Courtney Ryley Cooper - "The Cross Cut"

James Hay, Jr. - "The Winning Clue"

C. N. Williamson - "A Soldier of the Legion"

Daniel G. Brinton - "The Annals of the Cakchiquels"

Annual Bibliography of Commonwealth Literature 2007
This paper argues that discourses of love in Ghanaian market literature for youth offer a view into complex negotiations of agency and empowerment. Drawing on Deborah Durham's notion of youth as "social `shifters'" and Francis Nyamnjoh's conception of the "interconnectedness" of agency, I take Ghanaian market literature as one specific case of how African literature for youth foregrounds questions of continuity and change as African societies enter into increasingly complex global relations. In this literature for youth, received notions of love, often constructed out of impressions from American pop and hip hop music, carry new notions of agency that compete with existing "domesticated" forms. Authors like Ike Tandoh and Evelyn Tay employ discourses of love to offer youth alternative avenues for empowerment in a context of socio-economic disenfranchizement. In a creative process of "straddling", this writing both reveals and reproduces the contradictions that obtain in youth configurations of agency.

The Outline of Science, Vol. 1 (of 4)

J >> J. Arthur Thomson >> The Outline of Science, Vol. 1 (of 4)




However, the first step was to recognise that there were three distinct
and different rays that were given off by such metals as radium and
uranium. Sir Ernest Rutherford christened them, after the first three
letters of the Greek alphabet, the Alpha, the Beta, and Gamma rays. We
are concerned chiefly with the second group and purpose here to deal
with that group only.[3]

[3] The "Alpha rays" were presently recognised as atoms of helium
gas, shot out at the rate of 12,000 miles a second.

The "Gamma rays" are _waves_, like the X-rays, not material particles.
They appear to be a type of X-rays. They possess the remarkable power of
penetrating opaque substances; they will pass through a foot of solid
iron, for example.

The "Beta rays," as they were at first called, have proved to be one of
the most interesting discoveries that science ever made. They proved
what Crookes had surmised about the radiations he discovered in his
vacuum tube. But it was _not_ a fourth state of matter that had been
found, but a new _property_ of matter, a property common to all atoms of
matter. The Beta rays were later christened Electrons. They are
particles of disembodied electricity, here spontaneously liberated from
the atoms of matter: only when the electron was isolated from the atom
was it recognised for the first time as a separate entity. Electrons,
therefore, are a constituent of the atoms of matter, and we have
discovered that they can be released from the atom by a variety of
agencies. Electrons are to be found everywhere, forming part of every
atom.

"An electron," Sir William Bragg says, "can only maintain a separate
existence if it is travelling at an immense rate, from one
three-hundredth of the velocity of light upwards, that is to say, at
least 600 _miles a second, or thereabouts_. Otherwise the electron
sticks to the first atom it meets." These amazing particles may travel
with the enormous velocity of from 10,000 to more than 100,000 miles a
second. It was first learned that they are of an electrical nature,
because they are bent out of their normal path if a magnet is brought
near them. And this fact led to a further discovery: to one of those
sensational estimates which the general public is apt to believe to be
founded on the most abstruse speculations. The physicist set up a little
chemical screen for the "Beta rays" to hit, and he so arranged his tube
that only a narrow sheaf of the rays poured on to the screen. He then
drew this sheaf of rays out of its course with a magnet, and he
accurately measured the shift of the luminous spot on the screen where
the rays impinged on it. But when he knows the exact intensity of his
magnetic field--which he can control as he likes--and the amount of
deviation it causes, and the mass of the moving particles, he can tell
the speed of the moving particles which he thus diverts. These particles
were being hurled out of the atoms of radium, or from the negative pole
in a vacuum tube, at a speed which, in good conditions, reached nearly
the velocity of light, i.e. nearly 186,000 miles a second.

Their speed has, of course, been confirmed by numbers of experiments;
and another series of experiments enabled physicists to determine the
size of the particles. Only one of these need be described, to give the
reader an idea how men of science arrived at their more startling
results.

Fog, as most people know, is thick in our great cities because the
water-vapour gathers on the particles of dust and smoke that are in the
atmosphere. This fact was used as the basis of some beautiful
experiments. Artificial fogs were created in little glass tubes, by
introducing dust, in various proportions, for supersaturated vapour to
gather on. In the end it was possible to cause tiny drops of rain, each
with a particle of dust at its core, to fall upon a silver mirror and be
counted. It was a method of counting the quite invisible particles of
dust in the tube; and the method was now successfully applied to the new
rays. Yet another method was to direct a slender stream of the particles
upon a chemical screen. The screen glowed under the cannonade of
particles, and a powerful lens resolved the glow into distinct sparks,
which could be counted.

