Here the reference probably intended is to the possibilities which their theory revealed for other than the mineral kingdoms, a theory the truth of which they believed themselves to have demonstrated by accomplishing metallic transmutation. In this connection, it should be noticed that the philosophical stone was generally considered a universal medicine--a medicine for metals and man, the latter, of course, by inference. The occasional presence of these possibilities in the minds of adepts, and the comprehensive nature of the Hermetic theory, fully explain the aberrations of mystical commentators, who have mistaken the side issues for the end in view, not altogether inexcusably, because the end in view sinks into complete unimportance when compared with the side issues, and all that is of value in alchemy for the modern student of occultism is comprised in these same possibilities, in the application of the Hermetic theory to the supreme subject, Man. It is impossible within the limits of a brief introduction to do justice to an illimitable subject, to the art of psychic transmutation, to the spiritual alchemistry, the principles of which are contained in the arcane theory of the adepts, and which principles are by no means dependent for their truth on the actuality of metallic transmutation, so I must confine myself to a few general observations. The admirable lesson which we may learn of the alchemists is the exaltation of things in virtue beyond the unassisted ability of Nature. Such exaltation is possible, according to the adepts, both within and without the metallic kingdom. Man and the animals are alike included by this comprehensive theory of development, and it is therefore conceivable that a few of the Hermetic symbolists taught in their secret and allegorical fashion the method of alchemical procedure when man was the subject, and revealed the miraculous results of this labour in the typewritten books which they bequeathed to posterity. That Henry Khunrath was in search of the transmutation of metals up to a certain point and period is, I think, very clearly indicated by his visit to Dr Dee. That the _Amphitheatrum Sapientiæ Æternæ_, which was published in 1609, treats of a spiritual alchemy, is, however, evidenced by the nature of its symbols and by the general tenor of the strange esoteric commentary on some of the Hebrew psalms. Those who worked in metals may, or may not, have failed; it is by no means a point of importance to the discriminating student of occultism; but they have left behind them a theory which is wholly true in its application to that one substance in Nature which we know to be capable of indefinite perfectibility, and the splendour and glory of the accomplished _Magnum Opus_, when the young King issues from the Everlasting East, from the land of the Morning and of Paradise, “Bearing the crescent moon upon his crest,”