"Isn't it rather late in the day to find that out?" she interrupted sarcastically; but he ignored the interruption. "You must see for yourself, now that you are face to face with the thing, that it is impossible. It's quite unthinkable that you can wander for the next month all alone in the desert with those damned niggers. Though my legal guardianship over you terminated last September I still have some moral obligations towards you. Though it has been convenient to me to bring you up as a boy and to regard you in the light of a younger brother instead of a sister, we cannot get away from the fact that you are a woman, and a very young woman. There are certain things a young woman cannot do. If you had been the boy I always wished you were it would have been a different matter, but you are not a boy, and the whole thing is impossible--utterly impossible." There was a fretful impatience in his voice. Diana lit a cigarette slowly, and swung round on her chair with a hard laugh. "If I had not lived with you all my life, Aubrey, I should really be impressed with your brotherly solicitude; I should think you really meant it. But knowing you as I do, I know that it is not anxiety on my behalf that is prompting you, but the disinclination that you have to travel alone without me. You have come to depend on me to save you certain annoyances and inconveniences that always occur in travelling. You were more honest in Biskra when you only objected to my trip without giving reasons. Why have you waited until to-night to give me those reasons?" "Because I thought that here, at least, you would have sense enough to see them. In Biskra it was impossible to argue with you. You made your own arrangements against my wishes. I left it, feeling convinced that the impossibility of it would be brought home to you here, and that you would see for yourself that it was out of the question. Diana, give up this insane trip." "I will not." "I've a thundering good mind to make you." "You can't. I'm my own mistress. You have no right over me at all. You have no claim on me. You haven't even that of ordinary brotherly affection, for you have never given me any, so you cannot expect it from me. We needn't make any pretence about it, I am not going to argue any more. I will not go back to Biskra." "If you are afraid of being laughed at----" he sneered; but she took him up swiftly. "I am not afraid of being laughed at. Only cowards are afraid of that, and I am not a coward." "Diana, listen to reason!" "Aubrey! I have said my last word. Nothing will alter my determination to go on this trip. Your arguments do not convince me, who know you. It is your own considerations and not mine that are at the bottom of your remonstrances. You do not deny it, because you can't, because it is true." They were facing each other across the little table. An angry flush rose in Sir Aubrey's face, and his eyeglass fell with a little sharp tinkle against a waistcoat button.