there was something about the corner house mystery that gripped the public imagination. there was about it both the realism and the romance that always go to make up a popular sensation.

in the first place, the corner house was already marked as the scene of one unsolved tragedy. for years it had been shut up, for years the boys of the locality had challenged one another to go down the area steps after dark, for years nobody had crossed the threshold. then the door had been left open for the public eye to look on another tragedy.

the victim was no ordinary man either. people flocked to view the body as morbid folks will do on such occasions. the victim of the crime was no more attractive in death than he had been in life. there were the crooked limbs, the hideous hooked nose, the claws with the orange splashes on them.

but nobody identified the dead man; the police had not expected anything of the kind. the inquest had been formally opened at the corner house, and at the suggestion of sergeant prout, who had the case in hand, was adjourned for a fortnight. it was hard to get the people out of the house afterwards.

they were gone out at last, and sergeant prout was left to make his investigations in peace. up to now he had hardly as much as examined the body. an attempt had been made to find the owner of the house, or the agents, but without success.

"it's a queer thing," said prout, scratching his snaky little head reflectively; "a very queer thing. now here's a house for you. given a man of energy and pluck who has learnt its story, and what is to prevent his taking possession and living here as if the place was his own? he comes and picks the lock, he has his servants in, and gives out that he is jones or robinson, and there's an end of it so long as he holds his head high and pays his creditors. of course there is the risk of the real man turning up, but criminals must always take chances. in a way that's what happened. the poor fellow was lured here to be murdered by some one who pretended that the house was his. it's a very pretty case."

it was a puzzling one, too. every policeman who had been on night duty in lytton avenue for months was closely examined. once or twice a night the doors of the house had been tried without effect. nobody had ever been seen to come away or enter. no suspicious characters had been seen loafing about. not one of the officers had ever seen a light in the place.

"i'll go and look at the gas meter," said prout.

he was an efficient officer in his way, only, like most members of the force, he lacked imagination. give him something to work on, and there was not a more efficient detective in new scotland yard. but there was no clue here, so he had to fall back on the old familiar methods.

here was the gas meter under the stairs as usual. behind it was the grimy, dirty card, which showed no entry for years. it was marked "taken 5 feb.," in other words the meter had been read the day the owner had disappeared. by reading the index prout saw that a hundred odd cubic feet of gas had been used since.

here was something to go upon. beyond doubt that gas had been used lately. prout made a careful examination of the burners, sniffing and blowing at all of them. he found out one thing, only the burners in the hall and the bedroom where the murdered man had been found had been used for a long time. in a bedroom at the top of the house was a paraffin lamp with quite a new wick in it. with a stump of pencil prout made a rapid calculation on the wall-paper.

"lamp used by murderer waiting for his victim," he deduced. "did not want any more light than was necessary, so probably lay low in a back room. when the hour for the victim came, lighted the hall gas so as not to look suspicious. then why the dickens didn't the officer on duty notice it?"

"because it wasn't there when he passed, prout," said a quick voice that caused the detective to turn with a start. "there was a confederate, of course. nothing easier than for the confederate to listen for the officer's footsteps and put out the gas till he had gone by. other people didn't matter."

"right as usual, mr. lawrence," said prout, beaming approvingly on the great novelist. "why don't you come and join the force?"

lawrence modestly disclaimed the compliment. as a strong romantic writer he found a fascination in crimes of this kind; indeed, he boasted that practically all his living dramas were founded on life. he had a wonderful faculty for tracing the motive of a crime many a useful hint had he given to scotland yard.

"what's the theory here, sir?" prout asked respectfully.

"a vulgar one," said lawrence. "robbery either from the person or indirectly. i don't see how anybody could possibly be jealous of a poor misshapen creature like that. we can put the socialistic element out of the case. have you found anything?"

prout had found nothing. he had not had time yet to examine the deceased's coat and clothing. he was just about to do so. the first examination disclosed a pocketbook containing some score of more or less recent pawn-tickets made out in various names and a letter in an envelope.

"this looks like business," prout exclaimed. "the letter is not sealed. anyway, it was written here with the pen on the mantelpiece and that penny bottle of ink; see how pale it is and what shabby paper, evidently a ha'porth purchased from some huckster's shop. isn't that right, sir?"

prout scrawled in his pocketbook with the pen. the ink was just the same pallid hue. the pen was a "j," and the letter had evidently been written with a "j" too. prout had every reason to be satisfied.

"what do you think of the letter, sir?" prout asked.

there was no date and no address. there was a deal of flourish about the letter as if the writer had learned his craft abroad. it ran as follows:

dear friend and partner,--at last the luck of the deuce has departed and my virtue has its own reward. i have found my man. at first my man blustered, but logic, mon cher, logic gets the best of temper always. i parted with him and he parted with ￡400. in sovereigns. mark the cunning of the man! no notes or cheques for him. but money in cash i dare not send to you. therefore i have changed my gold for notes, and ￡200 in forty lovely crisp bits of paper i forward herewith. they are numbered from 190753 to 190792. this i tell you for precaution's sake. i am waiting for the cipher from k and this i will enclose. next saturday i propose to salute you. till then with my most distinguished admiration,

number one.

"what do you think of that?" prout asked.

"proves robbery," lawrence said, crisply. "the murderer got away with the notes, but knew nothing of the letter. you go your way and i'll go mine. i am greatly mistaken if i don't throw a strong light on the mystery yet."

"you mean that you have a clue, sir."

"certainly i do. this is a most amazing case. why, it is copied from the plot of one of my own novels. and, stranger still, that novel has not yet been written!"