'Our interests,' he remarked, 'should not be far apart.' 'If I were sure of that,' she declared, 'the rest would be easy. I am for France and for France only. You are for America, and, I am afraid, for America only.' 'Chance, in this instance,' he ventured, 'has at any rate made us allies.' 'I should like to feel quite sure about that,' she said. 'If you are not busy, will you walk with me on to the Embankment?' They strolled down the narrow street and found a seat in the gardens. 'Between thieves,' she continued, looking him in the face, 'there is sometimes honour. Why not amongst those who are engaged upon affairs which, if not nefarious, are at least secret? Let us see whether we can be allies, and, if not, where our interests clash. You know perfectly well, as I do, that Jules murdered that little chemist from Chicago and stole the formula. You know very well that the suite in which you take so much interest in the Milan Mansions, belongs to Jules. You know very well that he was arrested there a quarter of an hour after he left the hotel, and that he had had no time to dispose of the formula. You know that the place has been searched, inch by inch, but that the formula has not been found.' 'I have just arrived exactly as far as that myself,' Lavendale assented mendaciously. 'You are some time behind me, but it is true that we have arrived at the same point,' she continued. 'Now the question is, can we work together? What should you do with the formula if ever it came into your possession?' His lips tightened. 'I cannot tell you that,' he said firmly. 'I believe that I know,' she went on. 'Well, let me put you to the test.' She opened a black silk bag which she was carrying, a little trifle with white velvet lining and turquoise clasp. From a very dainty pocket-book in the interior she drew out a crumpled sheet of paper, covered with strange, cabalistic signs. She smoothed it out upon her knee and handed it to him. 'Well,' she exclaimed, 'there it is! Now you shall tell me what you are going to do with it?' His hand had closed over the piece of paper. He gripped it firmly. Before she could stop him he had transferred it to his own pocket. She shrugged her shoulders. 'You had better return it to me,' she advised. 'I shall not,' he replied. 'Forgive me. I did not ask you for the formula--I did not know you had discovered it--but since I have it, I want you to remember that it was the discovery of an American and I shall keep it for my country.' 'But your country is not in need of anything of the sort,' she protested.