The Third R. Austin Freeman Megapack

by R. Austin Freeman

  “No, sir. What clockmakers call a snail is a flat disc with the edge cut out to a spiral shape, the shape of one of those flat water-snails. Resting against the edge of the snail by means of a projecting pin was a light steel bar with two pallets on it, and there was a seven-toothed star-wheel with long, thin teeth, one of which was always resting on the pallets. I may say that the whole movement excepting the day-wheel was driven by a separate little weight, so as to save the power of the clock.

  “And now let me explain how it worked. The day-wheel, driven by the clock, made a complete turn in twenty-four hours, and it carried the snail round with it. But as the snail turned, its spiral edge gradually pushed the pallet-bar away. A tooth of the star-wheel was resting on the upper pallet; but when the snail had nearly completed its turn, it had pushed the bar so far away that the tooth slipped off the upper pallet on to the lower one—which was quite close underneath. Then the snail turned a little more and the pin came to the end of the spiral—what we call ‘the step’—and slipped off, and the pallet-bar dropped back and let the tooth of the star-wheel slip off the lower pallet. Then the star-wheel began to turn until the next tooth was stopped by the upper pallet; and so it made a seventh of a turn, and, as it carried the two drums round with it, each of those made the seventh of a turn and changed the date in less than a second. Is that clear, sir?”

  “Quite clear,” replied Thorndyke (speaking for himself), “so far as the mechanism goes, but not so clear as to your deductions from it. I can see that this quite innocent calendar movement could be easily converted into a fire-raising appliance. But you seem to suggest that it was actually so converted. Have you any evidence that it was?”

  “I have, sir,” replied Polton. “What I have described is the calendar work just as I made it. There is no doubt about that, because when I took off the copper dial, there was the day-wheel with the snail on it still in place. Perhaps you noticed it.”

  “I did, but I thought it was part of some kind of striking-work.”

  “No, sir. The striking-work had been removed to make room for the calendar-work. Well, there was the day-wheel and the snail, and I have found the pallet-bar and the star-wheel and some of the other parts, so it is certain that the calendar movement was there. But there was something else. Somebody had made an addition to it, for I found another snail and another pallet-bar almost exactly like those of the calendar. But there was this difference: the day-snail had marked on it twelve lines, each denoting two hours; but this second snail had seven lines marked on it, and those seven lines couldn’t have meant anything but seven days.”

  “That is a reasonable assumption,” said Thorndyke.

  “I think, sir, that it is rather more than an assumption. If you remember that the star-wheel and the spindle that carried the two drums made one complete revolution in seven days, you will see that, if this snail had been fixed on to the spindle, it would also have made a revolution in seven days. But do you see what follows from that?”

  “I don’t,” said I, “so you may as well explain.”

  “Well, the day-snail turned once a day and, at the end of its turn, it suddenly let the pin drop into the step, released the star-wheel and changed the date in an instant. But this second snail would take a week to turn, and, at the end of the week, the pin would drop into the step, and in an instant some thing would happen. The question is, what was it that would have happened?”

  “Yes,” Thorndyke agreed, “that is the question, and first, can you think of any normal and innocent purpose that the snail might have served?”

  “No, sir. I have considered that question, and I can’t find any answer. It couldn’t have been any thing connected with the calendar, because the weeks aren’t shown on a calendar. There’s no need. When Sunday comes round, you know that it is a week since last Sunday; and no one wants to number the weeks.”

  “It is conceivable,” I suggested, “that someone might have had some reason for keeping count of the weeks, though it does seem unlikely. But could this addition be connected with the phases of the moon? They are sometimes shown on clocks.”

  “They are, usually, on these old clocks,” replied Polton, “but this movement would have been of no use for that purpose. The moon doesn’t jump from one phase to the next. It moves gradually; and the moon-disc on a clock shows the changes from day to day. Besides, this snail would have been unnecessary. A moon-disc could have been taken directly off the spindle and moved forward one tooth at each change of date. No, sir, I can think of no use for that snail but to do some particular thing at a given time on a given day. And that is precisely what I think it was made for.”

