Why golf balls have dimples

Sir, – Philip Reid's explanation ("Covering all the bases", Sport, September 3rd) for dimples on golf balls states that "flat or irregular shaped objects move in an inconsistent manner".

But a smooth golf ball is neither flat nor irregular. The reason dimples are added is to decrease drag and increase lift. Because of these aerodynamic effects, a dimpled golf ball travels twice as far as a smooth one, when hit with the same force. – Yours, etc,

SEAN McGIBBON,

Kilkenny.