Letter: Bowling theories bounced off course

I READ the article 'Whatmakes a ball swing?' (7 August) with interest. I am not an aerodynamist but have bowled the occasional ball. After discussing factors related to swing such as air flow, turbulence and pressure, the writers postulate delivery with the polished smooth 'face to the fore and the seam pointing at the slips, about 15 degrees to the side of the line of flight of the ball'.

The further discussion appears to assume that the ball maintains this same orientation (seam to the slips) after it leaves the bowler's grip till the first bounce, and presumably even after that, since it is any deviation of flight after the bounce that really outwits the batsman.

This is manifestly absurd. The bowler mighthave some control on the orientation of the seam till the first bounce only if delivery is without imparting rotations but certainly not after it bounces.

Interesting though the wind tunnel experiments are, it is difficult to see how these results can be applied to practical bowling.

Chandra P de Fonseka

Bristol