EARTHQUAKE MEASUlîEMEXTS IX PIT AND ON SURFACE. 2^7 



N. S. C'oiiipoiiont. 



(18.)— April 29tlu 1888.— A severe enrtlKHinke. Tliis i.. very 

 like the precedino- (^ne. liuf mur-li more intense. The beo-hinino- 

 portions of liotli sets of diagrams are given in D. XXXA^TT, Fig. 

 5. and Fig. G, The glass ]i]ate of tlie surface-ground instrument 

 made one revolution in 88 sec., .and tliat of tlie pit instrument in 

 70 sec. In tlie early ])art of the shock, the vibrations are very (juick, 

 and witli the exception (^f the wave marked A in the E. W. com- 

 p )n('nr llierc is no promincntiv lai'i^'c wave, ihoiigli ihc ripples :\vo 



