While he was at work on these reckonings he dispelled one fallacy, which, notwithstanding, is commonly held by golfers to the present day. Most players think that when driving and following through well the ball hangs on the face of the club, as it were, for long enough for the club to do something in the way of guiding it. How brief is the time in which the actual stroke is made for good or ill was proved conclusively in a very striking manner, and that time was set down--the whole time of impact--as that in which the club, moving at 300 feet a second, passed through about four times the linear space by which the side of the ball was flattened. Putting this space down, nowadays, at about ⅛ in., and reckoning the time that it would take the club going at the speed indicated to cover that small distance, we have the fact that the duration of impact is only about 1/7000th of a second, and that that is the whole time that the golfer has for the guiding of the ball! As the Professor said, “the ball has, in fact, left the club behind before it has been moved through more than a fraction of its diameter”; and in the case of the gutta, with the smaller extent to which it flattened on the club, he came to the conclusion that the duration of impact was far less than that which has just been mentioned. Incidentally in this connection he took occasion to expose another of the golfer’s fallacies as to the effect of wind on the flight of the ball, in the following words: “It is well to call attention to a singularly erroneous notion very prevalent among golfers, namely, that a following wind carries a ball onwards! Such an idea is, of course, altogether absurd, except in the extremely improbable case of wind moving faster than the initial speed of the ball. The true way of regarding matters of this kind is to remember that there is always resistance while there is relative motion of the ball and the air, and that it is less as that relative motion is smaller, so that it is reduced throughout the path (of flight) when there is a following wind. Another erroneous idea somewhat akin to this is that a ball rises considerably higher when driven against the wind, and lower if with the wind, than it would if there were no wind. The difference (whether it is in excess or deficit will depend on the circumstances of projection, notably on the spin) is in general very small; the often large apparent rise or fall being due mainly to perspective as the vertex of the path is brought considerably nearer to or farther from the player.”