Various / 2008-06-12 00:00:00

Under heat
and velocity of sound waves, Dr. Mott stated that Newton found by
calculating the exact relative density and elasticity of air that sound
should travel only 916 feet a second, while it was known to travel 1,120
feet a second.
Laplace, by a heat and cold theory, tried to account for the 174 feet, and
supposed that in the condensed portion of a sound wave heat was generated,
and in the rarefied portion cold was produced; the heat augmenting the
elasticity and therefore the sound waves, and the cold produced
neutralizing the heat, thus kept the atmosphere at a constant temperature.
Dr. Mott stated that when Newton first pointed out this discrepancy of 174
feet, the theory should have been dropped at once, and later on he showed
the consequences of Laplace's heat and cold theory.
The great argument of the evening, and the one to which he attached the
most importance, was that all scientists have spoken of the swift movement
of the tuning fork, while in fact it moved 25,000 times slower than the
hour hand of a clock and 300,000,000 times slower than any clock pendulum
ever constructed.
Since a pendulum cannot, according to the high authorities, produce
sonorous air waves on account of its slow movement, Dr. Mott asks some one
to enlighten him how a prong of a tuning fork going 300,000,000 times
slower could be able to produce them. He then showed that there was not
the slightest similarity between the theoretical sound waves and water
waves, and still they are spoken of as "precisely similar" and
"essentially identical," and "move in exactly the same way.
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