“We ask,” says Mr. Crookes, “whether the chemical elements may not have been evolved from a few antecedent forms of matter—or possibly from only one such—just as it is now held that all the innumerable variations of plants and animals have been developed from fewer and earlier forms of organic life: built up, as Dr. Gladstone remarks, from one another according to some general plan. This building up, or evolution, is above all things not fortuitous: the variation and development which we recognise in the universe run along certain fixed lines which have been preconceived and foreordained. To the careless and hasty eye design and evolution seem antagonistic; the more careful inquirer sees that evolution, steadily proceeding along an ascending scale of excellence, is the strongest argument in favour of a preconceived plan.” Now, as in the organic world, so in the inorganic, it seems natural to view the chemical elements not as primordial, but as the gradual outcome of a process of development, possibly even of a struggle for existence. But this evolution of the elements must have taken place at a period so remote as to be difficult to grasp by the imagination, when our earth, or rather the matter of which it consists, was in a state very different from its present condition. The epoch of elemental development, remarks Mr. Crookes, is decidedly over, and it may be observed that in the opinion of not a few biologists the epoch of organic development is verging upon its close. Is there then, in the first place, any direct evidence of the transmutation of any supposed “element” of our existing list into another, or of its resolution into anything simpler? To this question Mr. Crookes answers in the negative. We find ourselves thus driven to indirect evidence—to that which we may glean from the mutual relations of the elementary bodies. First, we may consider the conclusion arrived at by Herschel, and pursued by Clerk-Maxwell, that atoms bear the impress of manufactured articles. “A manufactured article may well be supposed to involve a manufacturer. But it does something more: it implies certainly a raw material, and probably, though not certainly, the existence of by-products, residues, paraleipomena. What or where is here the raw material? Can we detect any form of matter which bears to the chemical elements a relation like that of a raw material to the finished product, like that, say, of coal-tar to alizarin? Or can we recognise any elementary bodies which seem like waste or refuse? Or are all the elements, according to the common view, co-equals? To these questions no direct answers are forthcoming.”