At the same time it was a point that would bear upon the final result. He kept it in mind. Other threads must now be taken up in turn, until the main current was reached which would sweep him on to the sea. He put away the document just received from Mrs. Leslie. While still looking at the other, some one sat down beside him. Darrell’s thoughts were fixed upon the subject which occupied his attention, and he did not even know there was some one in the next seat until a hand clutched his arm. “Where did you get that paper?” said a hoarse voice close by his ear. Turning his head at this he was surprised to see Paul Prescott beside him. Fortune plays some queer tricks at times, and this was one of them. What an odd chance that this man, of all in the great city, should sit down in the same car, at the very moment Darrell had that fatal paper in his hand. The circumstances were indeed so singular that Eric could not but start; but his excellent control over his nerves stood him in good stead again. He looked in the artist’s face—it was flushed and eager and angry—evidently he had not missed the letter up to now. “My dear sir, does it belong to you?” asked the detective, quietly. “It does, sir.” “Then take your property.” “Very good, sir; but I have a right to ask, yes, demand of you, to explain under what peculiar circumstances this document chanced to come into your possession.” “I do not question your right to ask that, and I shall readily tell where and when I picked the letter up.” So he gave the time and place to a dot, but did not say anything about having seen it drop from the pocket of the owner. Prescott remembered that this was when and where he had received the message, and he had no doubt of the truth of the story. At the same time he looked at the man by his side with a frown. “You read this?” he asked. “Naturally so—you could not blame me.” “And had your curiosity aroused?” “Well, yes, but that has nothing to do with it. Let us forget the circumstance.” “Willingly, since it concerns the private affairs of a very dear friend.” No more was said. Eric read his paper and the artist seemed occupied with his, but every now and then he turned his eyes toward the detective as though his curiosity was aroused. When the artist arose at Fourteenth Street, to leave the car, Eric handed him a card he had prepared for such occasions. It gave his name and the address of his apartments—nothing more. “If you should ever desire to see me, sir, you will find me there by letter or person,” he said quietly. At this Prescott smiled broadly. “I hope you don’t think I dream of sending you a challenge for finding my letter,” he said. “Well, you looked as black as a thunder cloud, and I didn’t know but what you might be meditating something of the sort.” “It was rude in me to act that way, and I beg your pardon for it.” Frankly said.