as thorndyke and i arrived at the main gateway of the temple and he swung round into the narrow lane, it was suddenly borne in on me that i had made no arrangements for the night. events had followed one another so continuously and each had been so engrossing that i had lost sight of what i may call my domestic affairs.

"we seem to be heading for your chambers, thorndyke," i ventured to remark. "it is a little late to think of it, but i have not yet settled where i am to put up to-night."

"my dear fellow," he replied, "you are going to put up in your own bedroom which has been waiting in readiness for you ever since you left it. polton went up and inspected it as soon as you arrived. i take it that you will consider my chambers yours until such time as you may join the benedictine majority and set up a home for yourself."

"that is very handsome of you," said i. "you didn't mention that the billet you offered was a resident appointment."

"rooms and commons included," said thorndyke; and when i protested that i should at least contribute to the costs of living he impatiently waved the suggestion away. we were still arguing the question when we reached our chambers—as i will now call them—and a diversion was occasioned by my taking the lamp from my pocket and placing it on the table.

"ah," my colleague remarked, "that is a little reminder. we will put it on the mantelpiece for polton to collect and you shall give me a full account of your further adventures in the wilds of kennington. that was a very odd affair. i have often wondered how it ended."

he drew our two arm-chairs up to the fire, put on some more coal, placed the tobacco jar on the table exactly equidistant from the two chairs, and settled himself with the air of a man who is anticipating an agreeable entertainment.

i filled my pipe, and, taking up the thread of the story where i had broken off on the last occasion, began to outline my later experiences. but he brought me up short.

"don't be sketchy, jervis. to be sketchy is to be vague. detail, my child, detail is the soul of induction. let us have all the facts. we can sort them out afterwards."

i began afresh in a vein of the extremest circumstantiality. with deliberate malice i loaded a prolix narrative with every triviality that a fairly retentive memory could rake out of the half-forgotten past. i cudgelled my brains for irrelevant incidents. i described with the minutest accuracy things that had not the faintest significance. i drew a vivid picture of the carriage inside and out; i painted a lifelike portrait of the horse, even going into particulars of the harness—which i was surprised to find that i had noticed. i described the furniture of the dining-room and the cobwebs that had hung from the ceiling; the auction-ticket on the chest of drawers, the rickety table and the melancholy chairs. i gave the number per minute of the patient's respirations and the exact quantity of coffee consumed on each occasion, with an exhaustive description of the cup from which it was taken; and i left no personal details unconsidered, from the patient's finger-nails to the roseate pimples on mr. weiss's nose.

but my tactics of studied prolixity were a complete failure. the attempt to fatigue thorndyke's brain with superabundant detail was like trying to surfeit a pelican with whitebait. he consumed it all with calm enjoyment and asked for more; and when, at last, i did really begin to think that i had bored him a little, he staggered me by reading over his notes and starting a brisk cross-examination to elicit fresh facts! and the most surprising thing of all was that when i had finished i seemed to know a great deal more about the case than i had ever known before.

"it was a very remarkable affair," he observed, when the cross-examination was over—leaving me somewhat in the condition of a cider-apple that has just been removed from a hydraulic press—"a very suspicious affair with a highly unsatisfactory end. i am not sure that i entirely agree with your police officer. nor do i fancy that some of my acquaintances at scotland yard would have agreed with him."

"do you think i ought to have taken any further measures?" i asked uneasily.

"no; i don't see how you could. you did all that was possible under the circumstances. you gave information, which is all that a private individual can do, especially if he is an overworked general practitioner. but still, an actual crime is the affair of every good citizen. i think we ought to take some action."

"you think there really was a crime, then?"

"what else can one think? what do you think about it yourself?"

"i don't like to think about it at all. the recollection of that corpse-like figure in that gloomy bedroom has haunted me ever since i left the house. what do you suppose has happened?"

thorndyke did not answer for a few seconds. at length he said gravely:

"i am afraid, jervis, that the answer to that question can be given in one word."

"murder?" i asked with a slight shudder.

he nodded, and we were both silent for a while.

"the probability," he resumed after a pause, "that mr. graves is alive at this moment seems to me infinitesimal. there was evidently a conspiracy to murder him, and the deliberate, persistent manner in which that object was being pursued points to a very strong and definite motive. then the tactics adopted point to considerable forethought and judgment. they are not the tactics of a fool or an ignoramus. we may criticize the closed carriage as a tactical mistake, calculated to arouse suspicion, but we have to weigh it against its alternative."

"what is that?"

