Page 112 - BBC History The Story of Science & Technology - 2017 UK

People & Personalities / Who invented...

Sections of the Space
Shuttle’s boosters travel to
Kennedy Space Centre

The flame in
Welsbach’s lamp
was surrounded
by a thorium
oxide mantle

What
connects…

the Space Who really
Shuttle with discovered… What connects…

a pair of radio? gas street lights

horses? The discovery of radio waves ranks
among the most astounding achieve-
ments of Victorian science, with with nuclear
The Space Shuttle’s solid far-reaching consequences that are
rocket boosters were manu- still felt today. power?
factured in Promontory, Utah. The existence of radio waves was
Transport to the launch site in predicted in the 1860s by the brilliant In 1885, Austrian scientist Carl Auer von
Florida, 3,860km (2,400 miles) Scottish theoretical physicist James Welsbach invented a new form of gas
away, involved a seven-day Clerk Maxwell (pictured above). He was lighting that was much brighter than
train journey. developing a theory proposing that earlier flame lamps.
electricity and magnetism are differ-
In order to fit through railway ent aspects of the same phenomenon. In the lamp introduced by von Welsbach,
tunnels along the route, each Maxwell’s prediction was confirmed in the flame was surrounded by a thorium
booster segment was 1887 by the German physicist Heinrich oxide mantle. Thorium oxide has a melting
designed to a maximum Hertz, who – incredibly – dismissed radio point of 3,300ºC. Von Welsbach’s mantle
diameter of just 3.66m (12ft). waves as “of no use whatsoever”. could therefore glow white-hot without
Fortunately, other scientists saw melting away.
The width of railway tunnels potential in the mysterious waves that
is determined by the gauge of could travel through air, solid walls and However, thorium is radioactive; it decays
the railway track. The US the vacuum of space. Among them were to radon-220, which is also radioactive.
uses the standard track the British physicist Oliver Lodge and the Using a thorium gas lamp isn’t danger-
gauge of 1.44m (4ft 8.5in). Italian electrical engineer Guglielmo ous, but old gas-mantle factory sites
Marconi, who independently invented suffer problems with contamination.
Early trains were drawn by ways of turning electrical discharges into
horses. The standard track detectable signals. The two men became Thorium is a safer alternative to uranium
gauge was based on the involved in several legal battles over or plutonium in nuclear reactors.
width of two horses pulling a patents, but Marconi is now usually Thorium can’t be weaponised, and its
cart side by side – a standard regarded as the ‘inventor’ of radio high melting point makes it less prone
that was retained when steam communication. That’s partly because to catastrophic meltdown.
railways were developed, so he was the first to send simple radio
that the same wagons could signals across the Atlantic Ocean –
be reused. a PR coup that brought him international
recognition including a Nobel Prize.
Yet even Marconi failed to realise the
full communication potential of radio. Marconi won the
Overcoming the technical challenges of
creating a high-fidelity speech-and- Nobel Prize, but even
music medium involved a host of far less
well-known inventors. he failed to realise the
full communication KEN KREMER/GETTY

potential of radio

112 The St
The Story of Science & Technologyory of Science & Technology