"The hour now arrives," he said, "when thou mayst pass the great but airy barrier,--when thou mayst gradually confront the terrible Dweller of the Threshold.

Continue thy labours--continue to surpass thine impatience for results until thou canst fathom the causes.

I leave thee for one month; if at the end of that period, when I return, the tasks set thee are completed, and thy mind prepared by contemplation and austere thought for the ordeal, I promise thee the ordeal shall commence.

One caution alone I give thee: regard it as a peremptory command, enter not this chamber!" (They were then standing in the room where their experiments had been chiefly made, and in which Glyndon, on the night he had sought the solitude of the mystic, had nearly fallen a victim to his intrusion.) "Enter not this chamber till my return; or, above all, if by any search for materials necessary to thy toils thou shouldst venture hither, forbear to light the naphtha in those vessels, and to open the vases on yonder shelves.

I leave the key of the room in thy keeping, in order to try thy abstinence and self-control.