"well, consider the circumstances. suppose weiss had called you in in the ordinary way. you would still have detected the use of poison. but now you could have located your man and made inquiries about him in the neighbourhood. you would probably have given the police a hint and they would almost certainly have taken action, as they would have had the means of identifying the parties. the result would have been fatal to weiss. the closed carriage invited suspicion, but it was a great safeguard. weiss's method's were not so unsound after all. he is a cautious man, but cunning and very persistent. and he could be bold on occasion. the use of the blinded carriage was a decidedly audacious proceeding. i should put him down as a gambler of a very discreet, courageous and resourceful type."

"which all leads to the probability that he has pursued his scheme and brought it to a successful issue."

"i am afraid it does. but—have you got your notes of the compass-bearings?"

"the book is in my overcoat pocket with the board. i will fetch them."

i went into the office, where our coats hung, and brought back the notebook with the little board to which it was still attached by the rubber band. thorndyke took them from me, and, opening the book, ran his eye quickly down one page after another. suddenly he glanced at the clock.

"it is a little late to begin," said he, "but these notes look rather alluring. i am inclined to plot them out at once. i fancy, from their appearance, that they will enable us to locate the house without much difficulty. but don't let me keep you up if you are tired. i can work them out by myself."

"you won't do anything of the kind," i exclaimed. "i am as keen on plotting them as you are, and, besides, i want to see how it is done. it seems to be a rather useful accomplishment."

"it is," said thorndyke. "in our work, the ability to make a rough but reliable sketch survey is often of great value. have you ever looked over these notes?"

"no. i put the book away when i came in and have never looked at it since."

"it is a quaint document. you seem to be rich in railway bridges in those parts, and the route was certainly none of the most direct, as you noticed at the time. however, we will plot it out and then we shall see exactly what it looks like and whither it leads us."

he retired to the laboratory and presently returned with a t-square, a military protractor, a pair of dividers and a large drawing-board on which was pinned a sheet of cartridge paper.

"now," said he, seating himself at the table with the board before him, "as to the method. you started from a known position and you arrived at a place the position of which is at present unknown. we shall fix the position of that spot by applying two factors, the distance that you travelled and the direction in which you were moving. the direction is given by the compass; and, as the horse seems to have kept up a remarkably even pace, we can take time as representing distance. you seem to have been travelling at about eight miles an hour, that is, roughly, a seventh of a mile in one minute. so if, on our chart, we take one inch as representing one minute, we shall be working with a scale of about seven inches to the mile."

"that doesn't sound very exact as to distance," i objected.

"it isn't. but that doesn't matter much. we have certain landmarks, such as these railway arches that you have noted, by which the actual distance can be settled after the route is plotted. you had better read out the entries, and, opposite each, write a number for reference, so that we need not confuse the chart by writing details on it. i shall start near the middle of the board, as neither you nor i seem to have the slightest notion what your general direction was."

i laid the open notebook before me and read out the first entry:

"'eight fifty-eight. west by south. start from home. horse thirteen hands.'"

"you turned round at once, i understand," said thorndyke, "so we draw no line in that direction. the next is—?"

"'eight fifty-eight minutes, thirty seconds, east by north'; and the next is 'eight fifty-nine, north-east.'"

"then you travelled east by north about a fifteenth of a mile and we shall put down half an inch on the chart. then you turned north-east. how long did you go on?"

"exactly a minute. the next entry is 'nine. west north-west.'"

"then you travelled about the seventh of a mile in a north-easterly direction and we draw a line an inch long at an angle of forty-five degrees to the right of the north and south line. from the end of that we carry a line at an angle of fifty-six and a quarter degrees to the left of the north and south line, and so on. the method is perfectly simple, you see."

"perfectly; i quite understand it now."

i went back to my chair and continued to read out the entries from the notebook while thorndyke laid off the lines of direction with the protractor, taking out the distances with the dividers from a scale of equal parts on the back of the instrument. as the work proceeded, i noticed, from time to time, a smile of quiet amusement spread over my colleague's keen, attentive face, and at each new reference to a railway bridge he chuckled softly.

"what, again!" he laughed, as i recorded the passage of the fifth or sixth bridge. "it's like a game of croquet. go on. what is the next?"

i went on reading out the notes until i came to the final one:

"'nine twenty-four. south-east. in covered way. stop. wooden gates closed.'"

thorndyke ruled off the last line, remarking: "then your covered way is on the south side of a street which bears north-east. so we complete our chart. just look at your route, jervis."

he held up the board with a quizzical smile and i stared in astonishment at the chart. the single line, which represented the route of the carriage, zigzagged in the most amazing manner, turning, re-turning and crossing itself repeatedly, evidently passing more than once down the same thoroughfares and terminating at a comparatively short distance from its commencement.

