§ =101.= It does not seem unlikely that if it is possible to “degrade” elements, it may be possible to build them up. It has been suggested that it might be possible to obtain, in this way, gold from silver, since these two elements occur in the same column in the Periodic Table; but the suggestion still awaits experimental confirmation. The question arises, What would be the result if gold could be cheaply produced? That gold is a metal admirably adapted for many purposes, for which its scarcity prevents its use, must be admitted. But the financial chaos which would follow if it were to be cheaply obtained surpasses the ordinary imagination. It is a theme that ought to appeal to a novelist of exceptional imaginative power. However, we need not fear these results, for not only is radium extremely rare, far dearer than gold, and on account of its instability will never be obtained in large quantities, but, judging from the above-described experiments, if, indeed, the radium emanation is the true Philosopher’s Stone, the quantity of gold that may be hoped for by its aid is extremely small. The Significance of “Allotropy.” § =102.= A very suggestive argument for the transmutation of the metals was put forward by Professor Henry M. Howe, LL.D., in a paper entitled “Allotropy or Transmutation?” read before the British Association (Section B), Sheffield Meeting, 1910. Certain substances are known which, although differing in their physical properties very markedly, behave chemically as if they were one and the same element, giving rise to the same series of compounds. Such substances, of which we may mention diamond, graphite and charcoal (_e.g._, lampblack)--all of which are known chemically as “carbon”--or, to take another example, yellow phosphorus (a yellow, waxy, highly inflammable solid) and red phosphorus (a difficultly-inflammable, dark red substance, probably possessing a minutely crystalline structure), are, moreover, convertible one into the other.[127] It has been customary to refer to such substances as different forms or allotropic modifications of the same element, and not to regard them as being different elements. As Professor Howe says, “If after defining ‘elements’ as substances hitherto indivisible, and different elements as those which differ in at least some one property, and after asserting that the elements cannot be transmuted into each other, we are confronted with the change from diamond into lampblack, and with the facts, first, that each is clearly indivisible hitherto and hence an element, and, second, that they differ in every property, we try to escape in a circle by saying that they are not different elements because they do change into each other. In short, we limit the name ‘element’ to indivisible substances which cannot be transmuted into each other, and we define those which do transmute as _ipso facto_ one element, and then we say that the elements cannot be transmuted. Is not