HEIGHT 23 



we can learn these measurements, made according to the method pro- 

 posed by Arago [see p. 61] and reported by him, 2 were the first that 

 were ever reported of waves at sea measured by any dependable 

 method.) Similarly, the largest waves observed from H. M. S. 

 Challenger during her historic scientific crifise around the world, 

 1873-75, were only 18 to 22 feet high (southern Indian Ocean between 

 Crozet Island and Kerguelen), 3 while the maximum height reported 

 by United States naval officers from any part of the ocean during the 

 three years, 1883-86, was 25 feet (Gaillard, 1904, p. 76). 



The maximum heights of storm waves. — The heights of the largest 

 waves that ships encounter at sea during severe storms is a matter of 

 perennial interest, and published statements have varied widely. We 

 have just pointed out that the vast majority of waves are less than 12 

 feet high in all parts of the ocean, and that waves higher than 25 feet 

 are not common. But it is well established that waves may grow to 

 40 or 50 feet — or even higher when a really severe gale extends over 

 an area great enough to have an effective fetch of 600 to 800 miles. 

 The earliest definite measurements by a dependable method of storm 

 waves of that general order of magnitude, with which we are ac- 

 quainted, were made in February 1841 near the Azores by Lt. de 

 Missiessy, during a violent gale of 2 weeks' duration ; he reported wave 

 heights of 43 to 49 feet. 4 More recent reports of waves higher than 

 35 feet out at sea (mostly from Gaillard, 1904, and Cornish, 1910 

 and 1934) are listed below. 



North Atlantic : 



Waves with average heights of approximately 30 feet, the largest 

 (about one in every six) about 43 feet high, observed by Dr. Scoresby 

 midway between Newfoundland and Ireland (lat. 51° N., long. 

 38° 50' W.) on March 5, 1848. 



A maximum height of about 35 feet observed at Peterhead, Scot- 

 land, in February 1900. 



Waves of at least 40 feet which forced the Normania to put back to 

 New York from halfway across the Atlantic, because of the damage 

 done to her upper works, in January 1894. 



Waves commonly 29 feet high, but some of them 43 feet high, en- 

 countered by the Ivernia off the west coast of Scotland on Decem- 

 ber 7, 1900. 



A huge swell, with many waves up to 41 feet high, encountered 

 by the Minnehaha, eastbound from New York to Southampton, in 

 latitude 48°54' N., longitude 18°20' W., on February 9, 1907. 



2 Arago, D. F. J. 1841. Plus grande hauteur des vagues. C. R. Acad. sci. Paris, 

 vol. 11, p. 326. 



3 Tizzaid, T. H., and others. 1885. Rep. sei. res. * * * H. M. S. Challenger. 

 vol. 1. Narrative, pt. 1, p. 330. 



4 Arago, D. P. J. 1857. Oeuvres completes. Paris, vol. 9, p. 550. 



