2. We must now take up the second phase of our subject, the problem of
the origin of matter.
Before we knew anything of radioactivity we could have dismissed such a
subject briefly by quoting the law of the conservation of matter, which
says that matter can neither be created nor destroyed by any means known
to science. By our knowledge of radioactivity we can make our answer a
little more learned, a little less abrupt, but none the less
discouraging to the advocate of the development hypothesis. We can tell
how the elements of high atomic weight, such as uranium and thorium, are
constantly giving off particles and are thus by loss or decomposition
being changed over into other elements, such as radium, niton, polonium
and lead. But our new knowledge compels us ultimately to give the same
answer as before, namely, that _we still do not know how matter ever
could have originated_, except that "in the beginning" it was called
into existence by the fiat of Him whom we Christians worship as our God,
the Creator. Thus we reach the conception of the universe as that of a
great clock gradually running down, which is certainly the antithesis of
that picture so long held before us by the advocates of the development
theory.
Uranium is a rather rare element, though known for over a hundred years,
and has an atomic weight of 238.5. In decomposing it gives off first a
helium atom, weight 4; and after this action has been repeated three
times the substance left is radium, atomic weight about 226.4. Thus
radium is simply uranium after it has lost three helium atoms. Radium in
its disintegration gives off three kinds of particles, namely, helium
atoms (positively electrified), [Greek: b]-rays or electrons, and
[Greek: g]-rays, the latter being identical with the X-rays, and having
penetrating power sufficient to carry them through six inches of lead or
a foot of solid iron. The final stage in this process of disintegration
is the ordinary element lead, in which condition the atoms seem to have
reached relative stability. Whether or not our stock of lead, with our
other common elements that are not radioactive, was originally produced
by the disintegration of these other elements, is merely a matter of
conjecture. We know nothing at all about it.
The length of time it takes for half the atoms of an element to change
is called its "life" or period. The periods of most of the radioactive
substances have been calculated, that of uranium being very long. The
calculated period of radium is 2,500 years, while that of polonium is
only 202 days, and that of niton 5.6 days. These unquestioned facts,
together with the enormous amount of heat evolved by the disintegration
of these substances (that from radium being about 250,000 times the heat
evolved by the combustion of carbon), have thrown a great deal of doubt
upon the older estimates of the age of the earth.
The discussion of the details of these theories would be unprofitable.
But through the mists of all these conflicting theories and
probabilities two facts of tremendous importance for our modern world
emerge in clear relief, namely, that the grand law of the conservation
of matter still holds true, and hence that _the matter of our world must
have had an origin at some time in the past wholly different in degree
and different in kind from any process going on around us that we call a
natural process_. These elements of high atomic weight that break down
into others of lower atomic weight may be so rare because they have been
about all used up in this process. At any rate, so far from revealing
the origin of matter as a process now going on, these phenomena are an
objective demonstration that all matter is more or less unstable and
liable under some unknown but ever-acting force to lose some portion of
that fund of energy with which it seems to have been primarily endowed.
_Not the evolution of matter but the degeneration of matter_ is the
plain and unescapable lesson to be drawn from these facts. The varieties
of matter may change greatly, and one variety or one chemical element
may be transformed into another. But this transformation _is by loss and
not by gain_. It is degeneration and not upward evolution that is now
opened up before our astonished eyes by this peep into the ultimate
laboratories of nature; and he is surely a blind observer who cannot
read in these facts the grand truth that all this substance called
matter with which science deals in her manifold studies must at some
time in the past, I care not when, have been _called into existence in
some manner no longer operative_. The past eternity of matter, as well
as its progressive development from the simple to the complex, seems
manifestly out of consideration in view of the facts as we now know
them. There is no ambiguity in the evidence. So far as modern science
can throw light on the question, there must have been a real Creation of
the materials of which our world is composed, a Creation wholly
different both in kind and in degree from any process now going on.