  I could see that Thorndyke was deeply impressed by this statement, and so was I. But there were one or two difficulties, and I proceeded to point them out.

  “You speak, Polton, of doing something at a given time on a given day. But your calendar gave no choice of time. It changed on the stroke of midnight. But this fire broke out at three o’clock in the morning.”

  “The calendar changed at midnight,” replied Polton, “because it was set to that time. But it could have been set to any other time. The snail was not fixed immovably on the pivot. It was held fast by a set-screw, but if you loosened the screw, you could turn the snail and set it to discharge at any time you pleased.”

  “And what about the other snail?” Thorndyke asked.

  “That was made in exactly the same way. It had a thick collet and a small set-screw. So you see, sir, the movement was easily controllable. Supposing you wanted it to discharge at three o’clock in the morning in five days’ time; first you set the hands of the clock to three hours after midnight, then you set the day-snail so that the step was just opposite the pin, and you set the week-snail so that the pin was five marks from the step. Then both the snails would be in the correct position by the day-wheel, and at three in the morning on the fifth day both snails would discharge together and whatever you had arranged to happen at that time would happen to the moment. And you notice, sir, that until it did happen, there would be nothing unusual to be seen or heard. To a stranger in the room, there would appear to be nothing but an ordinary grand father clock with a calendar—unless the little windows for the calendar had been stopped up, as I expect they had been.”

  Here Thorndyke anticipated a question that I had been about to put; for I had noticed that Polton had described the mechanism, but had not produced the parts for our inspection, excepting the carcase of the clock, which was on the bench.

  “I understand that you have the two snails and pallet-bars?

  “Yes, sir, and I can show them to you if you wish. But I have been making a model to show how the mechanism worked, and I thought it best for the purposes of evidence, to make it with the actual parts. It isn’t quite finished yet, but if you would like to see it—”

  “No,” replied Thorndyke, instantly realizing, with his invariable tact and sympathy, that Polton wished to spring his creation on us complete, “we will wait until the model is finished. But to what extent does it consist of the actual parts?”

  “As far as the calendar goes, sir, almost entirely. The day-wheel was on the clock-plate where you saw it. Then I found the snail and the spindle with the star-wheel still fixed to it. That is practically the whole of it excepting the wooden drums, which, of course, have gone.

  “As to the week-mechanism, I have got the snail and the pallet-bar only. There may not have been much else, as the week-snail could have been set on the spindle and would then have turned with the star-wheel.”

  “There would have had to be a second star-wheel, I suppose,” Thorndyke suggested.

  “Not necessarily, sir. If it was required for only a single discharge, a pivoted lever, or something that would drop right out when the pallet released it, would do. I have found one or two wheels that might have been used, but they may have come from the gramophone motors or the projectors, so one can’t be sure.”

  “Then,” said I, “you can’t sa
y exactly what the week-mechanism was like, or that your model will be a perfect reproduction of it?

  “No, sir,” he replied, regretfully. “But I don’t think that really matters. If I produce a model, made from the parts found in the ruins, that would be capable of starting a fire, that will dispose of the question of possibility.”

  “Yes,” said Thorndyke, “I think we must admit that. When will your model be ready for a demonstration?”

  “I can promise to have it ready by tomorrow evening,” was the reply.

  “And would you be willing that Inspector Blandy should be present at the demonstration?”

  The answer was most emphatically in the affirmative; and the gratified crinkle with which the permission was given suggested keen satisfaction at the chance of giving the inspector a shock.

  So the matter was left; and Thorndyke and I retired, leaving our ingenious friend to a despairing search among the rubbish for yet further traces of the sinister mechanism.

