But to return to the stumbling-blocks in the way of the correct performance of an act which requires one “to swing up and down in the same orbit.” These arise mainly from the tendency of the great majority to curve and shorten the spine unduly and otherwise to interfere with the correct conditions of the muscular system of the back, the spine, and the thorax in the performance of certain physical acts.[17] These tendencies are particularly marked when the arms are employed in such a movement as the “swing down” to make the stroke following the preparatory “swing up.” Consequently not one person in a thousand is capable of maintaining during the _down_ stroke those conditions of the back and spine present during the _up_ stroke. Consideration of these points will indicate that in order “to swing up and down in the same orbit,” it is essential that the position of the spine—particularly as regards its length and relative poise during the up and down movement—must be maintained. Other conditions are of course necessary but I cannot deal with more than one or two of the chief factors. In order to secure the proper use of the arms and legs correct mental guidance and control are necessary. Such guidance and control should, of course, be conscious. Furthermore, this mental guidance and control must co-ordinate with a proper position and length of the spine and the accompanying correct muscular uses of the torso, if these limbs are to be controlled by that guidance and co-ordination which will command their accurate employment at all times within reasonable limits. The foregoing are a few of the fundamental difficulties with which the golf teacher and pupil are beset. Those who have taken lessons will at once admit that the ordinary teaching methods fail to reach these difficulties satisfactorily. As a matter of fact they are not even taken into consideration. The orthodox teaching method holds the “end” in view and not the “means whereby.” It depends upon the giving of orders on the “end-gaining” principle, such an order, for instance, as “Swing up and down again in the same orbit,” without consideration of the “means whereby”; that is, without making certain that the pupil has the power to maintain a proper position of his spine and back and to use the limbs correctly during the performance of such physical acts. In other words, the teacher should first discover if his pupil is reasonably correctly co-ordinated in those muscular uses of his organism which are essential to the proper carrying out of instructions necessary to the performance of definite physical acts demanding co-ordination in the use of the human body and limbs. If these tests are not made the beginner will waste much valuable time, dissipate his energies, suffer needless worry and suspense, and become unduly apprehensive in his attempt to gain even a very moderate standard of dependable excellence in playing golf or other games to which he may devote himself.