'At any rate,' Mr. Hawtrey continued, 'I see nothing at present but to let the matter go on, and for you to obtain, if possible, some decisive proof of the man's connection with these letters. So far we have really only the most shadowy grounds for our suspicion against him.'

Again Mr. Slippen nodded, this time more openly and decisively.

'Quite the most shadowy, Mr. Hawtrey. I am far from saying that he may not be the man, but beyond his having, as I understand, a grievance of very many years' duration against yourself there is really nothing whatever to connect him with the affair.'

'Nothing, Mr. Slippen. It is, in fact, simply because there is no one else against whom we have even such slight grounds as this to go upon, that we suspect this fellow of being the author of these rascally communications.'

'You will understand, Mr. Hawtrey, that being employed by you I consider it my duty to let you know exactly the light in which the matter strikes me. Of course, I do not know the man as you do, but from what I have learnt from Captain Hampton he seems to be an unprincipled blackguard; a man who has been concerned in various shady transactions on the turf, and who has come down to the rank of the lowest class of betting men; a fellow who pays his bets when he has made a winning book on a race and is a welsher when he loses.

'Of course, it may be that such a man is of so vindictive a nature that he may have taken all this trouble simply to annoy you, but I cannot help thinking that if he had embarked upon it he would have played his hand so as not only to annoy but to extort money to cease that annoyance. Now the writer of these letters has certainly not done that. Had he had any idea of extorting money he would have sent some sort of private intimation to you, by means of a cautiously worded letter, to the effect that an arrangement could be made by which the thing could be put a stop to. You have received no such missive; therefore, if this man is the author he is simply a malicious scoundrel, and not, in this instance at any rate, a clever rogue, as I should certainly have expected to find him from his antecedents.'

'That is to say, you do not think he is the man?'

'Yes, I think it comes almost to that, Mr. Hawtrey. I do not know him, and, of course, he may be the man, but I own that I shall be a good deal surprised if I find that he is so. Still, in the absence of any other clue whatever, I propose to follow this up. It will be something at least to clear it out of the way and to have done with it. I shall detail my boy to watch the public-house till the man comes to it, and then to find out where he lives and what are his habits; to follow his footsteps and take note of every place where he posts a letter. We shall get, at any rate, negative evidence that way. If, for instance, a letter is posted in the south of London, and we know that on that day the man never went out of Islington, I think that it will be very strong proof that he has nothing to do with the matter. Of course the reverse would not be so convincing the other way; but if we had the coincidence, three or four times repeated, of the letter bearing the mark of a district in which he had dropped one into the post, we should feel that we were a long way towards proving his connection with the affair.'

'Quite so,' Mr. Hawtrey agreed; 'that will, as you say, either go far to confirm our suspicions, or will altogether clear the ground so far as he is concerned, and we must then look for a clue in some other direction altogether.'

That afternoon Captain Hampton, having nothing to do, made his way up to Islington. The lad was not to be put on the watch until the next morning, and he thought that he might see this man at the public-house he frequented, and perhaps glean something from any conversation he might have with the men he met there. After some inquiry as to the direction of Frogmore Street, he turned up the Liverpool Road, and had gone but a few hundred yards when his eye fell on a couple engaged in earnest conversation on the raised walk, on the opposite side of the street. He paused abruptly in his stride. One was unquestionably the man for whom he was seeking. He was better dressed than when he had seen him before, and had more the air of a gentleman, but there could be no question as to his identity. The other was as unmistakably Dorothy Hawtrey.