With this, the apparition, which, like the others, had shown itself as a colored picture moving to and fro upon the darkened wall of the tablinum, vanished.  The voice of the great Macedonian sounded hollow and unearthly, but what he said had interested the emperor deeply and raised his spirits.

However, his wish to see more spirits had remained unsatisfied.  The magician, who remained upon his knees with uplifted hands while the apparitions were visible, declared that the forces he was obliged to employ in exercising his magic power over the spirits had exhausted him.  His fine, bearded face was deathly pale, and his tall form trembled and shook.  His assistants had silently disappeared.  They had kept themselves and their great scrolls concealed behind a curtain.  Serapion explained that they were his pupils, whose office it was to support his incantations by efficient formulas.

Caracalla dismissed him graciously, then turning to the assembled company, he gave with much affability a detailed account of the wonders he had seen and heard.

“A marvelous man, this Serapion,” he exclaimed to the high-priest Timotheus—­“a master in his art.  What he said before proceeding to the incantations is convincing, and explains much to me.  According to him, magic holds the same relation to religion as power to love, as the command to the request.  Power!  What magic effect it has in real life?  We have seen its influence upon the spirits, and who among the children of men can resist it?  To it I owe my greatest results, and hope to be still further indebted.  Even reluctant love must bow to it.”

He gave a self-satisfied laugh, and continued:  “As the pious worshiper of the gods can move the heavenly ones by prayer and sacrifice, so—­the wondrous man declared—­the magician can force them by means of his secret lore to do his will.  Therefore, he who knows and can call the gods and spirits by the right name, him they must obey, as the slave his master.  The sages who served the Pharaohs in the gray dawn of time succeeded in fathoming the mystery of these names given to the everlasting ones at their birth, and their wisdom has come down to him through the generations as a priceless secret.  But it is not sufficient to murmur the name to one’s self, or be able to write it down.  Every syllable has its special meaning like every member of the human frame.  It depends, too, on how it is pronounced and where the emphasis lies; and this true name, containing in itself the spiritual essence of the immortals, and the outward sign of their presence, is different again from the names by which they are known among men.