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177
The Story of Alchemy and the Beginnings of Chemistry
·
M. M. Pattison Muir
163
The
chemist
does
not
call
these
substances
elements
because
he
has
been
forced
to
regard
the
minute
particles
of
them
as
undivided,
much
less
because
he
thinks
of
these
particles
as
indivisible;
his
mental
picture
of
their
structure
as
an
atomic
structure
formed
itself
from
the
fact
that
they
had
not
been
decomposed.
The
formation
of
the
class
element
followed
necessarily
from
observed
facts,
and
has
been
justified
by
the
usefulness
of
it
as
an
instrument
for
forwarding
accurate
knowledge.
The
conception
of
the
elementary
atom
as
a
particle
which
had
not
been
decomposed
followed
from
many
observed
facts
besides
those
concerning
elements,
and
has
been
justified
by
the
usefulness
of
it
as
an
instrument
for
forwarding
accurate
knowledge.
Investigations
proved
radio-activity
to
be
a
property
of
the
very
minute
particles
of
certain
substances,
and
each
radio-active
substance
to
have
characteristic
properties,
among
which
were
certain
of
those
that
belong
to
elements,
and
to
some
extent
are
characteristic
of
elements.
Evidently,
the
simplest
way
for
a
chemist
to
think
about
radio-activity
was
to
think
of
it
as
an
atomic
property;
hence,
as
atomic
properties
had
always
been
regarded,
in
the
last
analysis,
as
properties
of
elements,
it
was
natural
to
place
the
radio-active
substances
in
the
class
elements,
provided
that
one
forgot
for
the
time
that
these
substances
have
not
the
class-mark
have-not-been-decomposed.
As
the
facts
of
radio-activity
led
to
the
conclusion
that
some
of
the
minute
particles
of
radio-active
substances
are
constantly
disintegrating,
and
as
these
substances
had
been
labelled
elements,
it
seemed
probable,
or
at
least
possible,
that
the
other
bodies
which
chemists
have
long
called
elements
are
not
true
elements,
but
are
merely
more
stable
collocations
of
particles
than
the
substances
which
are
classed
as
compounds.
As
compounds
can
be
changed
into
certain
other
compounds,
although
not
into
any
other
compounds,
a
way
seemed
to
be
opening
which
might
lead
to
the
transformation
of
some
elements
into
some
other
elements.
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