said Summerlee harshly. "Well, it's at the bottom of this oxygen business, or I am mistaken," said I. "Stuff and nonsense!" cried Summerlee again with quite unnecessary violence. We had all got into a first-class smoker, and he had already lit the short and charred old briar pipe which seemed to singe the end of his long, aggressive nose. "Friend Challenger is a clever man," said he with great vehemence. "No one can deny it. It's a fool that denies it. Look at his hat. There's a sixty-ounce brain inside it--a big engine, running smooth, and turning out clean work. Show me the engine-house and I'll tell you the size of the engine. But he is a born charlatan--you've heard me tell him so to his face--a born charlatan, with a kind of dramatic trick of jumping into the limelight. Things are quiet, so friend Challenger sees a chance to set the public talking about him. You don't imagine that he seriously believes all this nonsense about a change in the ether and a danger to the human race? Was ever such a cock-and-bull story in this life?"He sat like an old white raven, croaking and shaking with sardonic laughter. A wave of anger passed through me as I listened to Summerlee. It was disgraceful that he should speak thus of the leader who had been the source of all our fame and given us such an experience as no men have ever enjoyed. I had opened my mouth to utter some hot retort, when Lord John got before me. "You had a scrap once before with old man Challenger," said he sternly, "and you were down and out inside ten seconds. It seems to me, Professor Summerlee, he's beyond your class, and the best you can do with him is to walk wide and leave him alone." "Besides," said I, "he has been a good friend to every one of us. Whatever his faults may be, he is as straight as a line, and I don't believe he ever speaks evil of his comrades behind their backs." "Well said, young fellah-my-lad," said Lord John Roxton. Then, with a kindly smile, he slapped Professor Summerlee upon his shoulder. "Come, Herr Professor, we're not going to quarrel at this time of day. We've seen too much together. But keep off the grass when you get near Challenger, for this young fellah and I have a bit of a weakness for the old dear." But Summerlee was in no humour for compromise. His face was screwed up in rigid disapproval, and thick curls of angry smoke rolled up from his pipe. "As to you, Lord John Roxton," he creaked, "your opinion upon a matter of science is of as much value in my eyes as my views upon a new type of shot-gun would be in yours. I