  CHAPTER XVI

  Polton Astonishes the Inspector

  Polton’s revelation gave us both a good deal of material for thought, and, naturally, thought generated discussion.

  “How does Polton’s discovery impress you?” I asked. “Is it a real one, do you think, or is it possible that he has only found a mare’s nest?”

  “We must wait until we have seen the model,” Thorndyke replied. “But I attach great weight to his opinions for several reasons.”

  “As, for instance—?”

  “Well, first there is Polton himself. He is a profound mechanician, with the true mechanician’s insight and imagination. He reads a certain function into the machine which he has mentally reconstructed, and he is probably right. Then there is the matter which we were discussing recently: the puzzling, contradictory nature of the case. We agreed that the whole group of events looks abnormal; that it suggests a connected group of events, intentionally brought about, with an unlawful purpose behind it, but there is not a particle of positive evidence connecting anyone with those events in the character of agent. The crux of the matter has been from the first the impossibility of connecting Haire with the outbreak of the fire. His alibi seemed to be unchallengeable; for not only was he far away, days before the fire broke out; not only, was there no trace of any fire-raising appliance; but the presence of the other man in the rooms seemed to exclude the possibility of any such appliance having been used.

  “But if Polton’s discovery turns out to be a real one, all these difficulties disappear. The impossible has become possible and even probable. It has become possible for Haire to have raised the fire while he was hundreds of miles away; and the appliance used was so ordinary in appearance that it would have passed unnoticed by the man who was living in the rooms. If Polton is right, he has supplied the missing link which brings the whole case together.”

  “You speak of probability,” I objected. “Aren’t you putting it too high? At the most, Polton can prove that the mechanism could have been used for fire-raising; but what is the evidence that it was actually so used?”

  “There is no direct evidence,” Thorndyke admitted. “But consider all the circumstances. The fire, itself, looked like the work of an incendiary, and all the other facts supported that view. The fatal objection was the apparent physical impossibility of the fire having been purposely raised. But Polton’s discovery—if we accept it provisionally—removes the impossibility. Here is a mechanism which could have been used to raise the fire, and for which no other use can be discovered. That, I say, establishes a probability that it was so used; and that probability would remain even if it could be proved that the mechanism had some legitimate function.”

  “Perhaps you are right,” said I. “At any rate, I think Blandy will agree with you. Is he coming to the demonstration?”

  “Yes. I notified him and invited him to come. I couldn’t do less; and, in fact, though I have no great love for the man, I respect his abilities. He will be here punctually at eight o’clock tonight.”

  In effect, the inspector was more than punctual, for he turned up, in a state of undisguised excitement, at half-past seven. I need not repeat his adulatory greeting of my colleague nor the latter’s disclaimer of any merit in the matter. But I noted that he appeared to be genuinely grateful for Thorndyke’s help and much more frank and open in his manner than he had usually been.

  As the demonstration had been arranged for eight, we occupied the interval by giving him a general outline of the mechanism while he fortified himself with a glass of sherry (which Thorndyke had, in some way, ascertained to be his particular weakness) and listened with intense attention. At eight o’clock, exactly, by Polton’s newly-completed regulator, the creator of that incomparable time-keeper appeared and announced that the model was ready for inspection, and we all, thereupon, followed him up to the laboratory floor.

  As we entered the big workroom, Blandy cast an inquisitive glance round at the appliances and apparatus that filled the shelves and occupied the benches; then he espied the model, and, approaching it, gazed at it with devouring attention.

  It was certainly an impressive object, and at the first glance I found it a little confusing, and not exactly what I had expected; but as the demonstration proceeded, these difficulties disappeared.

  “Before I start the movement,” Polton began, “I had better explain one or two things. This is a demonstration model, and it differs in some respects from the actual mechanism. That mechanism was attached to an eight-day clock, and it moved once in twenty-four hours. This one moves once in an abbreviated day of thirty seconds.”

