"Precisely," agreed the other, "and, as you'll note, that stop was evidently longer than either of the other two. They paid their fares, while Murphy's friends had to be relieved of two hundred and fifty dollars."
"From there on is what I'm interested in," announced Whitney. "What does the tape say?"
"It doesn't say anything," admitted the manager, with a smile. "But it indicates a whole lot. In fact, it blazes a blood-red trail that you ought to be able to follow with very little difficulty. See, when the machine started it kept on down Broadway—in fact, there's no sign of a turn for several blocks."
"How many?"
"That we can't tell—now. But we can figure it up very accurately later. The machine then turned to the right and went west for a short distance only—stopped for a few moments—and then went on, evidently toward the ferry, for here's a delay to get on board, here's a wavy line evidently made by the motion of the boat when the hand ought to have been practically at rest, and here's where they picked up the trip to Trenton. Evidently they didn't have to stop until they got there, because we have yards of tape before we reach a stop point, and then the paper is worn completely through by the action of the needle in oscillating, indicative of a long period of inaction. The return trip is just as plain."
"But," Whitney objected, "the whole thing hinges on where they went before going to Trenton. Murphy said they didn't have any bags, so they must have gone home or to some rendezvous to collect them. How are we going to find the corner where the machine turned?"
"By taking Murphy's car and driving it very carefully south on Broadway until the tape indicates precisely the distance marked on this one—the place where the turn was made. Then, driving down that street, the second distance shown on the tape will give you approximately the house you're looking for!"
"Good Lord," exclaimed Whitney, "that's applying science to it! Sherlock Holmes wasn't so smart, after all!"
Al and the manager agreed that there was too much traffic on Broadway in the daytime or early evening to attempt the experiment, but shortly after midnight, belated pedestrians might have wondered why a Green-and-White taxicab containing two men proceeded down Broadway at a snail's pace, while every now and then it stopped and one of the men got out to examine something inside.
"I think this is the corner," whispered the garage manager to Whitney, when they reached Eighth Street, "but to be sure, we'll go back and try it over again, driving at a normal pace. It's lucky that this is a new instrument and therefore very accurate."