"why!" i exclaimed, the "rascal must have lived quite near to stillbury's house!"

thorndyke measured with the dividers the distance between the starting and arriving points of the route and took it off from the scale.

"five-eighths of a mile, roughly," he said. "you could have walked it in less than ten minutes. and now let us get out the ordnance map and see if we can give to each of those marvellously erratic lines 'a local habitation and a name.'"

he spread the map out on the table and placed our chart by its side.

"i think," said he, "you started from lower kennington lane?"

"yes, from this point," i replied, indicating the spot with a pencil.

"then," said thorndyke, "if we swing the chart round twenty degrees to correct the deviation of the compass, we can compare it with the ordnance map."

he set off with the protractor an angle of twenty degrees from the north and south line and turned the chart round to that extent. after closely scrutinizing the map and the chart and comparing the one with the other, he said:

"by mere inspection it seems fairly easy to identify the thoroughfares that correspond to the lines of the chart. take the part that is near your destination. at nine twenty-one you passed under a bridge, going westward. that would seem to be glasshouse street. then you turned south, apparently along the albert embankment, where you heard the tug's whistle. then you heard a passenger train start on your left; that would be vauxhall station. next you turned round due east and passed under a large railway bridge, which suggests the bridge that carries the station over upper kennington lane. if that is so, your house should be on the south side of upper kennington lane, some three hundred yards from the bridge. but we may as well test our inferences by one or two measurements."

"how can you do that if you don't know the exact scale of the chart?"

"i will show you," said thorndyke. "we shall establish the true scale and that will form part of the proof."

he rapidly constructed on the upper blank part of the paper, a proportional diagram consisting of two intersecting lines with a single cross-line.

"this long line," he explained, "is the distance from stillbury's house to the vauxhall railway bridge as it appears on the chart; the shorter cross-line is the same distance taken from the ordnance map. if our inference is correct and the chart is reasonably accurate, all the other distances will show a similar proportion. let us try some of them. take the distance from vauxhall bridge to the glasshouse street bridge."

the track chart, showing the route followed by weiss's carriage.

the track chart, showing the route followed by weiss's carriage.

a.—starting-point in lower kennington lane.

b.—position of mr. weiss's house. the dotted lines connecting the bridges indicate probable railway lines.

he made the two measurements carefully, and, as the point of the dividers came down almost precisely in the correct place on the diagram, he looked up at me.

"considering the roughness of the method by which the chart was made, i think that is pretty conclusive, though, if you look at the various arches that you passed under and see how nearly they appear to follow the position of the south-western railway line, you hardly need further proof. but i will take a few more proportional measurements for the satisfaction of proving the case by scientific methods before we proceed to verify our conclusions by a visit to the spot."

he took off one or two more distances, and on comparing them with the proportional distances on the ordnance map, found them in every case as nearly correct as could be expected.

"yes," said thorndyke, laying down the dividers, "i think we have narrowed down the locality of mr. weiss's house to a few yards in a known street. we shall get further help from your note of nine twenty-three thirty, when which records a patch of newly laid macadam extending up to the house."

"that new macadam will be pretty well smoothed down by now," i objected.

"not so very completely," answered thorndyke. "it is only a little over a month ago, and there has been very little wet weather since. it may be smooth, but it will be easily distinguishable from the old."

"and do i understand that you propose to go and explore the neighbourhood?"

"undoubtedly i do. that is to say, i intend to convert the locality of this house into a definite address; which, i think, will now be perfectly easy, unless we should have the bad luck to find more than one covered way. even then, the difficulty would be trifling."

"and when you have ascertained where mr. weiss lives? what then?"

"that will depend on circumstances. i think we shall probably call at scotland yard and have a little talk with our friend mr. superintendent miller; unless, for any reason, it seems better to look into the case ourselves."

"when is this voyage of exploration to take place?"

thorndyke considered this question, and, taking out his pocket-book, glanced through his engagements.

"it seems to me," he said, "that to-morrow is a fairly free day. we could take the morning without neglecting other business. i suggest that we start immediately after breakfast. how will that suit my learned friend?"

"my time is yours," i replied; "and if you choose to waste it on matters that don't concern you, that's your affair."

"then we will consider the arrangement to stand for to-morrow morning, or rather, for this morning, as i see that it is past twelve."

with this thorndyke gathered up the chart and instruments and we separated for the night.