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is ordinarily understood. We are not yet in position to correlate destructive
effects with instrumental data so as to establish an adequate measure of
intensity. though the importance of the factor of acceleration is recognized,
we have as yet no satisfactory definition of intensity, no formula express-
ing earthquake violence in terms of ground movement.”
177
they were not
alone in judging that instruments had yet to be accurately correlated with
felt reports. In 1915, C. F. Marvin had gone so far as to claim that “measure-
ment of the intensity of earthquake movements on the acceleration basis is
as yet chiefly a concept of the imagination of the seismologist” and reflected
“grave ignorance of the imperfections of the seismograph.”
178
ten years later
Richard Oldham still concurred: “For determining the acceleration and am-
plitude instrumental methods must be left out of count, as suitable instru-
ments are still rare, sparsely scattered, and practically never happen to be
where the records would be of use.”
179
this was the problem that Wood encouraged the young Charles Rich-
ter to take up: the determination of a mechanical equivalent of intensity.
Richter had arrived at the Seismological Laboratory in 1927 with a PhD
in theoretical physics. His thesis had dealt with the latest developments in
quantum mechanics. “I never took courses in geology in my student years,”
he later admitted. He reasoned that working under Wood would allow him
to remain in Pasadena and “keep in touch” with the physics community.
180
Richter was by all accounts an odd man—“introverted,” “awkward,” “un-
able to laugh at himself.” Unbeknownst to most colleagues, among whom
he seemed unable to make close friends, he was also a poet, womanizer,
and, by the 1930s, a nudist. His biographer concludes that he suffered from
Asperger's syndrome.
181
Richter was soon drawn into Wood's program for
exploiting felt reports, down to the detail of seeking “a better word than the
word 'furnishings' in the item 'moved small objects, furnishings.'”
182
At a
personal level, though, Richter was hardly an ideal candidate to help main-
tain Wood's cooperative network.
existing accounts of the development of the Richter scale take Richter's
perspective, rather than Wood's.
183
they suggest misleadingly that the goal
was an absolute geophysical measure. In a somewhat cryptic statement,
Richter later explained: “We needed something which would not be subject
to misinterpretation in terms of the size and importance of the events.”
this explanation only makes sense in light of the question that prompted
it: whether the purpose of the scale had been above all a “public” one. Rich-
ter continued: “And also in the process of working with the scale it devel-
oped, which we had already suspected, that the statistics on earthquakes in
