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hundreds of kilometers from the nearest active fault, gerland promoted a
vision of seismology in which the earth figured more as a distant planet
than as the home of intelligent life.
Across the Surface of the Globe
the most notable absence at the iSA's 1901 meeting, next to Milne's, was
that of Montessus de Ballore. it was Montessus who later pinpointed what
was so controversial about the fledgling iSA: “if the seismographs register
every slightly intense earthquake, wherever it is produced, there follows the
unexpected consequence that, at least theoretically, a single seismological
observatory would suffice to observe them all from a single point on the
earth's surface. that is perhaps what the countries that abstained from the
Strasbourg conference said to themselves.”
27
the fear was not just that ger-
many's rivals would be cut out of seismological research, but that seismology
itself would be transformed: that its diverse modes of investigation—geo-
logical, statistical, historical, and geophysical—would be reduced solely to
the instrumental registration of remote events. Montessus appreciated the
potential of seismographic research, but he feared an overreliance on it.
to cast doubt on gerland's project, he drew freely on geology's romantic,
heroic image of empirical field research.
28
there was a risk of overdrawing
this caricature. As Stephen Jay gould once noted, geologists have tended
to paint the history of their field in black and white. hutton figures as the
honest empiricist, Werner as the proto-lab scientist. Yet gerland's critics
took a more nuanced stance, acknowledging the complementarity of new
instrumental techniques and field-based experience.
Montessus also pointed out the artificiality of gerland's contrast be-
tween the “new” seismology and the “old.” gerland implied that these
fields could be distinguished in part by their objects of study: “microseisms”
versus “macroseisms.” Microseisms were, by definition, imperceptible to
humans and of uncertain origin, but they could hold clues to the nature of
the planetary mass through which they traveled. Montessus objected: “the
distinction between macroseisms and microseisms is artificial in the sense
that it depends on the individual acuity of the senses of the different observ-
ers.” Moreover, microseisms might be due to any of a potentially infinite
array of causes. As Montessus attempted to enumerate them, these included
“winds, tides, solar heat, barometric pressure, ocean currents, snow accu-
mulation, avalanches, rockslides, movements of railway cars, explosions of
mines, volcanic phenomena, etc., etc.”
29
the category of microseism also in-
cluded waves from strong earthquakes, which would register with small am-
