“This is a deep-laid plot,” he went on calmly, still holding Prescott, while I backed up against the door and cut off his wife; “but it is not so difficult to see it after all.  Your part was to destroy the eyesight of the old man, to make it necessary for him to call on his daughter.  Your wife’s part was to play the role of Mrs. Martin, whom he had not seen for years and could not see now.  She was to persuade him, with her filial affection, to make her the beneficiary of his will, to see that his money was kept readily convertible into cash.

“Then, when the old man was at last out of the way, you two could decamp with what you could realise before the real daughter, cut off somewhere across the continent, could hear of the death of her father.  It was an excellent scheme.  But Haswell’s plain, material newspaper advertisement was not so effective for your purposes, Prescott, as the more artistic ‘telepagram,’ as you call it.  Although you two got in first in answering the advertisement, it finally reached the right person after all.  You didn’t get away quickly enough.

“You were not expecting that the real daughter would see it and turn up so soon.  But she has.  She lives in California.  Mr. Haswell in his delirium has just told of receiving a telegram which I suppose you, Mrs. Prescott, read, destroyed, and acted upon.  It hurried your plans, but you were equal to the emergency.  Besides, possession is nine points in the law.  You tried the gas, making it look like a suicide.  Jane, in her excitement, spoiled that, and Dr. Burnham, knowing where I was, as it happened, was able to summon me immediately.  Circumstances have been against you from the first, Prescott.”

Craig was slowly twisting up the hand of the inventor, which he still held.  With his other hand he pulled a paper from his pocket.  It was the old envelope on which he had written upon the occasion of our first visit to Mr. Haswell when we had been so unceremoniously interrupted by the visit of Dr. Scott.

“I sat here yesterday by this bed,” continued Craig, motioning toward the chair he had occupied, as I remembered.  “Mr. Haswell was telling Dr. Scott something in an undertone.  I could not hear it.  But the old man grasped the doctor by the wrist to pull him closer to whisper to him.  The doctor’s hand was toward me and I noticed the peculiar markings of the veins.

“You perhaps are not acquainted with the fact, but the markings of the veins in the back of the hand are peculiar to each individual--as infallible, indestructible, and ineffaceable as finger prints or the shape of the ear.  It is a system invented and developed by Professor Tamassia of the University of Padua, Italy.  A superficial observer would say that all vein patterns were essentially similar, and many have said so, but Tamassia has found each to be characteristic and all subject to almost incredible diversities.  There are six general classes—­in this case before us, two large veins crossed by a few secondary veins forming a V with its base near the wrist.