'But you have certainly one enemy who is just the sort of man to conceive and carry out such a blackguard business as this--I mean that man who was impertinent to you on the racecourse, and whose history you told us that evening.' 'I had not thought of him. Yes, that suggestion is certainly a probable one. He is evidently deeply impressed with the sense of injury, though, Heaven knows, I did not have the slightest ill-feeling against him, but was driven to do what I did by his own courses, and especially by his father's earnest request that he should not succeed him. There is no doubt as to his malice, and there can be as little as to his unscrupulousness.' 'Danvers and I were both of opinion, Mr. Hawtrey, that by his tone and manner when he spoke to you about payment of debts, that he had already done you some injury or had some distinct plan in his head. At that time your daughter was not engaged to Lord Halliburn, and his ideas may have been vague ones until the public notice of the engagement met his eye, when he may have said to himself, "This is my opportunity for taking my revenge, by annoying both father and daughter."' 'It is possible, Ned. I can hardly bring myself to think that the son of my old friend would be capable of such a dastardly action, but I admit that there is at least a motive in his case, and that I can see none in that of anyone else.' 'At any rate, Mr. Hawtrey, here is a clue worth following, and as I have nothing whatever to do, and my own time hangs rather heavily on my hands, I will, if you will allow me, undertake to follow it up.' 'But with no evidence against him, not a particle, what can you do, Ned?' 'My business will be to get evidence. The first thing is to find out where the fellow lives, and to have him watched and followed, and if possible, caught in the act of posting one of these letters.' 'Remember, Ned, I would above all things avoid publicity, for Dorothy's sake. Nothing is more hateful than for a girl to be talked about, and it is only as a last resource that I would bring a charge against him at the Police Court.' 'I can quite understand that, and will certainly call in no police to my aid until I have previously consulted you and received your sanction to do so. It will be easy enough to find him, for I should know him in an instant, and shall probably meet him at the first racecourse I go to. It is not as if I knew nothing of his habits.' For the next week Captain Hampton frequented every racecourse within a short distance of London, but without meeting the man he was looking for. Men of the same class were there in scores--some boisterous, some oily-mouthed, some unmitigated ruffians, others crafty rogues. Several times he accosted one of these men, and inquired if he had seen a betting man having the name of Marvel on his hat; each time the response was the same.