  “Good gracious!” exclaimed Blandy. “How marvellous are the powers of the horologist! But I am glad that it is only a temporary arrangement. At that rate, we should all be old men in about twenty minutes.”

  “Well, sir,” said Polton, with an apologetic and crinkly smile, “you wouldn’t want to stand here for five days to see it work. But the calendar movement is exactly the same as that in Mr. Haire’s clock; in fact, it is made from the actual parts that I found in your box, excepting the two wooden drums and the ratchet pulley that carries the cord and weight. Those I had to supply; but the spindle that carries the drums, I found with the star-wheel on it.

  “As we haven’t got the clock, I have made a simple little clock to turn the snail, like those that are used to turn an equatorial telescope. You can ignore that. But the rest of the movement is driven by this little weight, just as the original was. Then, as to the addition that someone had made to the calendar, I have fixed the week-snail to the end of the spindle. I don’t suppose that is how it was done, but that doesn’t matter. This shows how the snail and pallet-bar worked, which is the important point.”

  “And what is that contraption in the bowl?” asked Blandy.

  “That,” Polton replied a little evasively, “you can disregard for the moment. It is a purely conjectural arrangement for starting the fire. I don’t suggest that it is like the one that was used. It is merely to demonstrate the possibility.”

  “Exactly,” said Blandy. “The possibility is the point that matters.”

  “Well,” Polton continued, “that is all that I need explain. I have fitted the little clock with a dial and one hand so that you can follow the time, and, of course, the day of the week and the day of the month are shown on the two drums. And now we can set it going. You see that the day-drum shows Sunday and the date-drum shows the first, and the hand on the dial shows just after three o’clock; so it has just turned three o’clock on Sunday morning. And, if you look at the week-snail, you will see that it is set to discharge on the fifth day—that is, at three o’clock on Friday morning. And now here goes.”

  He pulled up the little weight by its cord and released some sort of stop. Forthwith the little conical pendulum began to gyrate rapidly, and the single hand to travel round the dial, while Polton watched it ecstatically and chanted out the events as they occurred.

  “Six A.M., nine A.M., twelve no
on, three P.M., six P.M., nine P.M., midnight.”

  Here he paused with his eye on the dial, and we all watched expectantly as the hand moved swiftly towards the figure three. As it approached there was a soft click accompanied by a slight movement of the two drums. Then the hand reached the figure and there was another click; and, immediately, the two drums turned, and Sunday, the first, became Monday, the second.

  So the rather weird-looking machine went on. The little pendulum gyrated madly, the hand moved rapidly round the dial, and at each alternate three o’clock there came the soft click, and then the two drums moved together and showed a new day. Mean while, Polton continued to chant out his announcements—rather unnecessarily, as I thought, for the thing was obvious enough.

  “Tuesday, the third; Wednesday, the fourth; Thursday, the fifth, six A.M., nine A.M., noon, three P.M., six P.M., nine P.M., midnight—now, look out for Friday morning.”

  I think we were all as excited as he was, and we gazed at the dial with the most intense expectancy as the hand approached the figure, and the first warning click sounded. Then the hand reached the hour mark, and, immediately, there was a double click, followed by a faint whirring sound; and suddenly a cloud of white smoke shot up from the bowl and was instantly followed by a sheet of flame.

  “My word!” exclaimed Blandy, “there’s no nonsense about that. Would you mind showing us how that was done, Mr. Polton?”

  “It was quite a simple and crude affair,” Polton replied, apologetically, “but, you see, I am not a chemist.”

  “The simpler, the better,” said Blandy, “for it was quite effectual. I wish you had shown it to us before you let it off.”

  “That’s all right, sir,” said Polton. “I’ve got another ready to show you, but I thought I would like you to see how it worked before I gave you the details.”

  “Quite right, too, Polton,” said I. “The conjurer should always do the trick first, and not spoil the effect by giving the explanation in advance. But we want to see how it was done, now.”