|
It must be really frustrating
to make a great scientific discovery, only to be ignored by everyone during
your lifetime. But that's just what happened to this hero, when in 1834 he
discovered a bizarre wave that no-one believed should exist.
Yet today it has given birth
to a whole new field of science. He was John Scott Russell. John Russell had
grown up in Glasgow where he was so fascinated by the great creak and roar
of the first Newcomen steam engines at the Carntyne mines, that he abandoned
his career in the church to become an engineer himself. He followed his
father's footsteps to St Andrews University, and then made such an
impression at Edinburgh University that he was appointed Prof. of Natural
Philosophy at just 24.
His first engineering success
was on the roads, where his fine vehicles were used to set up the Scottish
Steam Carriage Company in 1834, carrying 26 passengers between Glasgow and
Paisley. But within months his success was cut short - the hostile road
trustees sabotaged his carriage, causing a dreadful accident and killing
four of the passengers: perhaps the first fatal car crash? Not to be out
done, Russell accepted an invitation from the Union Canal Company to beat
off the challenge from the new steam carriages and railways by designing
better, faster boats - this was the turning point in his career. While
testing his boats on the Union Canal near Edinburgh, he decided that it was
the great bow wave the boats made that was slowing them down. As he rode
along the canal in August 1834, he watched a rapidly drawn boat as it
suddenly came to a halt in front of him. And something extraordinary
happened: The great hump of water built up in front of the boat kept on
moving as a single, huge wave, apparently without losing speed.
Russell set off on horseback
to follow this wave, and chased it for over a mile along the canal before it
started to weaken. This was no ordinary wave - Russell knew that Bernouilli
and Newton had described exactly how waves travel and disperse, but this one
didn't follow any of the rules, it just kept going. He was convinced he'd
seen something special and set out to discover what it was.
At his house in the New Town
district of Edinburgh he started 3 years of experiments on waves that would
become almost totally forgotten for a century. He supposed that the hump of
water in a bow wave in front of a boat should just drop into the water when
the boat stopped, but it doesn't. Russell carefully watched the behaviour of
many different waves: he called normal waves oscillatory waves, and his new
wave the Great Wave of Translation. He noticed that the wave of translation
did all sorts of strange things:
Its speed depends on the size
of the wave, and its width on the depth of water. And they're incredibly
stable: not only do they keep going for miles, but unlike normal waves
they'll never merge - so a small wave is overtaken by a large one, rather
than the two combining.
If a wave is too big for the
depth of water, it splits into two, one big and one small.
He realised that normal waves
tend to behave in two opposing ways: they either disperse and flatten out,
or steepen and topple over, depending on the depth of the water. The wave of
translation is so stable because these opposing tendencies are exactly
balanced, so cancel each other out. Russell wasn't just playing either. He
realised that the tides behaved just like his new wave, and reckoned he
could improve coastal defences and tidal rivers. Best of all, he worked out
how to make canal boats go faster. He'd been right about the bow wave
slowing canal boats down, but found out that by pulling the boat at just the
right speed it could rise up onto this wave of translation and surf
comfortably along with very little effort. On the strength of this he
introduced a new night sleeper canal service from Edinburgh to Glasgow, and
found that the horses could easily keep going if he kept the speed just
right. But despite his insistence that his discovery was important no-one
really wanted to know. People were just not prepared to accept any
contradiction to Newton and Bernoulli's theories of hydrodynamics.
So in 1844 Russell packed his
bags and set off for London. He made friends in high places, organised the
Royal Commission for the Great Exhibition of 1851, and made a great name as
a ship builder. But he was a better scientist than business man, and made
many enemies too - he was eventually ousted from the committee of the Great
Exhibition, and was thrown out of the Institute of Civil Engineers for some
dodgy arms deals during the American Civil War. He teamed up with Isambard
Kingdom Brunel to build the colossal Great Eastern steam ship, but fell out
with him dreadfully. Their continual petty arguing over finances and
responsibility for the ship eventually lead to Brunel's death as a broken
man.
Russell's business gradually
declined, and despite his earlier successes he too eventually died a
relatively poor man in 1882. It wasn't until the 1960's that scientists
realised just how important Russell's discovery had been. They reasoned that
if a wave in water could be made to travel so far, what about other waves,
like light? Today's most advanced fibre-optic communications use stable
pulses of light identical to Russell's waves, now called Solitons (from
solitary waves), to carry masses of information over thousands of kilometres
of fibres. So I'd like to remember John Scott Russell not as a once great
ship builder who fell on hard times, but as the grandfather of modern
telecommunications.
We'd like to thank Chris at
Heriot-Watt University for letting us copy this biography. See his site at
http://www.ma.hw.ac.uk/solitons/ where you can learn further information
on Scott Russell and his work. |
