"This is a case of 'sermons in stones,'" I replied, "and a very serious case. I wonder you have escaped with all those pretty brilliants on your sleeves."

"But I haven't escaped," she cried; "why, you're not up to date. Don't you know that I lost a marquise brooch at the Hayes's dance the other evening? I have never heard the last of it from my husband, who will not believe for a minute that I did not lose it in the crowd."

"And you yourself believe----"

"That it was stolen, of course. I pin my brooches too well to lose them--some one took it in the same cruel way that Lady Faber's rubies have been taken. Isn't it really awful to think that at every party we go to thieves go with us? It's enough to make one emigrate to the shires."

She fell to the flippant mood again, for nothing could keep her from that; and as there was obviously nothing to be learnt from her, I listened to her chatter sufferingly.

"But we were going to suspect people," she continued suddenly, "and we have not done it. As we can't begin with the curate, let's take the slim young man opposite. Hasn't he what Sheridan calls--but there, I mustn't say it; you know--a something disinheriting countenance?"

"He eats too many jam tarts and drinks too much lemonade to be a criminal," I replied; "besides, he is not occupied, you'll have to look in the ball-room."

"I can just see the top of the men's heads," said she, craning her neck forward in the effort. "Have you noticed that when a man is dancing, either he star-gazes in ecstasy, as though he were in heaven, or looks down to his boots--well, as if it were the other thing?"

"Possibly," said I; "but you're not going to const.i.tute yourself a _vehmgericht_ from seeing the top of people's heads."

"Indeed," she cried, "that shows how little you know; there is more character in the crown of an old man's head than is dreamt of in your philosophy, as what's-his-name says. Look at that shining roof bobbing up there, for instance; that is the halo of port and honesty--and a difficulty in dancing the polka. Oh! that mine enemy would dance the polka--especially if he were stout."

"Do you really possess an enemy?" I asked, as she fell into a vulgar burst of laughter at her own humor; but she said,--

"Do I possess one? Go and discuss me with the other women--that's what I tell all my partners to do; and they come back and report to me. It's as good as a play!"

"It must be," said I, "a complete extravaganza. But your enemy has finished his exercise, and they are going to play a waltz. Shall I take you down?"

"Yes," she cried, "and don't forget to discuss me. Oh, these crushes!"

She said this as we came to the press upon the corner of the stairs leading to the ball-room, a corner where she was pushed desperately against the banisters. The vigor of the polka had sent an army of dancers to the conservatory, and for some minutes we could neither descend nor go back; but when the press was somewhat relieved, and she made an effort to progress, her dress caught in a spike of the iron-work, and the top of a panel of silk which went down one side of it was ripped open and left hanging. For a minute she did not notice the mishap; but as the torn panel of silk fell away slightly from the more substantial portion of her dress, I observed, pinned to the inner side of it, a large crescent brooch of diamonds. In the same instant she turned with indescribable quickness, and made good the damage. But her face was scarlet in the flush of its color; and she looked at me with questioning eyes.

"What a miserable accident," she said. "I have spoilt my gown."

"Have you?" said I sympathetically, "I hope it was not my clumsiness--but really there doesn't seem much damage done. Did you tear it in front?"

There was need of very great restraint in saying this. Though I stood simply palpitating with amazement, and had to make some show of examining her gown, I knew that even an ill-judged word might undo the whole good of the amazing discovery, and deprive me of that which appeared to be one of the most astounding stories of the year. To put an end to the interview, I asked her laughingly if she would not care to see one of the maids upstairs; and she jumped at the excuse, leaving me upon the landing to watch her hurriedly mounting to the bedroom story above.

When she was gone, I went back to the conservatory and drank a cup of tea, always the best promoter of clear thought; and for some ten minutes I turned the thing over in my mind. Who was Mrs. Sibyl Kavanagh, and why had she sewn a brooch of brilliants to the inside of a panel of her gown--sewn it in a place where it was as safely hid from sight as though buried in the Thames? A child could have given the answer--but a child would have overlooked many things which were vital to the development of the unavoidable conclusion of the discovery. The brooch that I had seen corresponded perfectly with the crescent of which Lady Dunholme was robbed--yet it was a brooch which a hundred women might have possessed; and if I had simply stepped down and told Lady Faber, "the thief you are entertaining is Mrs. Sibyl Kavanagh," a slander action with damages had trodden upon the heels of the folly. Yet I would have given a hundred pounds to have been allowed full inspection of the whole panel of the woman's dress--and I would have staked an equal sum that there had been found in it the pendant of the ripening rubies; a pendant which seemed to me the one certain clue that would end the series of jewel robberies, and the colossal mystery of the year. Now, however, the woman had gone upstairs to hide in another place whatever she had to hide; and for the time it was unlikely that a sudden searching of her dress would add to my knowledge.

