TRAJECTORIES FOR VARIOUS SPEEDS 



337 



I purposely assumed 240 feet per second for the initial speed, though it is 

 greater by ten per cent, than any I have yet actually measured 1 , in order to give 

 this form of the theory as fair play as could be equitably conceded. Yet the 

 utmost attainable range, as shown by the table, is short of 160 yards, while the 

 players whose pace I measured had habitually carried about 180 yards the previous 

 day, or were to do it the next. But I measured their habitual elevation as well as 

 their pace. It was always small, rarely more than i in 6, i.e. less than 10. The 

 average was about I in 7, or little over 8. Look again to the table, and we see 

 that the maximum range for a speed of 240 (though only about 160 yards at best) 

 involves an elevation of some 34, altogether unheard of in long driving, while the 

 elevation of 10 gives a range of 108 yards only ! Thus this form of the theory 

 also breaks down completely. But, before we altogether dismiss it, let us test it in 

 two other and perfectly different ways. 



It might be objected to the reasoning above that I have taken initial data 

 from experiments on a limited number of exceptionally good players ; and that I 

 have somewhat arbitrarily assumed a value for the resistance of the air greater than 

 that given by one recognised authority and considerably less than that given by 

 another. One good, though only partial, answer is to change my authority so far 

 as elevation is concerned ; and, keeping to the same co-efficient of resistance, find 

 the characteristics of drives with various initial speeds. 



Some six years ago, Mr Hodge kindly measured for me, by means of a clino- 

 meter, the average elevation of drives made by a great number of good players 

 from the first tee at St Andrews. He estimated it at about i3'S. Bashforth's 

 tables usually involve data for whole degrees only, so I shall assume 14 as the 

 standard elevation. Here are the results for various initial speeds, some wholly 

 unattainable : 



Note, first, that in all these paths the time is much too short ; second, that the 

 initial speed required for a carry of 184 yards is 382 feet per second, which must 



1 In my laboratory experiments the players could not be expected to do full justice to 

 their powers. They had to try to strike, as nearly as possible in the centre, a ten-inch disc 

 of clay, the ball being teed about six feet in front of it. Besides this preoccupation, there 

 was always more or less concern about the possible consequences of rebound, should the 

 small target be altogether missed, 



T. 43 



