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REPORT — 1884. 



eartliquakes which are seen to be in the north and south components of 

 motion, their periods in seconds are as follows : — 



Periods in Seconds 



The maximum amplitudes or half semi-oscillation in millimeters 

 measured in the north and south components, are as follows : — 



Amplitudes in Millimeters 



On the assumption of harmonic motion the maximum velocities in 

 millimeters per second calculated from the above periods and amplitudes 

 are as follows : — 



Maximum Velocities in Millimeters per second 



The maximum acceleration in millimeters per second calculated from 

 the maximum velocities and amplitudes, is as follows : — 



Maximum Acceleration in Millimeters per second 