A second cup of tea helped me still further on my path. It made quite clear to me the fact that the woman was the recipient of the stolen jewels, rather than the actual taker of them. She, clearly, could not use the scissors which had severed Lady Faber's pendant from the ruby belt. A skilful man had in all probability done that--but which man, or perhaps men? I had long felt that the season's robberies were the work of many hands. Chance had now marked for me one pair; but it was vastly more important to know the others. The punishment of the woman would scarce stop the widespread conspiracy; the arrest of her for the possession of a crescent brooch, hid suspiciously it is true, but a brooch of a pattern which abounded in every jeweler's shop from Kensington to Temple Bar, would have been consummate lunacy. Of course, I could have taken cab to Scotland Yard, and have told my tale; but with no other support, how far would that have availed me? If the history of the surpa.s.singly strange case were to be written, I knew that I must write it, and lose no moment in the work.

I had now got a sufficient grip upon the whole situation to act decisively, and my first step was to re-enter the ball-room, and to take a partner for the next waltz. We had made some turns before I discovered that Mrs. Kavanagh was again in the room, dancing with her usual dash, and seemingly in no way moved by the mishap. As we pa.s.sed in the press, she even smiled at me, saying, "I've set full sail again;" and her whole bearing convinced me of her belief that I had seen nothing.

At the end of my dance my own partner, a pretty little girl in pink, left me with the remark, "You're awfully stupid to-night! I ask you if you've seen _Manon Lescaut_, and the only thing you say is, 'The panel b.u.t.tons up, I thought so.'" This convinced me that it was dangerous to dance again, and I waited in the room only until the supper was ready, and Mrs. Kavanagh pa.s.sed me, making for the dining-room, on the arm of General Sharard. I had loitered to see what jewels she wore upon her dress; and when I had made a note of them, I slipped from the front door of the house un.o.bserved, and took a hansom to my place in Bond Street.

At the second ring of the bell my watchman opened the door to me; and while he stood staring with profound surprise, I walked straight to one of the jewel cases in which our cheaper jewels are kept, and took therefrom a spray of diamonds, and hooked it to the inside of my coat.

Then I sent the man upstairs to awaken Abel, and in five minutes my servant was with me, though he wore only his trousers and his shirt.

"Abel," said I, "there's good news for you. I'm on the path of the gang we're wanting."

"Good G.o.d, sir!" cried he, "you don't mean that!"

"Yes," said I, "there's a woman named Sibyl Kavanagh in it to begin with, and she's helped herself to a couple of diamond sprays, and a pendant of rubies at Lady Faber's to-night. One of the sprays I know she's got; if I could trace the pendant to her, the case would begin to look complete."

"Whew!" he e.j.a.c.u.l.a.t.ed, brightening up at the prospect of business. "I knew there was a woman in it all along--but this one, why, she's a regular flier, ain't she, sir?"

"We'll find out her history presently. I'm going straight back to Portman Square now. Follow me in a hansom, and when you get to the house, wait inside my brougham until I come. But before you do that, run round to Marlborough Street police-station and ask them if we can have ten or a dozen men ready to mark a house in Bayswater some time between this and six o'clock to-morrow morning."

"You're going to follow her home then?"

"Exactly, and if my wits can find a way I'm going to be her guest for ten minutes after she quits Lady Faber's. They're sure to let you have the men either at Marlborough Street or at the Harrow Road station. This business has been a disgrace to them quite long enough."

"That's so, sir; King told me yesterday that he'd bury his head in the sand if something didn't turn up soon. You haven't given me the exact address though."

"Because I haven't got it. I only know that the woman lives somewhere near St. Stephen's Church--she sits under, or on, one of the curates there. If you can get her address from her coachman, do so. But go and dress and be in Portman Square at the earliest possible moment."

