"Because he has reached a higher stage in the science of murder. The symptoms of that poor Yorkshireman were the symptoms of arsenical poisoning; the symptoms of which you have told me to-day denote a vegetable poison. _That_ affords very vague diagnosis, and leaves no trace. That was the agent which enabled the Borgias to decimate Rome. It is older than classic Greece, and simple as _a b c_, and will remain so until the medical expert is a recognized officer of the law, the faithful guardian of the bed over which the suspected poisoner loiters--past-master of the science in which the murderer is rarely more than an experimentalist, and protected from all the hazards of plain speaking by the nature of his office." "Great Heaven, how am I to save her?" exclaimed Valentine. He could not contemplate the subject in its broad social aspect; he could only think of this one dear life at stake. "To send this Dr. Jedd might be to hasten her death; to send a less efficient man would be mere childishness. WHAT shall I do?" He looked despairingly at the surgeon, and in that one glance perceived what a frail reed this was upon which he was leaning. And then, like the sudden gleam of lightning, a name flashed across his mind,--George Sheldon, the lawyer, the schemer, the man who of all the world best knew this vile enemy and assassin against whom he was matched; he it was of whom counsel should be asked in this crisis. Once perceiving this, Valentine was prompt to act. It was the first flash of light in the darkness. "You mean to stand by me in this, don't you?" he asked Mr. Burkham. "With all my heart and soul." "Good. Then you must go to Dr. Jedd instantly. Tell him all you know--Tom Halliday's death; the symptoms of Charlotte's decline, as you have heard them from me--_everything_; and let him hold himself in readiness to start for Hastings directly he hears from or sees me. I am going to a man who of all men can tell me how to deal with Philip Sheldon. I shall try to be in Burlington Row in an hour from this time; but in any case you will wait there till I come. I suppose, in a desperate case like this, Dr. Jedd will put aside all less urgent work?" "No doubt of that." "I trust to you to secure his sympathy," said Valentine. He was in the darksome entrance-hall by this time. Mr. Burkham followed, and opened the door for him. "Have no fear of me," he said. "Good bye." The two men shook hands with a grip significant as masonic sign-manual. It meant on the one part hearty co-operation, on the other implicit confidence. In the next moment Valentine sprang into the cab. "King's Road--entrance to Gray's Inn, and drive like mad!" he shouted to the driver. The hansom rattled across the stones, dashed round corners, struck consternation to scudding children in pinafores, all but annihilated more than one perambulator, and in less than ten minutes after leaving Mr. Burkham's door, ground against the kerbstone before the little gate of Gray's Inn.