ON SEISMOLOGICAL INVESTIGATION. 219 
A shock from Japan, No. 263, reached Victoria first, whilst two and 
four minutes later it reached Shide and Toronto. 
Illustrations of Seismograms. 
The following illustrations of seismograms are only to be regarded as 
sketches of the original photograms. They show the range of motion and 
principal characteristics of wave-groups, but they do not show details like 
small serrations clearly exhibited in the records from which they are 
derived. The numbers correspond with the numbers given for particular 
earthquakes in the preceding text. The arrow with its time-mark gives 
the time for a particular phase of movement, which is usually that of the 
commencement. The number following the letter S gives the time-scale 
in millimetres per hour. Thus S=60 means that 60 millimetres equal 
one hour. 
The locality at which a seismogram was obtained is indicated by the 
following initial or initials :— 
Isle of Wight . s + JW. Bombay : ‘ “eb: 
Kew F ' : K Calcutta 3 : 5G: 
Toronto F 2 be ale Batavia ae dies 
Victoria, B.C. . 4 HV. Mauritius 5 mya ils 
San Fernando . ‘ 5 ase t Potsdam : : a, Rs 
Madras . . $ . Mad. Philadelphia . ry peenestie 
8.21.1. 7.88.35. 
re $< 
~ rn 
No, 182.—ILW. S=59. No. 185.—IL.W. S=59°5. 
No. 182.—P. S=20. 
12.37 lve ’ 
v 
E— 
Ht 
No. 188.—I.W. S=59. No, 189.—LW. S=59°5. 
12.44.40. 7.48.0. 
No. 188.—T. S=58'25, No. 189.—P. S=20. 
No, 193.—I.W. S=59, 
No. 193.—T. S=585, 
