* * * * * NOTE TO NEW EDITION. A few small changes have been made. The last chapter has been re-written and considerably enlarged. M.M.P.M. FARNHAM, September 1913. * * * * * CONTENTS. CHAPTER I. THE EXPLANATION OF MATERIAL CHANGES GIVEN BY GREEK THINKERS II. A SKETCH OF ALCHEMICAL THEORY III. THE ALCHEMICAL NOTION OF THE UNITY AND SIMPLICITY OF NATURE IV. THE ALCHEMICAL ELEMENTS AND PRINCIPLES V. THE ALCHEMICAL ESSENCE VI. ALCHEMY AS AN EXPERIMENTAL ART VII. THE LANGUAGE OF ALCHEMY VIII. THE DEGENERACY OF ALCHEMY IX. PARACELSUS, AND SOME OTHER ALCHEMISTS X. SUMMARY OF THE ALCHEMICAL DOCTRINE--THE REPLACEMENT OF THE THREE PRINCIPLES OF THE ALCHEMISTS BY THE SINGLE PRINCIPLE OF PHLOGISTON XI. THE EXAMINATION OF THE PHENOMENA OF COMBUSTION XII. THE RECOGNITION OF CHEMICAL CHANGES AS THE INTERACTIONS OF DEFINITE SUBSTANCES XIII. THE CHEMICAL ELEMENTS CONTRASTED WITH THE ALCHEMICAL PRINCIPLES XIV. THE MODERN FORM OF THE ALCHEMICAL QUEST OF THE ONE THING INDEX LIST OF ILLUSTRATIONS FIG. AN ALCHEMICAL LABORATORY (Frontispiece) 1. THE MORTIFICATION OF METALS PRESENTED BY THE IMAGE OF A KING DEVOURING HIS SON 2 and 3. THE MORTIFICATION OF METALS PRESENTED BY IMAGES OF DEATH AND BURIAL 4 and 5. TWO MUST BE CONJOINED TO PRODUCE ONE 6. HERMETICALLY SEALING THE NECK OF A GLASS VESSEL 7. SEALING BY MEANS OF A MERCURY TRAP 8. AN ALCHEMICAL COMMON COLD STILL 9. A _BALNEUM MARIÆ_ 10. ALCHEMICAL DISTILLING APPARATUS 11. A PELICAN 12. AN ALCHEMIST WITH A RETORT 13. AN ALCHEMIST PREPARING OIL OF VITRIOL 14. ALCHEMICAL APPARATUS FOR RECTIFYING SPIRITS 15. PURIFYING GOLD PRESENTED BY THE IMAGE OF A SALAMANDER IN THE FIRE 16. PRIESTLEY'S APPARATUS FOR WORKING WITH GASES 17. APPARATUS USED BY LAVOISIER IN HIS EXPERIMENTS ON BURNING MERCURY IN AIR CHAPTER I THE EXPLANATION OF MATERIAL CHANGES GIVEN BY THE GREEK THINKERS. For thousands of years before men had any accurate and exact knowledge of the changes of material things, they had thought about these changes, regarded them as revelations of spiritual truths, built on them theories of things in heaven and earth (and a good many things in neither), and used them in manufactures, arts, and handicrafts, especially in one very curious manufacture wherein not the thousandth fragment of a grain of the finished article was ever produced. The accurate and systematic study of the changes which material things undergo is called chemistry; we may, perhaps, describe alchemy as the superficial, and what may be called subjective, examination of these changes, and the speculative systems, and imaginary arts and manufactures, founded on that examination.