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Show WHAT IS AN ELEMENT? In his little book called "The Elements" Ele-ments" Sir William A. Tilden defines an element as "a substance from which by the operation of ordinary chemical processes only one kind ot matter can be obtained." This is something quite different from the four elements of Aristotle fire, water, wa-ter, earth and air or the salt, sulphur sul-phur and mercury of the alchemists. Even in modern times the conception of what an element really is has changed somewhat. Sir AYilliam adds: "Until quite recently the elements ele-ments of the inorganic world were supposed to be fixed, immutable with the lapse of ages or under the mighty forces concerned in the making of worlds. But within a few years we have learned that the atoms at least are continually crumbling away. It is impossible to say whether all may not be suffering a slow waste which in the long run may lead back to the primal chaos." |