Now you are asking the right kind of questions.
The distance between the Chile and the Rat Island earthquake was about 127 degrees
(everything is approximate here because data from the early 20th Century was still
only approximate). The time of the Rat Island event was 00:10:?? UT, that of the
Chile earthquake 00:40:?? UT. The time difference was approximately 30 minutes
give or take about a minute (somewhere between 29 and 31 minutes).
So given these basic facts, what can we say about far-field triggering.
A series of reflected s-waves arrive at 127 degrees from the Rat Island mainshock
beginning 28 minutes after the main event. Because these all arrive at about
the same time, they tend to concentrate seismic energy briefly at about 127-130
degrees for about two minutes. This situation is known as a cusp.
Because Chile lies at a cusp from the Rat Islands and the earthquake occurred
there within a minute or two of the arrival of this group of reflected S-waves,
it seems likely that the dynamic waves were the source of the triggering.

Following are the waves arriving from the Rat Islands in Chile and their travel
times:

SKKS 28min 0 sec
SKKKS 28 min 0 sec
SKS 26 min 18 sec
ScSP 30 min 14 sec
SkSP 30 min 49 sec
PS 30 min 50 sec

Can this type of information be used to actually forecast earthquakes? I think
there is some potential here. Look at the far-field forecast from the Kermadec
Island (Mw 7.2) earthquake of 3 June, a portion of which was posted to this board.
The predictor(s) who make these forecasts use a combination of cusp locations
and prior earthquake history to come up with these forecasts. I posted a mid-term
evaluation of that forecast earlier and will post a final evaluation later today.
The initial analysis suggests that this can be a useful tool in determining where
larger earthquakes will occur following large or great global quakes.