AND OTHER WATER WAVES 69 



accompanied by a swell from the south-west. 

 Lieutenant Paris made regular observations of 

 waves during the whole of this voyage, and when 

 cruising in the seas of China and Japan, but his 

 opportunities of measuring large ocean waves 

 occurred only in the southern ocean, and principally 

 during the storm above referred to. For obtain- 

 ing data as to the size of full-grown storm -waves 

 from his valuable paper, we are, in fact, almost 

 restricted to a single day's observations, but the 

 value of this day's work is greatly enhanced by 

 his daily practice in observing. His method, as 

 he explicitly states, is that of Dr. Scoresby, the 

 wave-lengths being usually obtained by noting the 

 time occupied by the wave in running the length of 

 the ship combined with the interval elapsing be- 

 tween the arrival of the waves. The height he 

 calculates as equal to that of the eye when the 

 wave just obscures the horizon ; but his observa- 

 tions in this respect are superior to Dr. Scoresby's, 

 for, by nimbly running up or down the shrouds, 

 he got on a level with each succeeding wave, and 

 was not reduced to Scoresby's expedient of guessing 

 the height above him of the largest waves. His 

 results are as follows. On October 25th, 1867, 

 between the Cape of Good Hope and the Islands 

 of St. Paul and Amsterdam, during a strong gale 