In short, a series of the most remarkable and beautiful experiments,
checked in all the great laboratories of the world, settled the nature
of these so-called rays. They were streams of particles more than a
thousand times smaller than the smallest known atom. The mass of each
particle is, according to the latest and finest measurements 1/1845 of
that of an atom of hydrogen. The physicist has not been able to find any
character except electricity in them, and the name "electrons" has been
generally adopted.


The Key to many Mysteries

The Electron is an atom, of disembodied electricity; it occupies an
exceedingly small volume, and its "mass" is entirely electrical. These
electrons are the key to half the mysteries of matter. Electrons in
rapid motion, as we shall see, explain what we mean by an "electric
current," not so long ago regarded as one of the most mysterious
manifestations in nature.

"What a wonder, then, have we here!" says Professor R. K. Duncan. "An
innocent-looking little pinch of salt and yet possessed of special
properties utterly beyond even the fanciful imaginings of men of past
time; for nowhere do we find in the records of thought even the hint of
the possibility of things which we now regard as established fact. This
pinch of salt projects from its surface bodies [i.e. electrons]
possessing the inconceivable velocity of over 100,000 miles a second, a
velocity sufficient to carry them, if unimpeded, five times around the
earth in a second, and possessing with this velocity, masses a thousand
times smaller than the smallest atom known to science. Furthermore,
they are charged with negative electricity; they pass straight through
bodies considered opaque with a sublime indifference to the properties
of the body, with the exception of its mere density; they cause bodies
which they strike to shine out in the dark; they affect a photographic
plate; they render the air a conductor of electricity; they cause clouds
in moist air; they cause chemical action and have a peculiar
physiological action. Who, to-day, shall predict the ultimate service to
humanity of the beta-rays from radium!"


Sec. 6

THE ELECTRON THEORY, OR THE NEW VIEW OF MATTER

The Structure of the Atom

There is general agreement amongst all chemists, physicists, and
mathematicians upon the conclusions which we have so far given. We know
that the atoms of matter are constantly--either spontaneously or under
stimulation--giving off electrons, or breaking up into electrons; and
they therefore contain electrons. Thus we have now complete proof of the
independent existence of atoms and also of electrons.

When, however, the man of science tries to tell us _how_ electrons
compose atoms, he passes from facts to speculation, and very difficult
speculation. Take the letter "o" as it is printed on this page. In a
little bubble of hydrogen gas no larger than that letter there are
_trillions_ of atoms; and they are not packed together, but are
circulating as freely as dancers in a ball-room. We are asking the
physicist to take one of these minute atoms and tell us how the still
smaller electrons are arranged in it. Naturally he can only make mental
pictures, guesses or hypotheses, which he tries to fit to the facts, and
discards when they will _not_ fit.

At present, after nearly twenty years of critical discussion, there are
two chief theories of the structure of the atom. At first Sir J. J.
Thomson imagined the electrons circulating in shells (like the layers of
an onion) round the nucleus of the atom. This did not suit, and Sir E.
Rutherford and others worked out a theory that the electrons circulated
round a nucleus rather like the planets of our solar system revolving
round the central sun. Is there a nucleus, then, round which the
electrons revolve? The electron, as we saw, is a disembodied atom of
electricity; we should say, of "negative" electricity. Let us picture
these electrons all moving round in orbits with great velocity. Now it
is suggested that there is a nucleus of "positive" electricity
attracting or pulling the revolving electrons to it, and so forming an
equilibrium, otherwise the electrons would fly off in all directions.
This nucleus has been recently named the proton. We have thus two
electricities in the atom: the positive = the nucleus; the negative =
the electron. Of recent years Dr. Langmuir has put out a theory that the
electrons do not _revolve round_ the nucleus, but remain in a state of
violent agitation of some sort at fixed distances from the nucleus.

[Illustration: PROFESSOR SIR J. J. THOMSON

Experimental discoverer of the electronic constitution of matter, in the
Cavendish Physical Laboratory, Cambridge. A great investigator, noted
for the imaginative range of his hypotheses and his fertility in
experimental devices.]

