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prospect of speaking without Faraday ’ s sympathetic ventriloquism. To fill the evening after
Wheatstone ’ s flight, Faraday described his own speculations about the nature of electric
and magnetic phenomena. His impromptu lecture was published as “ Thoughts on Ray
Vibrations, ” “ one of the most singular speculations that ever emanated from a scientific
mind, ” as John Tyndall put it.^42 As the story has come down, Wheatstone ’ s part has tended
to be portrayed as pitiable or even risible, his skittishness merely the embarrassing occa-
sion for Faraday ’ s profound discourse. In fact, Faraday began his own presentation by
giving an account of Wheatstone ’ s chronoscope, to which he said his further remarks
were “ incidental. ”
Wheatstone ’ s chronoscope was a descendant of his work in the years immediately fol-
lowing Faraday ’ s discovery of electromagnetic induction. In 1840, he published a “ Descrip-
tion of an Electro-Magnetic Clock, ” which accurately linked a master clock with several
slaves, “ enabling a single clock to indicate exactly the same time in as many different
places, distant from each other, as may be required. ”^43 To do this, Wheatstone used similar
techniques to those he employed for telegraphy, incorporating the master clock into
the telegraphic circuit using “ Faraday ’ s magneto-electric currents. ” Though Wheatstone
instances the use of these linked clocks in an astronomical observatory to synchronize
observations, he also notes that a modified form could be used “ to act at great distances. ”
Wheatstone ’ s electromagnetic clock was thus the first step in the large process of synchro-
nizing time throughout the world, so important for commercial and military purposes.^44
In 1844, Wheatstone extended this invention to allow automated measurements of baro-
metric pressure and temperature every half hour, controlled by his electromagnetic clock
and recorded automatically on paper.^45 His setup “ did not need any attention during an
entire week, during which it recorded 1,008 observations, ” one of the first completely
mechanized experiments. Though the emergent processes of industry had often relied on
prior scientific advances, now Wheatstone applied the automated techniques of industry
to science. In 1845, Wheatstone described his electromagnetic chronoscope, an extension
of his 1840 clock allowing measurements of very small times, such as the duration of
a bullet ’ s passage through a gun.^46 Wheatstone ’ s stopwatch was the direct precursor of
the Hipp chronoscope, which became the standard instrument for precise measurements
of duration.
Faraday was long aware of Wheatstone ’ s work in all these directions, especially his
results for the velocity of electricity, which seemed (perplexingly) larger than the velocity
of light. Yet both were finite speeds: both light and electricity took time to propagate, as
did sound.^47 The analogy with sound seemed to imply that electromagnetism and light
should also propagate through some kind of medium, the ether. Young had begun to discern
the problems with this imponderable substance, which Faraday now proposed to reject.^48
Speaking in 1846 in lieu of the missing Wheatstone, Faraday suggested that matter is
nothing “ but forces and the lines in which they are exerted ” and that light radiation is “ a
high species of vibration in the lines of force which are known to connect particles and