Athletics of To-Day 1929

342 Athletics of To-day The diagram given in Fig. 55 shows the path described by the shot in its passage through the air. SA is the final and main propulsive force, accumulated in the glide and generated in the jerk which comes from the left foot resistance, right foot push, and the arm drive. It is obviously a "short" effort, in comparison with the length of the flight parabola ABD. The initial line of projection AC pronounces the correct delivery angle of 45 degrees from which the parabolic path ABD is entered upon. FIG. ss If the average performance of the first three men throughout the National hampionships in all countries during rgz8 is examined it will be found that the world's standard has now risen to approximately 45ft. In a put of that distance there is exerted a kinetic force of about 36r foot-lb., the shot leaves the hand with an initial velocity of 38ft. per second, and the time taken to complete the range (r), or 45ft., is r.7 sec.