Chapter EIGHT

Many of our most important modern inventions have been forestalled by the Chinese, for whom we should have the greater regard in that they are not Christians. Gunpowder, False Money, the art of Printing, Diplomacy, Propaganda, Prison Fortunes, Taximeters and the Strike--all these are of the extreme Orient. But what have I to do with all these? It is of the Mariner's Compass that I sing--which also was first spotted by the Chink.

Now of the various forms of Mariner's Compass there is one with which some few of my readers may be acquainted. It is used in certain scientific experiments which have nothing to do with pointing to the North, but with the measurement of delicate electrical hints. The needle swings on a jewelled pivot, very nicely balanced, encased in a small round box about an inch across, covered in with glass so that no dust can affect the very sensitive affair; and at the side there is a little stud on a spring which you press with your finger when you want to fix and register the pointing of the needle. So long as you press the stud the needle stands firm. When you release the stud the needle trembles again.

All very interesting. But what of it?

Wait a moment. Retain this clearly in your mind, and I will proceed to the second point.

It has been remarked by the less stupid of psychologists--and that is not saying much--that cunning and intelligence are not often combined. Conversely, as Dr. Nancy Neerly shrewdly remarked, when her assistant at the Hospital for Nervous Diseases, gonophed her microscope, extreme incompetence is often accompanied by cunning. Nothing is more cunning than your half-wit.

Getting that principle firmly into your head, you will appreciate that when Professor de Bohun slunk out in the evening after his cousin's departure for town, into the neighbouring suburban villas of Bakeham (which, for one thing, fringed the Park--the de Bohuns had long ago screened it by a dense row of quickly-growing timber--and for another, provided the Home Secretary with a considerable part of his insufficient income) his action was not unconnected with that upon which his mind had been exercised for now nearly twenty-four hours.

He sought a policeman, and said with a sudden squeak which made that high official jump:

"Oh! Can you tell me if anyone round here sells scientific instruments? Optical instruments? Electrical instruments? ... Instruments?"

"Wot?" said the policeman.

"Let us say ... ah, for instance," went on the squeaky voice, "clinometers.... Shall we say Clinometers? Clinometers? ... Yes! Clinometers!"

"Pass along!" said the policeman. "Pass along!" And there was that in his eye of a man who hesitates between a verdict of lunacy and arrest for leg-pull.

"But, Constable ..." pleaded the unfortunate cadet of an ancient house.

"Pass on! Pass on!" boomed the tyrant, and as there was a difference of at least three octaves between the two men's voices, the unfortunate Professor obeyed the double bass, crossed the street at the risk of his life, and wandered inanely past the shop windows.

But there is a Providence for such as he, as also for drunkards and babes; and there, right before him, was an ancient bow window of bottle-glass panes; the name of the shop in old Georgian script; the information that it had been founded in 1805; and, behind the glass, two telescopes, a microscope, a clock, several watches, and a sextant of immense age.

The Professor went in.

"What I want ... ah!" he said. Then his eye fell upon the very thing he desired. It lay there in a glass case, and the owner of the shop, no younger than his customer, brought it out with a palsied hand.

"That's it," said the Professor, nodding genially. "That's it. That's what I want. That's it." Slipping it into his pocket, he made for the door, nodding good day.

"Hi! Mister! That'll be five guineas," said the ancient. Oh! vileness of avaricious age! He had seen his client coming out by the garden gate by the Great House, he had noted guilty haste, he had noted academic idiocy, and he charged accordingly.

"Oh, yes! Of course ... ah! _What_! Five guineas? ... five _guineas_! FIVE GUINEAS!"

It was a sickener. But the wages of Sin is Death. He must have it--or something of the sort. And he must have it now, before Humphrey got home. Sin will not wait.

Believe me or not, but there was positively a flush upon the yellow cheek of the hoary intriguer, a flush that contrasted charmingly with his straggling white whiskers, as he parted with two half crowns and a note. It was a severe struggle. To comfort himself he pressed the stud again. Yes, it worked all right. He toddled back, and got in at the very moment when his cousin's car was buzzing up the drive, back from London.

Professor de Bohun was determined to lose no time. He got rid of his overcoat and his hat with surprising agility, and met the master of the house at the door as though he had been in for hours.

But his was not a temperament to introduce a subject with finesse. He went blindly at it.

"Humphrey," he said, ere ever the Home Secretary was across the step, "I want to see you. I want to see you now ... yes, now ... rather urgently.... I want to see you now."

The Man of Little Peace nodded wearily.

"Come along," he said.

His mind jumped back to the false scent of the morning. He suddenly wondered whether, after all, Cousin Bill was going to confess? Galton's statement had been clear enough. He had said in so many words that he had _seen_ an emerald in the Professor's hand. And the head of the family would have believed anything, almost of the Professor in the way of such follies since the great Mullingar affair.

"What is it, Bill?" he said, as he shut the door of his study.

"Ah!" said the Ancient, almost archly. "What do you think? The E-M-E-R-A-L-D! Eh? Eh?"

He searched in his pocket. Humphrey de Bohun looked to see the jewel appear. Not at all. What appeared was a little round brass box, glass cased, and in it a trembling needle, that shook and shivered like a gossamer in a breeze.

