TIME OF EARTHQUAKE AND HATE OF PROPAGATION OF SHOCK. 



$5 



earthquake! wave 01 shock as full in its progression from place to place over 

 the surface of the affected area.'V 1 ) 



The data obtained from the Indian seismographic records are as 

 follows : — 



Rangoon. — The Omori seismograph installed in the Rangoon 

 College.— The shock commenced on the morning of the 23rd May 

 at 8 hours 54 minutes 10 seconds, and lasted till 10 hours 

 3 minutes 30 seconds (B.S.T.). The shook was severe from 8 

 hours 54 minutes 10 seconds till 9 hours 13 minutes 30 seconds. 

 The clock whose pendulum swings from cast to west Stopped as 

 soon as the shock commenced. 



Through the courtesy of the Principal of the Rangoon College, 

 1 have been allowed to examine the original record taken by 

 this instrument, but I do not, think that, any farther evidence 

 can be safely deduced from it. owingto (he violence of the motion 

 consequent upon the short distance of the station from the 

 epicentre, and the unsatisfactory condition of the dock. 



Kodaikanal. — A good record was obtained from the instrument 

 of the Milne type in this observatory (PL No. !<>)• 



(All times given in this and subsequent data are referred to 

 Greenwich Mean Time.) 



Time of commencement oi Preliminary Tremors, 2 hours :?!••<> minutes. 

 5> » .. .. Long Wave, 2 hours 29*6 minutes. 



,, ,, Maxima, 2 hours 39-9 minutes. Maximum Amplitude, 1 3*5= 5-4 mm. 



n „ » 2 ., 42-0 „ . n n 14-r,- 5-8 mm. 



„ - .. 2 ,. 47!i „ . „ ., 16-0=60 mm. 



End j (> hours M>«2 minutes. Duration, '■) hours 4ii-2 minutes. 



AUpore (Calcutta). — The record from the Milne instrument in 

 this observatory was not satisfactory. Owing to air tremors the time 

 of the commencement of the preliminary tremors cannot be given. 

 The large movement is stated by the meteorological reporter 

 to commence at 2 hours 26*1 minutes (?), but I think that this 

 is very much open to question, after an inspection of a copy of 

 the record. Owing to the boom moving throughout the trace, 

 the time of maximum and the amplitude cannot be deduced. 



The movement ended at 6 hours 1*9 minutes (?)• 



Sensibility, 1 mm =0*38 of til;. 



1 C. S. MiddlemiflB : hoc. ril.. pp. 290 and 291. 

 Bee also Publications of tin- Earthquake Investigation Committee in Foreign 

 l.aii^na^ (>s No. 21. p. 26. 



La Science Seismologiaue, by LeCotntede Montessusdo Ballore/p. 10, 



