Of the many devices introduced by detective writers to arrest and hold the readers' attention, some are admittedly legitimate and used by best authors. Others are unfair; and still others were permissible but have become so hackneyed as to be taboo.
Snow and Rain
In "Monsieur Lecoq" much depends on the footprints in the snow. Thereafter in the first chapter of nearly every detective story we are informed that "a light snow had fallen the evening before." Then witnesses are brought to prove the exact hour the snow began to fall, and the moment it stopped. This fixes the time of the murder, and the footprints in the snow lead to or from the criminal as the author may decree.
Later this light snow was varied by "a gentle rain, the first for two weeks," that left paths and flower-beds soft for the indicative footprints.
In "A Study in Scarlet" there is a torrential downpour. This is in order to soften the clay of the garden path sufficiently to take footmarks; but it is a little overdone, for the torrents pour down all night, and would have obliterated any footprints save those made by a fictive criminal for the benefit of a fictive detective.
This same rain is treated a little better by Miss Mary E. Wilkins in her story "The Long Arm,11 for she relates "There had been heavy rain in the morning of the 17th, and the soil is a sticky clay. I examined it at daybreak on the morning of the 18th and, as it had not rained during the night the footprints were as fresh as if they had just been made."
This is the same accurately scheduled, time-lock rain, but it is a little more logical than the cloudburst variety.
If possible, then, act along without the light snow or the gentle rain or even the torrents. They seem almost indispensable, but endeavor for once to construct a crime without them.
Some Particularly Hackneyed Devices
Fog, though not so much of a factor here, is incessantly used in English detective stories. It is so obviously a convenient device for concealing crime, that it is the foundation of Richard Harding Davis's "In the Fog" and also of "A Mysterious Disappearance," "Big Bow Mystery," "The Masquerader," and scores of others.
Another hackneyed device is the secret panel in the wall, which slides open by pressing a hidden spring. This was overdone in sensational fiction, before Detective Stories began, but was seized upon as a valuable device for Mystery tales. But it is easily suspected, and in unsatisfactory in modern settings.
Avoid too, if you can, the packet of valuable papers that disclose secret plans of enormous political importance. This has been overdone, and the plot of Conan Doyle's "The Naval Treaty" has been paraphrased and parodied until it has become tiresome.
Another trite incident is the finding of a pistol engraved with initials, near the body of the victim. The youngest reader nowadays, knows better than to suspect the owner of those initials.
To quote from a personal letter of Mr. Burton E. Stevenson:
"If I were to find a murdered man,—which the Lord forbid!—and should also discover beside the body a pistol with a name on it or a visiting card or a monogrammed watch charm, or anything else of a clearly identifying character, I should conclude at once that the person thus identified was not guilty. This is a weakness which often annoys me in the modern detective story. When the hero's cane is found in the bushes near the body, and everyone concludes that the hero is therefore guilty, I put the book down with a sigh of disappointment."
A fine example of this mistaken device is in "The Villa Mystery, " by Herbert Flowerdew:
The old man was staring at him stupidly. Now suddenly his face became alive again.
"You think that I shot the master?" he whispered incredulously. "I wish to God it was me. Do you know this, Mr. Esmond?"
He was taking from his pocket a dainty lace-edged handkerchief, and as he passed it across to the young mean, Esmond recognized the subtle perfume it carried, even before his eyes fell on the embroidered initial, and his face paled.
"Well?" he said hoarsely.
Mason glanced apprehensively at the door, although it was locked, and dropped his voice to an even lower whisper.
"It was lying by the side of the master when I found him. That is why I did not send for the police. I wanted to give her time to get away."
The veriest ignoramus in the tricks of Detective Fiction would know better than to suspect the owner of that handkerchief! Again, we find this scene in "The Circular Staircase":
In one of the tulip beds back of the house an early blackbird was pecking viciously at something that glittered in the light. I picked my way gingerly over through the dew and stooped down: almost buried in the soft ground was a revolver! I scraped the earth off it with the tip of my shoe, and, picking it up, slipped it into my pocket. Not until I had got into my bedroom and double-locked the door did I venture to take it out and examine it. One look was all I needed. It was Halsey's revolver! I had unpacked it the day before and put it on his shaving stand, and there could be no mistake. His name was on a small silver plate on the handle.
I seemed to see a network closing around my boy, innocent as I knew he was. The revolver—I am afraid of them, but anxiety gave me courage to look through the barrel—the revolver had still two bullets in it. I could only breathe a prayer of thankfulness that I had found the revolver before any sharp-eyed detective had come around.
I decided to keep what clues I had, the cuff-link, the golf- stick and the revolver, in a secure place until I could see some reason for displaying them. The cuff-link had been dropped into a little filigree box on my toilet table. I opened the box and felt around for it. The box was empty—the cuff-link had disappeared!
Cuff-links, or other small articles kept for clues, invariably disappear in Detective Stories, and many authors seek to mislead by such devices, but the trained reader is not to be fooled by them.
Omit the use of a magpie, raven or parrot as an instrument for stealing jewels. A bird of this sort made an effective criminal when "The Jackdaw of Rheims" was written; but, though still a plausible one, the poor bird has been overworked and deserves a rest.
And oh, young writer, avoid, as you would the plague, the introduction of shreds or threads of wearing apparel as incriminating evidence! Probably this began with Lecoq's discovery of a few threads of brown wool, which were tom off by splinters, as a man wiped snow from a beam with his coat sleeve. This was credible and even plausible, and as it was the first time such a device had appeared in detective fiction it was acceptable. But how that poor detail has been abused and tortured ever since!