"Now, my dear Humphrey," said the Professor, "let us take two chairs; yes ... two chairs ... two chairs. Ah! yes, two chairs." They took two chairs. "And let me pull up this little table...." He had become almost businesslike, not to say sprightly, in concentrating upon what he was about to do.

"Now, then; here we are, we two on these two chairs as it were, are we not? Yes! And here you see this little instrument, do you not? Yes! And do you know what it does ... what it is? What it is ...? It's a talcometer."

"A what?" said the Home Secretary.

"A talcometer," said Professor de Bohun, lying freely, and puffing slightly after the effort. "Now, Humphrey, I want you to watch something. To watch something, eh! Ah! yes. You have, I take it--ah!--or Marjorie has, or some one has a jewel--sure to have one. A diamond, say. Any stone--crystal. A stone, at any rate...."

"I don't know," began Humphrey de Bohun, wondering what was to be. "Will this do?" he asked, leaning over towards his writing table and pulling off it the little crystal Chinese god which was used to weight down the papers which he had abandoned there so many days.

Anything would do for the deceitful pedant. He nodded cheerfully.

"Yes," he said, "so long as it's crystal. Anything crystal. Crystal." Then he added, "Now, Humphrey, watch. Here," holding the little round brass disk with its trembling needle, "I have our talcometer. Now here," moving the Chinese god into line with the axis round which the tiny filament of metal trembled, "here we have this talcometer, _and_ the crystal. Eh! _And_ the crystal.... Now watch, Humphrey!"

Holding the little round brass case with his left finger and thumb, he gradually with his right hand approached the heathenish idol, sliding the False God slowly along the polished table-top towards the instrument. It came closer and closer. It was at 9 inches, 6 inches, 3 inches, ... but there was as yet no apparent effect, when, suddenly, with the Pot-bellied Dwarf Deity at about 2 inches off, or a little less, the needle behaved like a pointer: it stood immovable, held rigidly by some strange force. The stud, dear friends, but how could Humphrey de Bohun know that?

"There! You see that? See that? See that?" squeaked the Professor triumphantly. "Now I want you to test it for yourself. Move the little devil away! Move it yourself! Humphrey, move it yourself!"

Humphrey de Bohun very slowly pushed back the crystal, and almost immediately the needle trembled again.

"There!" said the Professor in happy confidence, leaning back. "There! What did I tell you?"

"Well, what of it, Bill?" said the harassed master.

"What of it?" answered his cousin. "The Emerald. Ah! the Emerald!" and he rubbed his hands together.

"I don't understand a word you're saying," said poor Humphrey.

The Professor leaned forward and tapped his cousin twice upon the shoulder with that knotted forefinger.

"That instrument," he said, as solemnly as such a voice can say anything, "tells a crystal close at hand. According to the cube of the distance. I have to use it perpetually. Very well known. German, you know--wonderful people, the Germans. It was Meitz's idea," he went on, adding verisimilitude by the effective use of detail. "But _he_ couldn't have done it without Speitzer. Often like that in research work. Any doubt about a crystal's character. Even amorphous--put that thing close enough, and it points at once. Now do you see? Eh! Now do you see?"

"Not exactly," said Humphrey de Bohun.

"Why, it's plain enough! I hadn't thought of it. It suddenly occurred to me. It suddenly came to me while you were off to London. Here I had what could solve all our troubles. I put it first here, then there. Everywhere I could. Went on for an hour--all over the room! All over the rug where it dropped. Then one of your guests came in. I didn't want to be seen at it. I was putting it back into my pocket when my hand came close by the side of his coat. Bless my heart! It pointed!"

He leant forward again and tapped his cousin more solemnly still, this time on the chest. "Mark my words! That young man's got it!"

"Which young man?" said Humphrey, remembering what counter accusation the Professor would naturally make, and thinking at once of Galton.

"That young writing fellow," said Cousin Bill. "That newspaper chap McTaggart. McTaggart, McTaggart, McTaggart, McTaggart, McTaggart."

Humphrey de Bohun hesitated. "My dear Bill," he said, "you never know. He might have had something else in his pocket--also crystal, or--I don't know ... something."

The Professor wagged his head with all the dignity of a goat.

"Won't work, Humphrey!" he said. "Won't work! One can always tell the size by the distance. It wasn't some ring or small thing of that kind. Besides which, he wouldn't have such a small thing of his own in his pocket. No, the Emerald's there all right. And I'll tell you something that makes me surer still. I took occasion to brush up against him--there was a hard slab in that pocket, Humphrey. In that pocket. A small, hard slab! Slab! ... Hard slab! ..."

An awful task arose in the conscience of Humphrey de Bohun. He must play the spy again. He must mistrust yet another guest.

But wait! Should he tell the great detective when he arrived? No. It would be only fair to seek the young man first and warn him. But he hesitated and he put it off. He would wait till dinner time, or nearly dinner, when the poor fellow was changing. He would make it quite clear that there would be no consequences--only, he must confess and restore. Then he suddenly thought of what would happen if he drew blank, as he had in the case of the strange being before him. But he was in some agony.