90 WAVES OF THE SEA 



observer is too late in his determination of the time 

 of breaking for any wave, he not only makes that 

 interval too long, but the next too short. Thus 

 we see that we had here a fairly uniform series 

 of waves whose average period, 19 seconds, shows 

 that their velocity, when in deep water, was 57 

 knots, or 66.5 statute miles, per hour, and their 

 average wave-length 1,850 feet. 1 



It was not easy to make exact comparison 

 between the height of these breakers and those 

 which I have seen at Branksome Chine during 

 storms, for the latter break farther out and in 

 deeper water. However, the impression conveyed 

 to the eye is that there is no very great difference 

 between the heights of the breakers above the water 

 in front of them in the two cases. Branksome 

 Chine is sheltered from the west by the promontory 

 called Pur beck Island, so that the waves of 

 westerly gales and the swell which follows are both 

 reduced by change of direction in rounding the 

 promontory. If, however, we recall to mind the 

 numerous references in nautical writings to the 

 great breakers which come in during calm weather 

 upon oceanic islands and other shores directly ex- 

 posed to the ocean, we shall recognise that their 



1 This is about equal to the distance from Park Lane to 

 Devonshire House, measured along Piccadilly. 



