Miriam wrenched her hand free. At last she understood--Corbin was a cocaine addict. For the first time she felt a twinge of fear as her glance swept the lonely countryside. Of all the demoralizing drugs, cocaine was the worst--whisky raised to its nth power was pap compared to it. "I have none, Corbin," she said, hiding her abhorrence of the man under a brusque manner. "We nurses are no longer permitted to keep a supply of narcotics on hand." "Doctor Roberts will let ye have a shot," eagerly. "Ye need never tell him it's for me." "Go to him yourself." Corbin stared at her for a long moment, his bloodshot eyes taking in her beauty appraisingly. The collar of her coat had turned back and he caught a glimpse of a gold chain. Martha had told him of rubies which she had seen around the nurse's neck. "I'll take care o' Roberts," he said thickly. "But me an' you are goin' to come to an understandin' right now. Hand over that gold chain. Ye won't!--then, by God--" Miriam had read the look in his eyes in time to spring aside and avoid his clutching fingers. Far more agile than her adversary, she eluded his attempt to trip her and, fear lending wings to her feet, she raced madly toward Abbott's Lodge. Corbin's heart hammered and thumped as he strove to overtake her. He was in no physical trim and, as Miriam left the footpath and took to the fields, he sank down by the roadside, panting from his exertions. As he rested his brain cleared and he cursed aloud as he realized the folly of his act. In his mad craving for cocaine he had betrayed his precious secret to Miriam. And she would tell. Corbin ground his teeth in rage, then his face cleared. Only Miriam knew--so far. When he got up and limped toward Abbott's Lodge, his lips wrinkled in a low and vicious smile. Finally convinced that she had outdistanced Corbin, Miriam dropped back to a walk. Considerably shaken by the fright he had given her, it took her some little time to stop looking over her shoulder to see if the caretaker was still following her. Then her thoughts switched around to Guy Trenholm and the bloodstained sheet, and her recent terror was forgotten. Had Corbin, by his evasive answers to the sheriff's question about the sheet, made Trenholm believe that she was implicated in Paul Abbott's murder? She recalled vividly his persistent questions at his bungalow that afternoon as to whether or not she had recognized Paul as the American soldier to whom her uncle had intrusted the Paltoff diamond. Could it be that Trenholm suspected her of having recognized Paul and seized the opportunity of being alone with her patient to kill him and recover the Paltoff diamond?