH OF SAID CHANNEL IS SUBSTANTIALLY COEXTENSIVE WITH THE VERTICAL DIMENSION OF SAID CLUB HEAD, AND ONLY A THIN BRIDGE EXISTS BETWEEN THE BOTTOM OF SAID CHANNEL AND SAID BOTTOM SURFACE; THE WIDTH OF SAID CHANNEL THROUGHOUT ITS ENTIRE LENGTH BEING OF SUFFICIENT DIMENSION TO ADMIT PASSAGE OF A GOLF BALL THERETHROUGH.