It was now very near one o'clock, indeed the hour struck as I pa.s.sed the chapel in Orchard Street; and when I came into the square I found my own coachman waiting with the brougham at the corner by Baker Street. I told him, before I entered the house, to expect Abel; and not by any chance to draw up at Lady Faber's. Then I made my way quietly to the ball-room and observed Mrs. Kavanagh--I will not say dancing, but hurling herself through the last figure of the lancers. It was evident that she did not intend to quit yet awhile; and I left her to get some supper, choosing a seat near to the door of the dining-room, so that any one pa.s.sing must be seen by me. To my surprise, I had not been in the room ten minutes when she suddenly appeared in the hall, unattended, and her cloak wrapped round her; but she pa.s.sed without perceiving me; and I, waiting until I heard the hall door close, went out instantly and got my wraps. Many of the guests had left already, but a few carriages and cabs were in the square, and a linkman seemed busy in the distribution of unlimited potations. It occurred to me that if Abel had not got the woman's address, this man might give it to me, and I put the plain question to him.

"That lady who just left," said I, "did she have a carriage or a cab?"

"Oh, you mean Mrs. Kevenner," he answered thickly, "she's a keb, she is, allus takes a hansom, sir; 192, Westbourne Park; I don't want to ask when I see her, sir."

"Thank you," said I, "she has dropped a piece of jewelry in the hall, and I thought I would drive round and return it to her."

He looked surprised, at the notion, perhaps, of any one returning anything found in a London ball-room but I left him with his astonishment and entered my carriage. There I found Abel crouching down under the front seat, and he met me with a piteous plea that the woman had no coachman, and that he had failed to obtain her address.

"Never mind that," said I, as we drove off sharply, "what did they say at the station?"

"They wanted to bring a force of police round, and arrest every one in the house, sir. I had trouble enough to hold them in, I'm sure. But I said that we'd sit down and watch if they made any fuss, and then they gave in. It's agreed now that a dozen men will be at the Harrow Road station at your call till morning. They've a wonderful confidence in you, sir."

"It's a pity they haven't more confidence in themselves--but, anyway, we are in luck. The woman's address is 192, Westbourne Park, and I seem to remember that it is a square."

"I'm sure of it," said he; "it's a round square in the shape of an oblong, and one hundred and ninety two is at the side near Durham something or other; we can watch it easily from the palings."

After this, ten minutes' drive brought us to the place, and I found it as he had said, the "square" being really a triangle. Number one hundred and ninety two was a big house, its outer points gone much to decay, but lighted on its second and third floors; though so far as I could see, for the blinds of the drawing-room were up, no one was moving. This did not deter me, however, and, taking my stand with Abel at the corner where two great trees gave us perfect shelter, we waited silently for many minutes, to the astonishment of the constable upon the beat, with whom I soon settled; and to his satisfaction.

"Ah," said he, "I knew they was rum 'uns all along; they owe fourteen pounds for milk, and their butcher ain't paid; young men going in all night, too--why, there's one of them there now."

I looked through the trees at his words, and saw that he was right. A youth in an opera hat and a black coat was upon the doorstep of the house; and as the light of a street lamp fell upon his face, I recognized him. He was the boy who had eaten of the jam-tarts so plentifully at Lady Faber's--the youth with whom Sibyl Kavanagh had pretended to have no acquaintance when she talked to me in the conservatory. And at the sight of him, I knew that the moment had come.

"Abel," I said, "it's time you went. Tell the men to bring a short ladder with them. They'll have to come in by the balcony--but only when I make a sign. The signal will be the cracking of the gla.s.s of that lamp you can see upon the table there. Did you bring my pistol?"

"Would I forget that?" he asked; "I brought you two, and look out! for you may want them."

"I know that," said I, "but I depend upon you. Get back at the earliest possible moment, and don't act until I give the signal. It will mean that the clue is complete."

He nodded his head, and disappeared quickly in the direction where the carriage was; but I went straight up to the house, and knocked loudly upon the door. To my surprise, it was opened at once by a thick-set man in livery, who did not appear at all astonished to see me.

"They're upstairs, sir, will you go up?" said he.

"Certainly," said I, taking him at his word. "Lead the way."