“Clear, isn’t it? A beautiful clear brown. A tribute to the spring water here. You can see the house and all its windows through it, it is so perfectly transparent.” And he held it up, and shutting one eye stared through it with the other. “Well?” I inquired. “Well, now look at this.” And he took another glass and set it beside the first one, and poured both tea and milk into it. “Look there,” he said. I looked. “Jellaby,” said he. I stared. Then he took another glass, and poured both tea and milk into it, setting it in a line with the first two. “Browne,” said he. I stared. Then he took a fourth glass, and filled it in the same manner as the second and third and placed it at the end of the line. “Myself,” said he. I stared. “Can you see through either of those three?” he asked, tapping them one after the other. “No,” said I. “Now if I put a little more milk into them”--he did--“it makes no difference. They were muddy and thick before, and they remain muddy and thick. _But_”--and he held the milk jug impressively over the first glass--“if I put the least drop into this one”--he did--“see how visible it is. The admirable clearness is instantaneously dimmed. The pollution spreads at once. The entire glass, owing to that single drop, is altered, muddied, ruined.” “Well?” I inquired, as he paused and stared hard at me. “Well?” said he. “Do you not see?” “See what?” said I. “My point. It’s as clear as the first glass was before I put milk into it. The first glass, my dear Baron, is you, with your sound and perfect constitution.” I bowed. “Your splendid health.” I bowed. “Your magnificent physique.” I bowed. “The other three are myself, and Jellaby, and Browne.” He paused. “And the drop of milk,” he said slowly, “is the caravan tour.” I was confounded; and you, my hearers, will admit that I had every reason to be. Here was an example of what is rightly called irresistible logic, and a reasonable man dare not refuse, once he recognizes it, to bow in silence. Yet I felt very well. I said I did, after a pause during which I was realizing how unassailable Menzies-Legh’s position was, and endeavouring to reconcile its unassailableness with my own healthful sensations. “You can’t get away from facts,” he answered. “There they are.” And he indicated with his cigarette the four glasses and the milk jug. “But,” I repeated, “except for a natural foot-soreness I undoubtedly do feel very well.” “My dear Baron, it is obvious beyond all argument that the more absolutely well a person is the more easily he must be affected by the smallest upset, by the smallest variation in the environment to which he has got accustomed. Paradox, which plays so large a part in all truths, is rampant here. Those in perfect health are nearer than anybody else to being seriously ill. To keep well you must never be quite so.” He paused.