It was, indeed, only two days after Plummer's visit that Kerrett brought into Hewitt's private room the card of the Rev. James Potswood, with a request for a consultation. Mr. Potswood's name was known to Hewitt, as, indeed, it was to many people, as that of a most devoted clergyman, rector of a large parish in north-west London, who devoted not only all his time and personal strength to his work, but also spent every penny of his private income on his parish. It was not a small income that Mr. Potswood spent in this unselfish way, for he came of a wealthy family, and though a good part of his parish was inhabited by well-to-do people, there was quite enough poverty and distress in the poorer quarters to cause this excellent man often to regret that his resources were not even larger. He was a spare active grey-whiskered man of nearly sixty, with prominent and not very handsome features, though his face was full of frank and simple kindliness. "My errand, Mr. Hewitt," he said, "is of a rather vague, not to say visionary, character, and I doubt if you can help me. But at any rate I will explain the trouble as well as I can. In the first place, am I right in supposing that you were in some way professionally engaged in connection with that extraordinary case of murder a week or so ago--the case in which a man named Denson was found dead on the steps by the Duke of York's column?" "Yes--and no," Hewitt answered. "I was professionally engaged on a certain matter about which you will not wish me to particularise--since it is the business of a client--and in course of it I came upon the other affair." "Then before I ask what you know of that mysterious event, Mr. Hewitt, I will tell you my story, so that you may judge whether you are able to reveal anything, or to do anything. Of course, what I say is in the strictest confidence." "Of course."