[Illustration: _From the Smithsonian Report_, 1915.

ELECTRONS PRODUCED BY PASSAGE OF X-RAYS THROUGH AIR

A photograph clearly showing that electrons are definite entities. As
electrons leave atoms they may traverse matter or pass through the air
in a straight path The illustration shows the tortuous path of electrons
resulting from collision with atoms.]

[Illustration: MAGNETIC DEFLECTION OF RADIUM RAYS

The radium rays are made to strike a screen, producing visible spots of
light. When a magnetic field is applied the rays are seen to be
deflected, as in the diagram. This can only happen if the rays carry an
electric charge, and it was by experiments of this kind that we obtained
our knowledge respecting the electric charges carried by radium rays.]

[Illustration: _Reproduced by permission of "Scientific American."_

PROFESSOR R. A. MILLIKAN'S APPARATUS FOR COUNTING ELECTRONS]

But we will confine ourselves here to the facts, and leave the
contending theories to scientific men. It is now pretty generally
accepted that an atom of matter consists of a number of electrons, or
charges of negative electricity, held together by a charge of positive
electricity. It is not disputed that these electrons are in a state of
violent motion or strain, and that therefore a vast energy is locked up
in the atoms of matter. To that we will return later. Here, rather, we
will notice another remarkable discovery which helps us to understand
the nature of matter.

A brilliant young man of science who was killed in the war, Mr. Moseley,
some years ago showed that, when the atoms of different substances are
arranged in order of their weight, _they are also arranged in the order
of increasing complexity of structure_. That is to say, the heavier the
atom, the more electrons it contains. There is a gradual building up of
atoms containing more and more electrons from the lightest atom to the
heaviest. Here it is enough to say that as he took element after
element, from the lightest (hydrogen) to the heaviest (uranium) he found
a strangely regular relation between them. If hydrogen were represented
by the figure one, helium by two, lithium three, and so on up to
uranium, then uranium should have the figure ninety-two. This makes it
probable that there are in nature ninety-two elements--we have found
eighty-seven--and that the number Mr. Moseley found is the number of
electrons in the atom of each element; that is to say, the number is
arranged in order of the atomic numbers of the various elements.


Sec. 7

The New View of Matter

Up to the point we have reached, then, we see what the new view of
Matter is. Every atom of matter, of whatever kind throughout the whole
universe, is built up of electrons in conjunction with a nucleus. From
the smallest atom of all--the atom of hydrogen--which consists of one
electron, rotating round a positively charged nucleus, to a heavy
complicated atom, such as the atom of gold, constituted of many
electrons and a complex nucleus, _we have only to do with positive and
negative units of electricity_. The electron and its nucleus are
particles of electricity. All Matter, therefore, is nothing but a
manifestation of electricity. The atoms of matter, as we saw, combine
and form molecules. Atoms and molecules are the bricks out of which
nature has built up everything; ourselves, the earth, the stars, the
whole universe.

But more than bricks are required to build a house. There are other
fundamental existences, such as the various forms of energy, which give
rise to several complex problems. And we have also to remember, that
there are more than eighty distinct elements, each with its own definite
type of atom. We shall deal with energy later. Meanwhile it remains to
be said that, although we have discovered a great deal about the
electron and the constitution of matter, and that while the physicists
of our own day seem to see a possibility of explaining positive and
negative electricity, the nature of them both is unknown. There exists
the theory that the particles of positive and negative electricity,
which make up the atoms of matter, are points or centres of disturbances
of some kind in a universal ether, and that all the various forms of
energy are, in some fundamental way, aspects of the same primary entity
which constitutes matter itself.

But the discovery of the property of radio-activity has raised many
other interesting questions, besides that which we have just dealt with.
In radio-active elements, such as uranium for example, the element is
breaking down; in what we call radio-activity we have a manifestation of
the spontaneous change of elements. What is really taking place is a
transmutation of one element into another, from a heavier to a lighter.
The element uranium spontaneously becomes radium, and radium passes
through a number of other stages until it, in turn, becomes lead. Each
descending element is of lighter atomic weight than its predecessor. The
changing process, of course, is a very slow one. It may be that all
matter is radio-active, or can be made so. This raises the question
whether all the matter in the universe may not undergo disintegration.

