20 



Art. 9. -T. Terada: 



times very large, in one instance amounting to 5'4 ï with a period 

 of 1-2 minute (see Fig. 6, A). The amplitude is generally 

 damped gradually, with a sensibly constant period. On closer 

 examination, cases were also found where the period of the waves 

 changed gradually in an apparently coherent train. Sometimes, 



Fig. 7 (f original size). 



'^^nt 13. 19)3. M^-^r 



1 Dec. 7. AT = +5"' 



