How Green had contrived to find out the address to which Mullen was having his letters sent there was no evidence to show. Whether it was due to a singularly lucky fluke or to his own astuteness I could not say, and am not likely ever to know, but I quite realised and understood that it was possible for him to have made such a discovery. And I recognised and understood also that, after having read the letter which gave him the clue to Mullen’s connection with Mrs. Stanley Burgoyne, the other facts which he had ferreted out in regard to Mullen’s parentage would not be difficult to arrive at. What I could _not_ understand, however, was by what means he had succeeded in intercepting Mullen’s letters. If Green had been an official from Scotland Yard he would no doubt be allowed to intercept letters which might be written by or addressed to suspected persons, but that the postal authorities would permit a private inquiry agent to tamper with their mail bags was not to be entertained. That Green was staying in the same house as Mullen, and was able in that way to lay hands on the latter’s correspondence, was very unlikely. Nor was it likely that my late inquiry agent had succeeded in bribing a postman, for though it may not be impossible to find dishonest postmen, the odds are very much against finding the dishonest man in the one particular office with the mails of which one wishes to tamper. A far more probable theory was that which had at first occurred to me, namely, that the letters had been directed to the care of a tobacconist, or, more likely still, of a hairdresser. It is matter of common knowledge that many hairdressers add to their business takings by allowing letters, on each of which a fee of one penny is charged, to be addressed to their care. Though generally implying a not very creditable connection, these letters are, as a rule, of no more criminal character than assignations with people to whom the recipient has thought it unadvisable to give his real name or address, or whose letters he is anxious should not come under the notice of his family. If Green had intercepted the letters at a tobacconist’s shop, the first thing to find out was where that tobacconist’s shop was situated, and the only way to do so would be to trace the inquiry agent’s recent movements. Hence I decided that I could not do better than run down to Yarby again and see what could be learned about him. But before I could do this with safety I should have to ascertain whether the body had been found, and whether suspicions of foul play were entertained, as in that case it would not be advisable to visit the neighbourhood for the present. The morning paper of the following day settled that point satisfactorily, for on opening my “Daily News” I read the following announcement:--