There is, however, another side of the question, which the discovery of
radio-activity has brought to light, and which has effected a revolution
in our views. We have seen that in radio-active substances the elements
are breaking down. Is there a process of building up at work? If the
more complicated atoms are breaking down into simpler forms, may there
not be a converse process--a building up from simpler elements to more
complicated elements? It is probably the case that both processes are at
work.

There are some eighty-odd chemical elements on the earth to-day: are
they all the outcome of an inorganic evolution, element giving rise to
element, going back and back to some primeval stuff from which they
were all originally derived infinitely long ago? Is there an evolution
in the inorganic world which may be going on, parallel to that of the
evolution of living things; or is organic evolution a continuation of
inorganic evolution? We have seen what evidence there is of this
inorganic evolution in the case of the stars. We cannot go deeply into
the matter here, nor has the time come for any direct statement that can
be based on the findings of modern investigation. Taking it altogether
the evidence is steadily accumulating, and there are authorities who
maintain that already the evidence of inorganic evolution is convincing
enough. The heavier atoms would appear to behave as though they were
evolved from the lighter. The more complex forms, it is supposed, have
_evolved_ from the simpler forms. Moseley's discovery, to which
reference has been made, points to the conclusion that the elements are
built up one from another.


Sec. 8

Other New Views

We may here refer to another new conception to which the discovery of
radio-activity has given rise. Lord Kelvin, who estimated the age of the
earth at twenty million years, reached this estimate by considering the
earth as a body which is gradually cooling down, "losing its primitive
heat, like a loaf taken from the oven, at a rate which could be
calculated, and that the heat radiated by the sun was due to
contraction." Uranium and radio-activity were not known to Kelvin, and
their discovery has upset both his arguments. Radio-active substances,
which are perpetually giving out heat, introduce an entirely new factor.
We cannot now assume that the earth is necessarily cooling down; it may
even, for all we know, be getting hotter. At the 1921 meeting of the
British Association, Professor Rayleigh stated that further knowledge
had extended the probable period during which there had been life on
this globe to about one thousand million years, and the total age of
the earth to some small multiple of that. The earth, he considers, is
not cooling, but "contains an internal source of heat from the
disintegration of uranium in the outer crust." On the whole the estimate
obtained would seem to be in agreement with the geological estimates.
The question, of course, cannot, in the present state of our knowledge,
be settled within fixed limits that meet with general agreement.

[Illustration: MAKING THE INVISIBLE VISIBLE

Radium, as explained in the text, emits rays--the "Alpha," the "Beta"
(electrons), and "Gamma" rays. The above illustration indicates the
method by which these invisible rays are made visible, and enables the
nature of the rays to be investigated. To the right of the diagram is
the instrument used, the Spinthariscope, making the impact of radium
rays visible on a screen.

The radium rays shoot out in all directions; those that fall on the
screen make it glow with points of light. These points of light are
observed by the magnifying lens.

A. Magnifying lens. B. A zinc sulphite screen. C. A needle on whose
point is placed a speck of radium.

The lower picture shows the screen and needle magnified.]

[Illustration: THE THEORY OF ELECTRONS

An atom of matter is composed of electrons. We picture an atom as a sort
of miniature solar system, the electrons (particles of negative
electricity) rotating round a central nucleus of positive electricity,
as described in the text. In the above pictorial representation of an
atom the whirling electrons are indicated in the outer ring. Electrons
move with incredible speed as they pass from one atom to another.]

[Illustration: ARRANGEMENTS OF ATOMS IN A DIAMOND

The above is a model (seen from two points of view) of the arrangement
of the atoms in a diamond. The arrangement is found by studying the
X-ray spectra of the diamond.]

As we have said, there are other fundamental existences which give rise
to more complex problems. The three great fundamental entities in the
physical universe are matter, ether, and energy; so far as we know,
outside these there is nothing. We have dealt with matter, there remain
ether and energy. We shall see that just as no particle of matter,
however small, may be created or destroyed, and just as there is no such
thing as empty space--ether pervades everything--so there is no such
thing as _rest_. Every particle that goes to make up our solid earth is
in a state of perpetual unremitting vibration; energy "is the universal
commodity on which all life depends." Separate and distinct as these
three fundamental entities--matter, ether, and energy--may appear, it
may be that, after all, they are only different and mysterious phases of
an essential "oneness" of the universe.


