“You can read a compass pretty quickly, I think?” Thorndyke said.
“Of course I can. Used we not to sail a yacht together when we were students?”
“To be sure we did; and we will again before we die. And now as to your method of locating this house. Here is a pocket reading-lamp which you can hook on the carriage lining. This notebook can be fixed to the board with an india-rubber band—thus. You observe that the thoughtful Polton has stuck a piece of thread on the glass of the compass to serve as a lubber’s line. This is how you will proceed. As soon as you are locked in the carriage, light your lamp—better have a book with you in case the light is noticed—take out your watch and put the board on your knee, keeping its long side exactly in a line with the axis of the carriage. Then enter in one narrow column of your notebook the time, in the other the direction shown by the compass, and in the broad column any particulars, including the number of steps the horse makes in a minute. Like this.”
He took a loose sheet of paper and made one or two sample entries on it in pencil, thus—
“9:40 S.E. Start from home.
9:41 S.W. Granite setts.
9:43 S.W. Wood pavement. Hoofs 104.
9:47 W. by S Granite crossing. Macadam—
and so on. Note every change of direction, with the time; and whenever you hear or feel anything from outside, note it, with the time and direction; and don’t forget to note any variations in the horse’s pace. You follow the process?”
“Perfectly. But do you think the method is accurate enough to fix the position of a house? Remember, this is only a pocket-compass with no dial, and it will jump frightfully. And the mode of estimating distance is very rough.”
“That is all perfectly true,” Thorndyke answered. “But you are overlooking certain important facts. The track-chart that you will produce can be checked by other data. The house, for instance, has a covered way by which you could identify it if you knew approximately where to look for it. Then you must remember that your carriage is not travelling over a featureless plain. It is passing through streets which have a determined position and direction and which are accurately represented on the ordnance map. I think, Jervis, that, in spite of the apparent roughness of the method, if you make your observations carefully, we shall have no trouble in narrowing down the inquiry to a quite small area. If we get the chance, that is to say.”
“Yes, if we do. I am doubtful whether Mr. Weiss will require my services again, but I sincerely hope he will. It would be rare sport to locate his secret burrow, all unsuspected. But now I must really be off.”
“Goodbye, then,” said Thorndyke, slipping a well-sharpened pencil through the rubber band that fixed the notebook to the board. “Let me know how the adventure progresses—if it progresses at all—and remember, I hold your promise to come and see me again quite soon in any case.”
He handed me the board and the lamp, and, when I had slipped them into my pocket, we shook hands and I hurried away, a little uneasy at having left my charge so long.
III
“A Chiel’s Amang Ye Takin’ Notes”
The attitude of the suspicious man tends to generate in others the kind of conduct that seems to justify his suspicions. In most of us there lurks a certain strain of mischief which trustfulness disarms but distrust encourages. The inexperienced kitten which approaches us confidingly with arched back and upright tail, soliciting caresses, generally receives the gentle treatment that it expects; whereas the worldly-wise tomcat, who, in response to friendly advances, scampers away and grins at us suspiciously from the fancied security of an adjacent wall, impels us to accelerate his retreat with a well-directed clod.
Now the proceedings of Mr. H. Weiss resembled those of the tomcat aforesaid and invited an analogous reply. To a responsible professional man his extraordinary precautions were at once an affront and a challenge. Apart from graver considerations, I found myself dwelling with unholy pleasure on the prospect of locating the secret hiding-place from which he seemed to grin at me with such complacent defiance; and I lost no time and spared no trouble in preparing myself for the adventure. The very hansom which bore me from the Temple to Kennington Lane was utilized for a preliminary test of Thorndyke’s little apparatus. During the whole of that brief journey I watched the compass closely, noted the feel and sound of the road-material and timed the trotting of the horse. And the result was quite encouraging. It is true that the compass-needle oscillated wildly to the vibration of the cab, but still its oscillations took place around a definite point which was the average direction, and it was evident to me that the data it furnished were very fairly reliable. I felt very little doubt, after the preliminary trial, as to my being able to produce a moderately intelligible track-chart if only I should get an opportunity to exercise my skill.
But it looked as if I should not. Mr. Weiss’s promise to send for me again soon was not fulfilled. Three days passed and still he made no sign. I began to fear that I had been too outspoken; that the shuttered carriage had gone forth to seek some more confiding and easygoing practitioner, and that our elaborate preparations had been made in vain. When the fourth day drew towards a close and still no summons had come, I was disposed reluctantly to write the case off as a lost opportunity.
And at that moment, in the midst of my regrets, the bottle-boy thrust an uncomely head in at the door. His voice was coarse, his accent was hideous, and
