EartJiqitakcs in A'ctv' Mexico. — Bagg. 103 
eighth of ^larch at 12:26 a. m. The direction of tlie move- 
ment of the earth-wave during this shock was recorded by the 
writer's seismograph and was found to be an ahiiost true east 
and west movement, the motion being first toward the east 
and then to the west. Though the pendukim swung outward 
and back, making two complete vibrations, and returned to 
the centre, it is probable that there was but one vibration-wave 
instead of a double rocking motion. This is probable from the 
very fine wire used and the length of the pendulum whicli 
would of itself through momentum be carried out and back 
through the sand bed after the initial jar had passed. 
Upon investigation we find that there have been a number 
of earthquake shocks in this immediate vicinity at various 
intervals during the past and some have been quite violent. 
According to the most reliable evidence at hand from one of 
the oldest residents here there was a strong earthquake on the 
twenty-eighth of April, 1868, and again in April, 1869. This 
latter was the most serious known here. This earthquake shock 
affected the water flow in the Socorro springs at the base of 
Socorro mountain. Prior to this disturbance the water flowed 
most rapidlv from the southwest corner of the wet area about 
the springs. After the jar it shifted to the "north end of the 
water-bearing zone where it still issues forth in abundance, 
but not as strongly as it used to in the area farther south. Fur- 
thermore after this earthquake the w^ater became muddy and 
of a rusty color and remained so for many weeks. 
The next violent shock occurred on the sixth of July, 1886, 
when the County Commissioners were in session at the court 
house. There was a heavy rumbling sound preceding the jar 
and this was followed by so sharp a rocking of the building 
that the men endeavored to rush out of doors for safety. For- 
tunately the vibrations quickly passed and the building re- 
mained. 
Again in 1897 another earthquake was felt which is dis- 
tinctly remembered by many persons now residing here. This 
was sufficient in strength to overturn chairs and small ob- 
jects. One man crossing the plaza says that the ground 
seemed to roll towards him and he was forced to stop and sit 
down until the motion passed. 
