E.VIiTIigUAKi: MEASUKEMENT.S IX PIT AXD OX öUlil'ACE. 



21\ 



(17.)— Jaiiuarv Isl, 1S8D.— A small o:irlh(iiiakev 



(18.) — Fcl)riiary IStli, LSSÜ. — A severe eai'tli(|(iakr, in which 

 there was a considerahle aiiiouiit of vertical motion. The earlier 

 p(jrti<)ns of the cliagrains of the E. AV. component are given in PI. 

 XXXVII, Fig. 7. The glass plates of the surface and ])it instruments 

 made revolutions in 108 sec. and 95 sec. res])ectively. The periods 

 of the ^ibration are very short and the motion on the surface seems 

 to be much sharper than in the ])it. 



In this table ii^ nl .... are the number of irregular wavelets in 

 the successive 10 sec. intervals. 



