Geoscience Reference
In-Depth Information
ters (those bearing dates were all marked the second half of 1925, following
the Santa Barbara earthquake). One included a chart from the “Stormo-
graph barometer” at her mother's home in Santa Barbara, which had been
badly damaged in the earthquake. All her observations were made while
lying down, all but one at night. In one undated letter she wrote that she
had “not sent in the report of the last shake as I wanted to find out if you
wanted more than one person checking up on them, you undoubtedly feel
them all and note them down and basically mine are not necessary. I shall
be very glad however to continue if you wish me to.” Wood's response, from
29 October 1925, assured her: “While it is true, of course, that it would be
possible to have so many earthquake reports for a given region that their
use would be burdensome, in practice up to the present we have not had
enough. A moderate number of reports from independent observers in the
same small region usually present small differences which make them all
useful. So, if you do not find it burdensome, we shall be glad to have you
continue to send in reports on all occasions when you feel a shock, or learn
with details that one has been felt by others. With thanks for your interest
in this.”
166
this gracious response seems to have been typical of Wood's exchanges
with the public in these years. In other cases, he sought to demonstrate to
the observers the scientific value of their observations. In 1933 a resident
of Santa Catalina Island wrote Wood noting the elapsed time between the
radio announcement of the Long Beach earthquake and his own percep-
tion of it. Wood replied: “I thank you sincerely for your letter. . . . While of
course the time arrival determined [
sic
] by direct observation is somewhat
lacking in the degree of precision which we obtain from measurement on
our records it nevertheless will prove very useful to us and I may say at once
that it confirms roughly our latest estimates of distance from Pasadena and
neighboring stations.”
167
the following September a report arrived from a
man in Los Angeles whose wife and two neighbors had felt what he termed
an “earthquake” in scare quotes. Wood's note of thanks was dated two days
later and offered thoughtful comments: “If this was actually a natural shock
it must have been very small indeed. Our seismometers here register very
small disturbances, but there is no trace of any record at the time referred to.
A small artificial disturbance might be felt over a small area in your vicinity
and yet not be large enough to register in Pasadena.”
168
In 1933 the
BSSA
published a lengthy letter from a man who described visible surface waves;
Wood appended a discussion of the possible physical, physiological, and
psychological factors.
169
through such exchanges, Wood was paving a broad
avenue of communication with the public.