by the mystery of phosphorescence and its apparent unrelatedness
to every other source of light. He was to tell afterwards in his
reminiscences how he watched the fireflies drifting and glowing
among the dark trees in the garden of the villa under the warm
blue night sky of Italy; how he caught and kept them in cages,
dissected them, first studying the general anatomy of insects
very elaborately, and how he began to experiment with the effect
of various gases and varying temperature upon their light. Then
the chance present of a little scientific toy invented by Sir
William Crookes, a toy called the spinthariscope, on which radium
particles impinge upon sulphide of zinc and make it luminous,
induced him to associate the two sets of phenomena. It was a
happy association for his inquiries. It was a rare and fortunate
thing, too, that any one with the mathematical gift should have
been taken by these curiosities.
Section 8
And while the boy Holsten was mooning over his fireflies at
Fiesole, a certain professor of physics named Rufus was giving a
course of afternoon lectures upon Radium and Radio-Activity in
Edinburgh. They were lectures that had attracted a very
considerable amount of attention. He gave them in a small
lecture-theatre that had become more and more congested as his
course proceeded. At his concluding discussion it was crowded
right up to the ceiling at the back, and there people were
standing, standing without any sense of fatigue, so fascinating
did they find his suggestions. One youngster in particular, a
chuckle-headed, scrub-haired lad from the Highlands, sat hugging
his knee with great sand-red hands and drinking in every word,
eyes aglow, cheeks flushed, and ears burning.
'And so,' said the professor, 'we see that this Radium, which
seemed at first a fantastic exception, a mad inversion of all
that was most established and fundamental in the constitution of
matter, is really at one with the rest of the elements. It does
noticeably and forcibly what probably all the other elements are
doing with an imperceptible slowness. It is like the single
voice crying aloud that betrays the silent breathing multitude in
the darkness. Radium is an element that is breaking up and flying
to pieces. But perhaps all elements are doing that at less
perceptible rates. Uranium certainly is; thorium-the stuff of
this incandescent gas mantle-certainly is; actinium. I feel
that we are but beginning the list. And we know now that the
atom, that once we thought hard and impenetrable, and indivisible
and final and-lifeless-lifeless, is really a reservoir of
immense energy. That is the most wonderful thing about all this
work. A little while ago we thought of the atoms as we thought
of bricks, as solid building material, as substantial matter, as
unit masses of lifeless stuff, and behold! these bricks are
boxes, treasure boxes, boxes full of the intensest force. This
little bottle contains about a pint of uranium oxide; that is to
say, about fourteen ounces of the element uranium. It is worth
about a pound. And in this bottle, ladies and gentlemen, in the
atoms in this bottle there slumbers at least as much energy as we
could get by burning a hundred and sixty tons of coal. If at a
word, in one instant I could suddenly release that energy here
and now it would blow us and everything about us to fragments; if
I could turn it into the machinery that lights this city, it
could keep Edinburgh brightly lit for a week. But at present no
man knows, no man has an inkling of how this little lump of stuff
can be made to hasten the release of its store. It does release
it, as a burn trickles. Slowly the uranium changes into radium,
the radium changes into a gas called the radium emanation, and
that again to what we call radium A, and so the process goes on,
giving out energy at every stage, until at last we reach the last
stage of all, which is, so far as we can tell at present, lead.
But we cannot hasten it.'
'I take ye, man,' whispered the chuckle-headed lad, with his red
hands tightening like a vice upon his knee. 'I take ye, man. Go
on! Oh, go on!'
The professor went on after a little pause. 'Why is the change
gradual?' he asked. 'Why does only a minute fraction of the
radium disintegrate in any particular second? Why does it dole
itself out so slowly and so exactly? Why does not all the
uranium change to radium and all the radium change to the next
lowest thing at once? Why this decay by driblets; why not a decay
en masse?… Suppose presently we find it is possible to
quicken that decay?'
The chuckle-headed lad nodded rapidly. The wonderful inevitable
idea was coming. He drew his knee up towards his chin and swayed
in his seat with excitement. 'Why not?' he echoed, 'why not?'
The professor lifted his forefinger.
'Given that knowledge,' he said, 'mark what we should be able to
do! We should not only be able to use this uranium and thorium;
not only should we have a source of power so potent that a man
might carry in his hand the energy to light a city for a year,
fight a fleet of battleships, or drive one of our giant liners
across the Atlantic; but we should also have a clue that would
enable us at last to quicken the process of disintegration in all
the other elements, where decay is still so slow as to escape our
finest measurements. Every scrap of solid matter in the world
would become an available reservoir of concentrated force. Do
you realise, ladies and gentlemen, what these things would mean
for us?'
The scrub head nodded. 'Oh! go on. Go on.'
'It would mean a change in human conditions that I can only
compare to the discovery of fire, that first discovery that
lifted man above the brute. We stand to-day towards
radio-activity as our ancestor stood towards fire before he had
learnt to make it. He knew it then only as a strange thing
utterly beyond his control, a flare on the crest of the volcano,