The doctor knew too much to interrupt the young enthusiast, and so he let her run on until she ran down.  He was more used to the rules of evidence than she was, and could not accept her positive conclusion so readily as she would have liked to have him.  He knew that beginners are very apt to make what they think are discoveries.  But he had been an angler and knew the meaning of a yielding rod and an easy-running reel.  He said quietly,

“You are a most sagacious young lady, and a very pretty prima facie case it is that you make out.  I can see no proof that Mr. Kirkwood is not the same person as the M . . .  Ch . . . of the medical journal,—­that is, if I accept your explanation of the difference in the initials of these two names.  Even if there were a difference, that would not disprove their identity, for the initials of patients whose cases are reported by their physicians are often altered for the purpose of concealment.  I do not know, however, that Mr. Kirkwood has shown any special aversion to any particular color.  It might be interesting to inquire whether it is so, but it is a delicate matter.  I don’t exactly see whose business it is to investigate Mr. Maurice Kirkwood’s idiosyncrasies and constitutional history.  If he should have occasion to send for me at any time, he might tell me all about himself, in confidence, you know.  These old accounts from Baglivi are curious and interesting, but I am cautious about receiving any stories a hundred years old, if they involve an improbability, as his stories about the cure of the tarantula bite by music certainly do.  I am disposed to wait for future developments, bearing in mind, of course, the very singular case you have unearthed.  It wouldn’t be very strange if our young gentleman had to send for me before the season is over.  He is out a good deal before the dew is off the grass, which is rather risky in this neighborhood as autumn comes on.  I am somewhat curious, I confess, about the young man, but I do not meddle where I am not asked for or wanted, and I have found that eggs hatch just as well if you let them alone in the nest as if you take them out and shake them every day.  This is a wonderfully interesting supposition of yours, and may prove to be strictly in accordance with the facts.  But I do not think we have all the facts in this young man’s case.  If it were proved that he had an aversion to any color, it would greatly strengthen your case.  His ‘antipatia,’ as his man called it, must be one which covers a wide ground, to account for his self-isolation,—­and the color hypothesis seems as plausible as any.  But, my dear Miss Vincent, I think you had better leave your singular and striking hypothesis in my keeping for a while, rather than let it get abroad in a community like this, where so many tongues are in active exercise.  I will carefully study this paper, if you will leave it with me, and we will talk the whole matter over.  It is a fair subject for speculation, only we must keep quiet about it.”