TO THE READER
The Basic Word List is different from any other selection of words designed to
make language-learning simple because it is a language in itself. It is not a first
stage (though it may be used as such) and it is certainly not a half-way home for
those whose interests are limited to tea-time talk and orders at a railway station.
With this pocket language it is possible to give an account of complex ideas and
delicate reactions to experience. Its solid structure may safely be used as a base for
the higher levels of Science.
At these higher levels, as was made clear in
Basic English Applied (Science),
short special lists are needed to take the
expert to the point at which language
becomes international, 100 words for
general science and 50 words for any one
branch of science make the necessary
bridge. As a simple example of
what might be done, Faraday's
Chemical
History of a Candle was put into Basic
with the help of the selection made by
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the Science Committee for chemistry
This is the first step in a design to get a
Basic Library of Science which will give
the greatest authorities an international
hearing.
But though these additions to Basic
are necessary when it is used by experts
writing for experts or would-be experts,
nothing but the 850 words of the general
list are needed in writing about science
at a simple level for a wider public. In
fact there is much to be said for the view
that this list is the best selection of words
for the purpose even in England and
America, because anyone limiting himself
on Basic lines will automatically put
things in a way which is clear to the general
reader -- if, that is, he himself has a good
knowledge of what he is writing about
At a time when public opinion may have
increasingly important effects on the
future of science, the general reader is a
person the experts would do well to take
more seriously ; and the current view that
any newspaper story is good enough for
the public may do great damage to the
cause of science. With the help of Basic,
science may be made simple without
becoming bad science.
8
This little book on astronomy will give
some idea of what it is possible to do
inside the narrowest Basic limits. Here
we have a straightforward account of the
stars in which (but for a small number of
international science words listed at the
end, and a small number of special words
whose sense is made clear in the account
itself or in footnotes) only the 850 general
Basic words are used.
Mr. Salzedo, one of our earliest and most
valued helpers, is a great authority on
languages, and has a knowledge of more
than 20 for purposes far wider than simply
talking. He first came before the Basic
public in a very different connection as
the writer of Basic for Business.
In these days one does not frequently
come across learning of so wide a range,
but the fact that he became expert at
Basic in something less than a day gives
one the key to his secret. It is not strange
that a man with such great powers of
attention has had time for so complex
a side-line as astronomy.
9
In the present book, Mr. Salzedo puts
forward his private views from time to
time, offering the reader a field for argument
and discussion; but for the most
part he wisely keeps to a statement of fact
and a record of observation. As such
account is surprisingly clear and simple-
so much so that his small son of twelve has
gone through every word with pleasure.
It is our belief that not only the Basic
learner, but all who are interested in
increasing their knowledge of the great
stage on which man is acting his small
part, will get profit from this book.
A complete list of the Basic books so
far printed is given on the last page.
C. K. Ogden.
The Orthological Institute
10, King's Parade, Cambridge, England
10
I . THE MOTIONS OF THE EARTH
Before the time of Copernicus, it seems that some of the Greeks in the old days
had the idea that it was the Earth, and not the different bodies seen in the sky,
which made the turning motion round the Sun every year, of which men had been conscious
for thousands of years.
So Copernicus was not the first to make that discovery that it is the Earth -- a great
ball in space, quite separate from all the other bodies, far and near, which are all
round it -- which, turning upon itself, makes our days, and, by moving round te Sun,
gives us our years.
But these are only the chief motions made by our Earth. There are quite a
number of others, which, though much
more complex than these, are now unquestioned. Some of these motions (there
are 13 of them) may be interesting to the
general reader, but others are much
11
harder to put before him in a clear and
simple way and, at the same time, will
probably have much less interest for him.
One of the most important of these
other motions has been given the long and
not very pleasing special name of the
" precession of the equinoxes." There is
no need for the reader to get this name
fixed in his memory, because its sense
will be clear to him from the account
given here :
Our year is the Sun-year, by which the
different times, summer and winter and
so on, are controlled.
But by watching the stars, we see that
there is no complete agreement between
the Sun-year and the motion of the stars.
The stars, for example the North Star, are
not back again in the same place at the
end of the sun-year. The distance they
are away from it is very small : about
50 seconds of angle (the sense of which
will be made clear later) every year. That
is the amount by which, when the Sun-year
is complete, we see that the North
Star is out of place. lt is caused by the
fact that the line going through the middle
of the Earth from north to south has a
motion as if it was writing small circles on
12
the sky, and this motion being in the
direction opposite to the motion round
the Sun we see that, after the Sun-year is
complete, the north point of the sky has
been moved back from its place of the
year before ; and it keeps on getting more
and more out of place every year.
The motion is like one of those play-things
which are whipped to make them
go round: when the motion is getting
slower, the top part seems to be rolling
from side to side while the point still keeps
in the same place.
It takes 25,868 years for one of these
circles of the Earth's north point among
the stars to be complete.
It is caused by the effect of the attraction
(a word about which we will have
more to say later) of the Sun and Moon
acting on the middle of the Earth, where
a sort of band of substance is formed
because the Earth is thicker there and
flatter at the poles.
