t the present moment, however, we are in the
full tide of a set of opinions that tend to make us believe not {309}
only in the possibility, but in the actual occurrence of the
transmutation of metals. Observations made with regard to radium have
revolutionized all the scientific thinking in this matter. Radium has
apparently been demonstrated changing into helium, and so there is a
transmutation of metals. On the strength of this and certain other
recently investigated physical phenomena, there is a definite tendency
in the minds of many serious students of physics and chemistry to
consider that other metals possibly change into one another, and that
all that is needed is careful observation to discover it, for this
change is supposed to be going on around us all the time. Not very
long since, a professor of physical science at an important American
university suggested that it would be extremely interesting to take a
large specimen of lead ore, say several tons, and having removed from
it carefully all traces of silver that might be contained in it, put
it away for twenty years, and then see whether any further traces of
silver could be found. The idea that possibly lead occasionally
changes into silver by some slow chemical process is evidently
deep-seated in his mind. It would remind one of Newton's expression
some two centuries ago, that he had seen copper and gold ores
occurring together in specimens, and that he looked upon this as
evidence that copper in the course of time changes into gold. Certain
it is that lead ores constantly occur in connection with silver, or at
least that silver is found wherever lead is; that a corresponding
relationship between gold and copper has also been noted; and that
Newton's idea was not near so absurd, in the light of what we now
know, or still more, what we surmise on good scientific grounds, as
the nineteenth century scientists would have had us believe.

{310}

As I go over this manuscript for the last time just before going to
press, there comes the announcement that Sir William Ramsay has
probably solved the problem of the transmutation of metals. He has
shown apparently that lithium, when acted upon by radium emanations,
changes to some extent to copper. It is true that the change is only
in small quantities, and that there is no question as yet of any
commercial value to the process; but we all know that it is by such
small scientific announcements as this that the ente