"Yes, I might," interrupted Dr. Jim sarcastically, "if I were acquainted with secret writing. But this is Dutch to me and worse, for I have some knowledge of Dutch and absolutely none of this. Let us try your "E" idea Stephen, and see what we make of it. The Chinese paper cipher is the shortest. We will count the letter that is most frequent, and call it 'E.' Something may come of the attempt." Herrick counted and Stephen checked his reckoning. "Four 'D's,'" said Jim. "Five 'K's.' Three 'Z's:' and Three 'R's.'. Humph! Seems to me that 'K' is the predominating letter, and once it comes 'K.K' which might stand for double 'E.' Well we'll call it 'E.'" "But here are two 'R's' together," said Stephen. "That might stand also for double 'E.'" "Yes! But you forget that there are five 'K's' to three 'R's.' We agreed to call the letter which predominated 'E.'" "All right. Fire away, and see what you make of it." For the next hour the two men with pencil and paper, did their best to extort sense from the jumble of letters on this basis. At the end of the time they were both out of temper, and had not succeeded in obtaining even one reasonable word. "Hang it!" said Stephen throwing his paper to the other end of the carriage. "I don't believe it makes sense at all!" "Nonsense," replied Herrick wiping his face, "it is sure to make sense. All ciphers do. And I daresay this is an easy one. The easiest are usually the most difficult to unravel. That is an epigram Stephen." Stephen had taken up the paper again and was studying the cipher. "Fifteen I.T.K.X." he said musingly, "the figures and the letters run together here." "So they do in the Telegraph cipher," said Herrick, and read out, "Fifteen N.b.s.n.a.d.q. What of that?" "I thought it might be a date," said Marsh-Carr apologetically. Dr. Jim laughed. "It might--on the other hand it might not." "You forget the figures are concealed the same as the letters," said Stephen. "How do we know that," retorted the doctor. "Fifteen may be the key to the cipher. You may count one, or count five: or add the two together and count six: or subtract the two and count four. Then again you may have to count from left to right or right to left. And after all the cipher may be in Spanish, or English or in the Indian tongue for the matter of that; Carr was mixed up with the South American Indians you know. We'll never discover it Stephen. But I tell you what," added Jim struck with a sudden thought, "this Mexican devil may know what it means!" "In that case he must have put it in the paper," said Stephen, "he knew Carr and the cipher was used by Carr. What is more likely----" Herrick frowned. "There is some conspiracy on," he muttered. "I do not see what it all means. We must learn what these ciphers mean Stephen. It is a serious matter. Do you think the key might be found amongst your uncle's papers?" "He left no papers," replied Stephen, "I have looked."