"We met first in the train, the South Wales Express, you remember? I fancy you told me then that you had been in South Africa, in this bungled war, and had been either wounded or ill in some way. In fact you went so far as to say you had had 'necrosis of the jaw,' a thing I politely doubted because whatever it was it has left no perceptible scar. Of course it's damned impertinent of me to cross-examine you at all, or to ask _why_ you went to and why you left South Africa. But I don't mind confessing you inspire me with a good deal of interest. "Now the other day--as you know--I made the acquaintance of your father in Wales--at Pontystrad. I told him I had shown a young fellow some of those Gower caves and how his name was--like your father's, 'Williams.' Of course we soon came to an understanding. Then your father spoke of you in _high_ praise. What a delightful nature was yours, how considerate and kind you were--don't blush, though I admit it becomes you--Well you can pretty well guess how he went on. But what interested me particularly was his next admission: how different you were as a lad--rather more than the ordinary wild oats--eh? And how completely an absence in South Africa had changed you. You must forgive my cheek in dissecting your character like this. My excuse is that you yourself had rather vaguely referred to some wound or blood poisoning or operation, on the jaw or the throat. Not to beat about the bush any more, the idea came into my mind that _if_ in some way the knife or the enemy's bullet had interfered with your thyroid gland--Twig what I mean? I mean, that if your old man has not been exaggerating and that the difference between the naughty boy whom he sent up to London in--what was it? 1896?--and the perfectly behaved, good sort of chap that you are _now_ is no more than what usually happens when young men lose their cubbishness, _why_--_why_--do you take me?--I ask myself whether the change had come about through some interference with the thyroid gland. Do you understand? And I thought, seeing how intensely interesting this research has become, you might have told me more about it. Just what _did_ happen to you; where you were wounded, who attended to you, what operation was performed on the throat--only the rum thing is there seems to be no scar--well: now _you_ help me out, that is unless you feel more inclined to say, 'What the _hell_ does it matter to _you_?'"... David by this time has grown scarlet with embarrassment and confusion. But he endeavoured to meet the situation.