Geoscience Reference
In-Depth Information
objects. Subjective here implied a physiological rather than psychological
bias. forel further distinguished between “
objective
observations, based on
the direction of swaying of a hanging object, or on the displaced of mobile
objects, and
subjective
observations, based on the simple appreciation of the
sensations of the observer.” Here, “subjective” did not imply unreliable.
It meant simply that the object under observation was the observer's own
body.
62
Critics of the use of lay observers often pointed to the difficulty of ex-
tracting precise reports of the time of an earthquake. The factor of time was
of the essence, necessary for determining whether separate reports related
to the same shock, calculating the velocity of the wave as it moved through
the earth's crust, and localizing the epicenter. In the moment of alarm, how-
ever, people rarely bothered to look at a clock. And if they did, it was all too
likely that the clock was wrong. With standardized time still a novelty, few
people could be relied on to calibrate their house clock or pocket watch to
the “telegraph” clock at the local railway station. At the start, forel was dis-
appointed to find that Switzerland's famed culture of precision timekeeping
fell short of scientific standards: “the setting of the clocks of towns, railways,
and telegraph stations leaves much to desire from the perspective of preci-
sion.”
63
Even thirty years later, in the case of the strong 1910 tremor in the
Berner Jura, Quervain was aghast to find that “among the many men of
science who encountered the earthquake fully awake, none saw fit to look
at his second hand and verify the setting of his watch.”
64
Again, the commis-
sion saw an opportunity for public enlightenment. They “aspired to educate
the public to be able to tell time with real precision.” In 1907 Quervain
published five hundred copies in German and french of an “Introduction
to Precise Timekeeping for observers.”
65
The point is that in Switzerland it
was not out of place for a scientist to berate the public to “to recognize the
moral duty, during an earthquake, first thing to look at the second hand.”
66
Already in 1881, “in the successive observations that are sent to us,” forel
observed “a progress and an improvement in the determination of time,
apparently the result of habituation and attention to the art of observing.”
67
In 1910 the commission remarked, “often it is complete amateurs who
distinguish themselves by a pleasing sense for precision.”
68
In addition to codifying a language of observation and developing meth-
ods for interpreting observation reports, forel presented a scheme for mov-
ing from discursive to quantitative description: a scale of seismic intensity,
measured according to “the simple observation of the effects produced
on man and his dwellings.”
69
The ten degrees of forel's scale ranged from
barely perceptible to disastrous, making it far more widely applicable than