The outcome of this motion is that when
a star map is made, in a short time it no
longer gives the true position of the stars
at a given time, and this fact has to be
taken into account in all lists of positions
of stars.
13
For this reason, what is now the North
Star (the greatest in the star-group of
Ursa Minor) will get nearer the true north
till the year 2105, but after that the north
of the Earth will be slowly moving away,
pointing from time to time to a different
star, and will not come back to our North
Star for over 25,000 years. It is interesting
to give a minute's thought to what will have
taken place on the Earth by that time.
Looking back 25,000 years to the last time
when the same star was the North Star,
we see that the nations which were in
existence at that time are all gone, and
there is almost no sign by which those
coming after might have any knowledge
of them, of their doings, desires, feelings ;
that is to say, of their existence. Will it
be the same with us in 25,000 years ?
Will all our hopes and high attempts, all
our loves and hates be covered over
completely by time, as if we had not
ever been ?
It would take up a great number of
pages to go into all the other motions of
the Earth. They are only important to
astronomers, and any attempt to give
the reader an account of them might put
an end to his interest. But there are two
motions so strange, so surprising in their
size and in their possible effects, that it
is only right to give them special attention.
14
The first of these is the motion, which has
been common knowledge for a long time,
by which the Sun, together with all its system,
goes through space roughly in the
direction of a star-group a great distance
away. That is the star-group Hercules,
which has no stars of the first size. As
the outcome of new measuring work done
with great care and on a number of stars,
the expert opinion now is that our Sun
with its family is going in the direction,
not quite of Hercules, but of a star-group
at its side, Lyra, and specially in the
direction of a point somewhere near the
very bright star of the first size in that
group, which is named Vega. The Earth
(with the Sun) is going in this direction
very quickly -- at about 16 miles a second.
This is almost as quick as the Earth's
motion round the Sun (about 18 miles a
second), but it is necessary to say here
that while this last motion and its rate
are certain, the motion in the direction of
Lyra is the outcome of such a number of
processes of measuring and mathematics
that there are a number of points at which
errors might be made, and for this reason
its direction and its rate are far from being
as certain as those of the other motions of
the Earth.
15
Such is the first of these two motions.
But the second is even more surprising.
Its discovery took place in 1926. Not
only our Sun with its planets, but all the
star system of which it is a part, is going
in the direction of a point in the star-group
of Capricorn, at a rate of about 200 miles
a second !
So we see that in place of being the
fixed base which to the first men on the
Earth it seemed so certainly to be, our
Earth has a great number of different
motions and is changing its position all
the time in a number of different ways ;
and, strangely enough, we are not conscious
with our senses at all of the two
motions which are among the greatest of
all: that which takes the Sun with the
Earth through space to some point in the
star group Lyra, and that other motion,
even greater, with which the star system,
of which our Sun is a part, is moving in
the direction of Capricorn. We only get
a knowledge of them by measuring with
great care the positions and motions of
the stars all round us.
16
It is a good thing for us that we have no
feeling of these motions. There is one
example only on record of any one having
truly seen one of them, when a man,
high up on a mountain, watching an
eclipsel of the Sun, saw the Moon's shade
at one time touching the far-off sky-line,
then 20 times as quickly as an airplane
go over all the country between and over
the sky-line on the other side. His feeling,
he says, was one of fear and a sense of
danger for which there are no words.
The same feeling was experienced in an
observation from an airplane in 1932.
17
II . HOW AND WHEN THE EARTH WAS FORMED
At one time the opinion was, so far as any thought was given to the question at
all, that the Sun was a great burning fire, and no one seemed to have any feeling of
surprise that it went on burning in this way for thousands of years without being used up.
But when chemistry came into existence it was quickly seen that this was not possible, that there is a limit to the time for
which an amount of substance, even if it
is as great as the Sun, is able to keep on
burning. Even if made completely of
coal, the Sun would have become so very
much smaller between the days of Julius
Caesar and now that there is great doubt
if it would be able to give out enough heat
to keep things living on the Earth. So
this idea had to be given up.
18
Another idea which was then put forward,
and which was given wide belief for
a long time, was this 1 mathematics makes
it clear that if a body like the Sun, while
in a heated condition, gets smaller in size,
its heat at the same time becomes greater ;
so the Sun got his heat by becoming
smaller. This view was current for
a long time, though it was hard to get
into agreement with the fact that the
Earth and the Sun have certainly been
in existence for hundreds of millions of
years, as may be seen by the stones of the
Earth, while the heat given off by the
effect of the Sun getting smaller would not
have been enough for 50 million years.
The general view at the present time
is that the heat of the Sun is caused
by the fact that the substance of which
the Sun is made is being broken up.
That is to say, that substance is being
changed into energy. In this way the
forces in the atom are being used to keep
up the Sun's heat and would give quite
enough energy to keep it going for all
the hundreds of millions of years which
would be needed for writing the record of
the stones and for hundreds of millions of
years to come.
