230 LIGHT SCIENCE FOR LEISURE HOURS. 



Samoan Islands. But he adds, that " where the shore 

 is shelving, there will be first a retreat of the water, 

 and then the wave will break upon the beach and roll 

 far in upon the land." This is precisely what happened 

 when the great wave reached the eastern shores of 

 New Zealand, which are known to shelve down to 

 very shallow water continuing far away to sea toward 

 the east. 



At about half- past three on the morning of August 

 14th, the water began to retreat in a singular manner 

 from the port of Littleton, on the eastern shores of the 

 southernmost of the New-Zealand Islands. At length 

 the whole port was left entirely dry, and so remained 

 for about twenty minutes. Then the water was seen 

 returning like a wall of foam ten or twelve feet in 

 height, which rushed with a tremendous noise upon 

 the port and town. Toward five o'clock the water 

 again retired, very slowly as before, not reaching its 

 lowest ebb until six. An hour later, a second huge 

 wave inundated the port. Four, times the sea retired 

 and returned with great power at intervals of about two 

 hours. Afterward the oscillation of the water was 

 less considerable, but it had not wholly ceased until 

 August 17th, and only on the 18th did the regular ebb 

 and flow of the tide recommence. 



Around the Samoa group the water rose and fell 

 once in every fifteen minutes, while on the shores of 

 New Zealand each oscillation lasted no less than two 



