[127] Diamond is transformed into graphite when heated by a powerful electric current between carbon poles, and both diamond and graphite can be indirectly converted into charcoal. The artificial production of the diamond, however, is a more difficult process; but the late Professor Moissan succeeded in effecting it, so far as very small diamonds are concerned, by dissolving charcoal in molten iron or silver and allowing it to crystallise from the solution under high pressure. Graphite was also obtained. Red phosphorus is produced from yellow phosphorus by heating the latter in absence of air. The temperature 240-250° C. is the most suitable; at higher temperatures the reverse change sets in, red phosphorus being converted into yellow phosphorus.
“Is it philosophical to point to the fact that two such transmutable elements yield but a single line of derivatives as proof that they are one element? Is not this rather proof of the readiness, indeed irresistibleness, of their transmutation? Does not this simply mean that the derivativeless element, whenever it enters into combination, inevitably transmutes into its mate which has derivatives?”[128]
[128] Professor Henry M. Howe, LL.D.: “Allotropy or Transmutation.” (See The Chemical News, vol. cii. pp. 153 and 154, September 23, 1910.)
According to the atomic theory the differences between what are termed “allotropic modifications” are generally ascribed to differences in the number and arrangement of the atoms constituting the molecules of such “modifications,” and not to any differences in the atoms themselves. But we cannot argue that two such “allotropic modifications” or elements which are transmutable into one another are one and the same element, because they possess the same atomic weight, and different elements are distinguished by different atomic weights; for the reason that, in the determination of atomic weights, derivatives of such bodies are employed; hence, the value obtained is the atomic weight of the element which forms derivatives, from which that of its derivativeless mate may differ considerably for all we know to the contrary, if we do, indeed, regard the atomic weights of the elements as having any meaning beyond expressing the inertia-ratios in which they combine one with another.
If we wish to distinguish between two such “allotropic modifications” apart from any theoretical views concerning the nature and constitution of matter, we can say that such “modifications” are different because equal weights of them contain, or are equivalent to, different quantities of energy,[129] since the change of one “form” to another takes place only with the evolution or absorption (as the case may be) of heat.[130] But, according to modern views regarding the nature of matter, this is the sole fundamental difference between two different elements—such are different because equal weights of them contain or are equivalent to different quantities of energy. The so-called “allotropic modifications of an element,” therefore, are just as much different elements as any other different elements, and the change from one “modification” to another is a true transmutation of the elements; the only distinction being that what are called “allotropic modifications of the same element” differ only slightly in respect of the energy they contain, and hence are comparatively easy to convert one into the other, whereas different elements (so called) differ very greatly from one another in this respect, whence it is to be concluded that the transmutation of one such element into another will only be attained by the utilisation of energy in a very highly concentrated form, such as is evolved simultaneously with the spontaneous decomposition of the radium emanation.