19
As to the way in which the Earth and
the other moving stars of the Sun's system
came into existence, there have in the
same way been a number of views. The
view put forward by the great Frenchman
Laplace, and which for almost a hundred
years was judged to be true, was that there
had been a great mass of substance in the
form of a very thin gas of great heat,
stretching out much farther than the limit
of the Sun's system (which, in the time
of Laplace, was the planet Uranus, though
two planets at a greater distance from
the Sun than this have later come to
light, first Neptune, and, three years back,
Pluto). The idea was that this mass of
gas might have been caused by two older
stars coming together with great force
and being changed from hard, solid bodies
into thin gas of great heat, stretching out
into very wide space. This mass of gas
would go turning round, and its heat
would get greater when the force of
' attraction', which all material substances
have on one another, made it get smaller.
The turning motion became quicker and
quicker and the turning body smaller till
some ofthe substance came away, forming
rings round it. When time went on the
substance of these rings would come together
in the form of a ball. This process
20
at different times, it was said, gave us the
' planets,' of which the Earth is one. The
planets got colder and colder, harder and
harder, till, in the end, one of them at
least was able to give birth to living forms.
Such was the view of Laplace who died
in 1827. It was a very beautiful idea, and
was fully worked out by him with the help
of mathematics, on which he was a very
great authority. It was the current theory
for a very long time. It has now had to
be given up, because later authorities on
mathematics have made it clear that from
a mass of gas such as that of which we
have given an account no planets would
be formed, but only two stars near to one
another.
So it became necessary to have a look
round for some new way of accounting for
the birth and existence of the Earth and
the other planets.
The view which is now taken as to the
birth of the Sun's system (it gives no
account of the coming into existence of
the Sun itself) is based upon a very
common fact which is in the knowledge
of everybody. It is common knowledge
that the coming up and going down of the
waters of the seas, named ' tides', which
21
every one is able to take note of every day
at the seaside, are caused by the force of
attraction of the Sun and the Moon. The
waters, being free, are moved by this
attraction, and the tides go round the
Earth chiefly after the Moon, the Sun
having only a small part in causing this
motion. But there is another fact, which
only came to light a short time back,
and which is not common knowledge.
This fact, which will no doubt be a surprise
to some readers, is that the tides are not
limited to the seas, but that the solid face
of the Earth itself undergoes tide motions
in the form of a wave running round the
Earth, caused by the effect of the attraction
of the Moon. But this tide, though
naturally very much smaller than the tides
of the seas, is as much as 10 to 20 inches.
It is greatest at the middle of the Earth,
while it gets less in the north and south.
But though this Earth tide is so much
smaller than the tides of the sea, the
answer to our question, How did our
Earth come into separate existence? is
pointed out by this motion. We may
put it this way : The Moon is small, and
the effect of its attraction on the hard
Earth may be measured in inches. What
22
would take place if the Moon was a very
great body, and the Earth was a very great
body, as great as the Sun? The waves
caused in the solid outer part of the Earth
(which is very thin) by the attraction of
the great body so near it would be quite
high, so that a great amount of the substance
of the Earth would be pulled completely
away, and would not go back, but
keep out in space, in the form possibly of
a ring at first, the parts of which would
then little by little come nearer and nearer
together, till a ball was formed.
That is the current view about the way
in which the different great bodies forming
the Sun's system came into existence.
Thousands of millions of years back, when
what is now our Sun was a great body,
greater than now, and quite by itself,
another great body coming from outer
space, got nearer and nearer, till at last the
attraction of the new body on the Sun was
so strong that great masses of substance
were broken away, forming the Earth and
the other planets. On this view all such
bodies were formed at the same time and
out of the same great mass of substance
which had been broken away, because the
distances between the stars (which are in
fact suns) are so great that it would not
be possible that two of them would come
near to one another more than once even
in thousands of millions of years.
23
Such is the present view as to the way
in which the Sun and its system came into
existence. But it is only right to say here
that as the theory of Laplace was looked
upon as the right one for a hundred years,
and was seen to be wrong, so the new
theory, which is very much younger, may,
at some time in the future, be seen to be
no longer in agreement with the discoveries
which have then been made, and a new
theory will have to be formed which will
be in agreement with our new knowledge.
But if there are these great Earth-tides,
it is clear that Wells's very beautiful story
named " The Star " does not give a true
account of the events which would be the
outcome of the conditions pictured in it.
It says that a great, red body from outside
the Sun's system came near to the Earth,
and that the Earth was washed by great
tides of the seas at a great heat, causing
the destruction of all most all living things.
The true outcome would not be this, but
there would be great tides of the hard
24
Earth itself, by which earth-waves hundreds
of feet high would be caused. The
outer face of the Earth would be broken
through, great masses of liquid substance
at a great heat would come out and go
over all the Earth, or the Earth would
even be broken up into small bits.
We will have something to say later on
about the great space between Mars and
the greatest of all planets, Jupiter. In
this space there would normally be another
great planet, but in the place of it we see
hundreds of small ones. It may be that
here we have an example of the effect
caused on a planet by another great body
coming near to it. Millions of years back,
there may have been a great planet in
this space. Jupiter, with its great mass,
came near at some time, so near that
very high waves were caused on the
smaller planet, and it was broken up
into the hundreds of small bits we now
see.
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Last updated July 30, 2012.