190 WAVES OF THE SEA 



stones to be much less than it really is. Mr. 

 Nelson B. Richardson and I arranged an experi- 

 ment upon the rate of travel of materials of which 

 he has given a full account. 1 



On the beach opposite Fleet Coastguard Station, 

 in a slight breeze from NNW., with breakers 2 feet 

 high, and a current running eastwards at i foot 

 per second, a brickbat, or half -brick, travelled 56 

 yards in 2\ hours. Supposing this wind to remain 

 constant, the shingle would not travel westwards 

 even when the current is running to the west. 

 Therefore, allowing six hours out of every twelve 

 for the east -running current, which is less than 

 what it is, the brickbat would then travel from 

 Bridport Harbour to Chesilton (18 miles) in 108 

 days. Given strong wind from the westwards, 

 the time of transit would be very much less. 

 Another brickbat travelled 574 yards to the east- 

 ward in 28 hours, which would make the time of 

 travelling the 18 miles 142 days during fine 

 weather. A stone, 4 inches long, which was caught 

 by a wave, appeared to move more quickly than 

 either of the brickbats ; but even if the stones 

 were moved somewhat more slowly than the brick - 



1 " An Experiment on the Movements of a Load of Brickbats 

 deposited on the Chesil Beach," by Nelson B. Richardson, B.A. 

 (Proceedings of the Dorset Field Club^ vol. xxiii., 1902). 