Devices Which Are Not Plausible
In "The Accomplice," an unusually good court-room story, by Frederick Trevor Hill, we have this sort of evidence reduced almost to an absurdity. To quote from page 13:
"The first error consisted in leaving the drippings of candle-grease on the veranda roof, and the second was in kneeling on those drippings before they were quite dry. As though it had been a hand gripping the skirt of the criminal, that wax held in its clutch, half a dozen threads of a hairy cloth, blue in color, and of a texture known to the trade as dress goods. When you have found the wearer of the cloth from which those threads were torn, gentlemen, you will have found the murderer of Mr. Gregory Shaw."
At the end of the book it was revealed that sure enough the criminal, who, however, was a man instead of the young woman at first suspected, had knelt in the candle drippings, and had left there bits of blue wool shreds from his trouser knees.
We can scarcely imagine a candle-dripping sufficiently tenacious to grasp in its clutch and hold for evidence a portion of material necessarily drawn tightly over the bent knees of the criminal. Even granting the especially hairy cloth from which the murderer obligingly had his costume made for the occasion, candle-grease of any sort does not possess such strongly adherent, not to say bull-dog, qualities as would allow it to clutch and keep pieces of that cloth.
Mr. Jacques Futrelle uses the thread clue with a little more plausibility, though still slightly forced:
The Thinking Machine opened his pocketbook and took from it the scarlet thread which he had picked from the rope of the flagpole.
"Here, I believe, is the real clue to the problem," he explained to Hatch. "What does it seem to be?"
Hatch examined it closely.
"I should say a strand from a Turkish bath robe," was his final judgment.
"Possibly. Ask some cloth expert what he makes of it, then if it sounds promising look into it. Find out if by any possibility it can be any part of any garment worn by any person in the apartment house."
"But, it's so slight " Hatch began.
"I know," the other interrupted, tartly. "It's slight, but I believe it is a part of the wearing apparel of the person, man or woman, who has four times attempted to kill Mr. Henley and who did kill the girl. Therefore it is important."
Of course this thread led to the capture of the criminal, and as it was found caught in a rope near the scene of the crime it was a fairly good clue; but as a matter of fact, the threads of Turkish toweling are of fairly stout calibre, and are not likely to be broken off as they trail across a rope. So much depends on the plausibility of these clues, that not only care but common sense must be exercised in their selection. In the Thinking Machine story, another scarlet thread from the same bath-robe attached itself importantly and conspicuously to a metal corner of a trunk, and so by the trail of red threads the criminal was hunted down. Here again we see the beautiful workings of the salted mine. In real life those tell-tale threads would have stayed stubbornly in their own warp or woof; or if they did leave their rightful abiding place they would creep behind the bureau or somehow get into the dust bin undiscovered.
In Samuel Gardenhire's story, "The Abduction of Mary Ellis," the discovery of the criminal hinges on a piece of brown wrapping-paper, on which the kidnappers wrote an advertisement asking for ransom. This paper, after passing through several hands, was examined microscopically by the Transcendent Detective, and he discovered wax and a strand or two of floss doll's hair. Now, think of the thousands of dolls that are bought and never leave a hair of their heads fastened by a bit of their own wax face to their wrapping paper! and then think of this doll intelligently leaving these traces at the critical juncture, where such a clue was necessary, and then judge for yourself the relationship between truth and fiction.
This habit of using shredded evidence is not confined to writers in our own language. An exceedingly good detective story is by a Russian, Anton Chekhov, and is called the "Safety Match." There was a bushy burdock growing under the window, which was greatly trampled. On its upper branches. Detective Dukovski succeeded in finding some fine hairs of dark blue wool. Now, had the bushy burdock pulled out a jagged piece of woolen cloth we might have forgiven it, but to catch and hold up for inspection a few fine hairs is drawing too long a bow. However, they cut off these twigs of burdock and care fully wrapped them in paper in true conventional style. These few fine hairs lead directly to the trousers of the murderer and the naive author quite calmly acknowledges his debt to an illustrious predecessor: "See what a fellow who has read Gaboriau can do!" he exclaimed, which is not too self-depreciatory, for even in the same story he has adapted to his own use many more of Lecoq's devices.
The most logical and plausible instance of detection by the means of tiny threads for clues is found in Mary E. Wilkins's "The Long Arm."
"I began to-day at the bottom—that is, with the room least likely to contain any clue, the parlour. I took a chalk-line and a yard-stick, and divided the floor into square yards, and every one of these squares I examined on my hands and knees. I found in this way literally nothing on the carpet but dust, lint, two common white pins, and three inches of blue sewing silk.
"At last I got the dustpan and brush, and yard by yard swept the floor. I took the sweepings in a white pasteboard box out into the yard in the strong sunlight, and examined them. There was nothing but dust and lint and five inches of brown woollen thread—evidently a ravelling of some dress material. The blue silk and the brown thread are the only possible clues which I found today and they are hardly possible. Rufus's wife can probably account for them."
These two threads were very naturally dropped from the clothing of a dressmaker, who has a perfect right to shed her snippings and ravelings wherever she may list.
It is wise to be careful in the use of shreds and threads that the author may not bring a smile to the face of the "gentle reader." Think of the absurdity of this statement, quoted from a modern English story:
It all began with the murder of Mr. Andrew Carrthwaite, at Palermo.
He had been found dead in the garden of his villa just outside the town, with a stiletto between his shoulder blades and a piece of rough Irish tweed, obviously torn from his assailant's coat, clutched tightly in his hand.
It would be interesting to see a hand that could tear a piece out of a coat of rough Irish tweed! The strength of such a clutch would put to blush the feats of the Murderer of the Rue Morgue.