About noon--I saw no one but blacks in the meanwhile--the Captain came with a letter. "From Sir Robert--catch!" said he. I tore it open. A single sheet of note enclosed a cheque signed in blank. "Dear Dr. Pinsent," ran the letter. "You will find that my signature will be honoured for any sum it may please you to put upon my life in your esteem. Permit me to express a hope that you will not hurt my vanity in your selection of numerals. "Sincerely yours, ROBERT OTTLEY." I handed the note to Weldon. He read it and whistled loud and long. "You might beggar him!" he cried. "The man is stark mad." "Either that or he has made a truly wonderful discovery," I rejoined. "And there is Belleville to consider. That man, I fancy, is a rascal--but also a sane one." "It has me beat," said the handsome Captain. "The whole thing from start to finish. Ottley is up there now spooning his daughter like a lover. He was as sweet as pie to me, too. I feel like a stranded jelly-fish. What will you do?" I enclosed the cheque in a blank cover, sealed it and gave it to the Captain. "Will you be my courier?" "Of course," said he, and swung off. He returned at the end of my third cigar, with a second letter. It ran, "My dear young friend, Your refusal has deeply pained me. The more, because it deprives me of the pleasure of your company on the road to Cairo. I beg you, nevertheless, to choose from my stores all that you may require that may serve you during your continued sojourn at Rakh. We start at sunset for the Nile and north. "Ever yours attachedly, "R. OTTLEY." When the Captain had mastered this precious effusion, he collapsed upon a stool. "He intends to leave you here alone in the desert. It's--it's marooning, nothing less!" he gasped. I lighted a fourth cigar and lay back thinking hard. In ten minutes I had made up my mind. I sat up. The Captain was anxiously watching me. "See here, my lad," I said, "in that bundle yonder is the manuscript of a book I have been working hard upon for three years and more. It is the very heart of me. Take good care of it. One of these days--if I live--I'll call for it at your diggings in London. I have your address in my notebook." "Oh! Oh! Oh!" said the Captain. "But what's the game?" "Diamond cut diamond. I'm going a journey. But I'll say no more. Mad or sane, you are eating Ottley's salt, and are beholden to him for his paternity of the exceptionally gifted young woman you propose to marry. Good-bye to you." I held out my hand. He sprang up and wrung it hard. "You are sure you are doing right?" he asked. I filled my pockets with his cigars. "I am sure of nothing," I replied, as I did so, "except this--I have been abominably ill-used by a man who under Heaven owes his life to me--and this--I resent it." I put on my helmet, nodded and left the tent.