"This drawing," replied Dr. Cairn, "was copied from the wall of a certain tomb--now reclosed. Since we knew that the tomb was that of one of the greatest wizards who ever lived in Egypt, we knew also that the inscription had some magical significance. We knew that the flowers represented here, were a species of the extinct sacred Lotus. All our researches did not avail us to discover for what purpose or by what means these flowers were cultivated. Nor could we determine the meaning of the cutting off,"--he ran his fingers over the sketch--"of the priestesses' hair by the high priest of the goddess--" "What goddess, sir?" "A goddess, Rob, of which Egyptology knows nothing!--a mystical religion the existence of which has been vaguely suspected by a living French _savant_ ... but this is no time--" Dr. Cairn closed the manuscript, replaced it and relocked the drawer. He glanced at the clock. "A quarter past one," he said. "Come, Rob!" Without hesitation, his son followed him from the house. The car was waiting, and shortly they were speeding through the deserted streets, back to the house where death in a strange guise was beckoning to Myra Duquesne. As the car started-- "Do you know," asked Dr. Cairn, "if Saunderson has bought any orchids--_quite_ recently, I mean?" "Yes," replied his son dully; "he bought a small parcel only a fortnight ago." "A fortnight!" cried Dr. Cairn excitedly--"you are sure of that? You mean that the purchase was made since Ferrara--" "Ceased to visit the house? Yes. Why!--it must have been the very day after!" Dr. Cairn clearly was labouring under tremendous excitement. "Where did he buy these orchids?" he asked, evenly. "From someone who came to the house--someone he had never dealt with before." The doctor, his hands resting upon his knees, was rapidly drumming with his fingers. "And--did he cultivate them?" "Two only proved successful. One is on the point of blooming--if it is not blooming already. He calls it the 'Mystery.'" At that, the doctor's excitement overcame him. Suddenly leaning out of the window, he shouted to the chauffeur: "Quicker! Quicker! Never mind risks. Keep on top speed!" "What is it, sir?" cried his son. "Heavens! what is it?" "Did you say that it might have bloomed, Rob?" "Myra"--Robert Cairn swallowed noisily--"told me three days ago that it was expected to bloom before the end of the week." "What is it like?" "A thing four feet high, with huge egg-shaped buds." "Merciful God grant that we are in time," whispered Dr. Cairn. "I could believe once more in the justice of Heaven, if the great knowledge of Sir Michael Ferrara should prove to be the weapon to destroy the fiend whom we raised!--he and I--may we be forgiven!"' Robert Cairn's excitement was dreadful. "Can you tell me nothing?" he cried. "What do you hope? What do you fear?" "Don't ask me, Rob," replied his father; "you will know within five minutes."