Had such knowledge existed, it must inevitably have been divulged to him. The police, under the direction of Inspector Whyland, were engaged in passing a fine-toothed comb through the Paddington district, and the minor offenders disturbed in this process were as concerned as a colony of ants unearthed by a spade. Mr. Ludgrove was visited furtively late at night by anxious people seeking advice how to conceal the evidence of their misdemeanours from the prying eyes of the police. He questioned each of these closely, but the more he did so the more he became convinced that none of them had the slightest inkling of the perpetrator of the murders. Another section of his clients, however, equally furtive and mysterious, had clues in plenty, which they seemed to think entitled them to some reward. These, after assuring themselves that no one could overhear them, would produce an incoherent story of how one of their neighbours must be the criminal. He had been heard to utter threats that he would do some one in some day, he had been in Praed Street on the night when Mr. Tovey was murdered, in the neighbourhood of Paddington station when Mr. Pargent was killed. Others, again, had met a muffled figure brandishing a knife, or had seen a dark man with a beard standing in the shadow thrown by a projecting wall. Two or three searching questions were always sufficient to prove that their suspicions were baseless. The murders in Praed Street were thus peculiar in the annals of crime. In nearly every case of a crime being committed, there are others besides the criminal who know all the facts. The police know this, but their great difficulty is to secure evidence sufficiently convincing to lead to a conviction. There is a certain _esprit de corps_ in the constant strife between the professional criminal and the police, and those who know are careful to keep their knowledge to themselves. But in this case, had there been any of the inhabitants of the district in the secret, Mr. Ludgrove would have obtained some hint of it. It seemed conclusive that the criminal was either working alone and independently, or came from some other district.