Lh MLLER 
| LateT| {Lt 
rey i br besk Ltt PRELIM 
Lee HET be dt ashe 
3 Ma i L} aul 
ory) | LETT | tT 
4 aan iLL ERT T [i 
en 
aa TERE | 04 j 
ITT if aaa | SECOND 
HERE Lest ttt EP PRELIM. 
Lite - TREMORS 
| | Ler ET r it 
nett | | 
of LEEFT | if HT 
tty 
iil [Lt | 
AEH eer H 
11:23 A.M.}tT | | 
APRIL 14, 7 
1907 EEE PTY ILLES By | Ir 
| 
aH) th 
LL LTT MAIN 
I WAVES 
4 = 
- Pt = 
Let 
Ati acaaiil! 
aa [ 
oll 2oaaeae 
ee: He —— 
ze =55 — 
Whee dati: 
lt ttt br 
L LTT 
LF | i 
[LEE TY 
Ltr] | 
lI 
SH) (|i 
Hl 
itt 
il 
pit T 
a is 
Hi 
TET 
EET] 
Fic. 1.—Record of the north-south component of the wave-motion rom the 
earthquake in Mexico of April 15, 1907, as registered on a Bosch-Omori horizontal 
pendulum at the U. S. Weather Bureau in Washington, D. C. (By courtesy of Pro- 
fessor C. F. Marvin.) The beginnings of the first and second preliminary tremors and 
of the main waves have been indicated. The intervals are minutes. 