Sec. 9

The Future

Let us, in concluding this chapter, give just one illustration of the
way in which all this new knowledge may prove to be as valuable
practically as it is wonderful intellectually. We saw that electrons are
shot out of atoms at a speed that may approach 160,000 miles a second.
Sir Oliver Lodge has written recently that a seventieth of a grain of
radium discharges, at a speed a thousand times that of a rifle bullet,
thirty million electrons a second. Professor Le Bon has calculated that
it would take 1,340,000 barrels of powder to give a bullet the speed of
one of these electrons. He shows that the smallest French copper
coin--smaller than a farthing--contains an energy equal to eighty
million horsepower. A few pounds of matter contain more energy than we
could extract from millions of tons of coal. Even in the atoms of
hydrogen at a temperature which we could produce in an electric furnace
the electrons spin round at a rate of nearly a hundred trillion
revolutions a second!

Every man asks at once: "Will science ever tap this energy?" If it does,
no more smoke, no mining, no transit, no bulky fuel. The energy of an
atom is of course only liberated when an atom passes from one state to
another. The stored up energy is fortunately fast bound by the electrons
being held together as has been described. If it were not so "the earth
would explode and become a gaseous nebula"! It is believed that some day
we shall be able to release, harness, and utilise atomic energy. "I am
of opinion," says Sir William Bragg, "that atom energy will supply our
future need. A thousand years may pass before we can harness the atom,
or to-morrow might see us with the reins in our hands. That is the
peculiarity of Physics--research and 'accidental' discovery go hand in
hand." Half a brick contains as much energy as a small coal-field. The
difficulties are tremendous, but, as Sir Oliver Lodge reminds us, there
was just as much scepticism at one time about the utilisation of steam
or electricity. "Is it to be supposed," he asks, "that there can be no
fresh invention, that all the discoveries have been made?" More than one
man of science encourages us to hope. Here are some remarkable words
written by Professor Soddy, one of the highest authorities on
radio-active matter, in our chief scientific weekly (_Nature_, November
6, 1919):

The prospects of the successful accomplishment of artificial
transmutation brighten almost daily. The ancients seem to have had
something more than an inkling that the accomplishment of
transmutation would confer upon men powers hitherto the prerogative
of the gods. But now we know definitely that the material aspect of
transmutation would be of small importance in comparison with the
control over the inexhaustible stores of internal atomic energy to
which its successful accomplishment would inevitably lead. It has
become a problem, no longer redolent of the evil associations of the
age of alchemy, but one big with the promise of a veritable physical
renaissance of the whole world.

If that "promise" is ever realised, the economic and social face of the
world will be transformed.

Before passing on to the consideration of ether, light, and energy, let
us see what new light the discovery of the electron has thrown on the
nature and manipulation of electricity.


WHAT IS ELECTRICITY?

The Nature of Electricity

There is at least one manifestation in nature, and so late as twenty
years ago it seemed to be one of the most mysterious manifestations of
all, which has been in great measure explained by the new discoveries.
Already, at the beginning of this century, we spoke of our "age of
electricity," yet there were few things in nature about which we knew
less. The "electric current" rang our bells, drove our trains, lit our
rooms, but none knew what the current was. There was a vague idea that
it was a sort of fluid that flowed along copper wires as water flows in
a pipe. We now suppose that it is _a rapid movement of electrons from
atom to atom_ in the wire or wherever the current is.

Let us try to grasp the principle of the new view of electricity and see
how it applies to all the varied electrical phenomena in the world about
us. As we saw, the nucleus of an atom of matter consists of positive
electricity which holds together a number of electrons, or charges of
negative electricity.[4] This certainly tells us to some extent what
electricity is, and how it is related to matter, but it leaves us with
the usual difficulty about fundamental realities. But we now know that
electricity, like matter, is atomic in structure; a charge of
electricity is made up of a number of small units or charges of a
definite, constant amount. It has been suggested that the two kinds of
electricity, i.e. positive and negative, are right-handed and
left-handed vortices or whirlpools in ether, or rings in ether, but
there are very serious difficulties, and we leave this to the future.

[4] The words "positive" and "negative" electricity belong to the
days when it was regarded as a fluid. A body overcharged with the
fluid was called positive; an undercharged body was called negative.
A positively-electrified body is now one whose atoms have lost some
of their outlying electrons, so that the positive charge of
electricity predominates. The negatively-electrified body is one
with more than the normal number of electrons.

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