Many arguments both for and against the transmission of side have been put forward by rival experts, but in spite of all that has been said,and written the point cannot be regarded as settled. I propose here to settle down one or two arguments in favour of the theory that side cannot be transmitted from a cueball to an object ball.
To begin with, a billiard ball has a perfectly smooth surface, or, at least, as smooth a surface as human ingenuity and skill can impart to it. Under the microscope it will be seen that this surface presents many minute irregularities, but there is no evidence of anything sufficiently pronounced to set up an appreciable amount of friction. Therefore, as a scientific proposition it follows that between two surfaces too smooth to grip each other it is impossible to transmit rotary movement except by the exercise of great pressure. But, as a billiard ball responds to the least pressure by moving out of the way, it is undeniable that as far as this theory goes side cannot be transmitted.
In practice, too, as far as calculated experiment can take us, it does not seem possible to transmit side. This appears to be proved by asking a hand stroke expert to spin a ball as fast and as long as he can. Then, very carefully, place another ball in contact with the revolving ball and watch the result. There is no transmission of side or anything approaching it. The ball struck by the whirling sphere simply rolls off an inch or two without any semblance of.spin on it, and it must be admitted that as far as it goes this experiment is conclusive evidence against the transmission of side.
But I shall be told that in actual play the transmission of side is actually allowed for by leading exponents,and constitutes one of the greatest refinements of their art. They base their contention on the course taken by an object ball after contact with a cue-ball loaded with side, and will take up a cue and show that a powerful stroke played with side will cause the object ball to take an angle or reflexion from a cushion which they consider can only be explained by transmitted side. This would be conclusive but for the fact that the course of the cue-ball can be influenced by side before contact with the object, and what perhaps happens is that the effect of this deflection of the cue-ball on the object ball is mistaken for the transmission of side.
Further, the use of side, especially in conjunction with screw, enables strokes to be made by an infinite variety of contacts, and this factor, even when the cue-ball does not swerve may account for many of the things which,are held to prove the transmission of side. As regards the angle taken by an object ball after contact with a cushion it is well known that force alone will produce precisely the same effect as. that often.attributed to the transmission of side.
Before leaving the subject I should like to explain that my remarks only refer to a ball away from a cushion or another ball. I am quite willing to admit that side can be transmitted to a ball tight against a cushion or when all three balls kiss together. But even then I question very much whether enough is known about the matter for it to be of the least vise to any billiard player.