But Boirac had been actually seen telephoning from Charenton. For a moment the detective’s spirits fell. But he felt he must be right so far. Some explanation of the difficulty would occur to him. And it did. The waiter had believed Boirac was there on _Monday_. And he must have been! In some way he must have faked the telephoning. There could be nothing else for it. Another point occurred to him. Surely, he thought, the telephone operator always mentions the name of the calling town in inter-urban calls? If Boirac had called up his office from Calais, would not the operator have said, ‘Calais wants you’? If so, how had the manufacturer been able to deceive his butler and chief clerk? This was undoubtedly a difficulty. But he put it on one side as he began to think how this new theory could be tested. First he would go again to the Charenton waiter and explain the importance of settling the day on which Boirac lunched. Perhaps the man would now be able to recall some circumstance which would make this clear. Next he would find out from François and Dufresne whether any phrase such as ‘Calais wants you’ had been used by the telephone operator. This inquiry, he noted, must be made with great skill, so as to avoid rousing Boirac’s suspicions should either man repeat the conversation. From the telephone central at Calais, if not at Paris, he could doubtless find if calls were made from the former town to the latter at the hour in question, and he might also find that some one answering to the description of Boirac had made those calls. Finally, it might be possible at Ostend to get information about the Brussels call. Inquiries on these points should reveal enough to either confirm or disprove his theory. The next morning therefore saw La Touche again in the café at Charenton in conversation with the waiter. ‘The point as to which day the gentleman was here has become important,’ he explained, ‘and I shall hand you another twenty francs if you can settle it.’ The man was evidently anxious to earn the money. He thought earnestly for some time, but at last had to confess he could recall nothing fixing the date. ‘Do you remember what he had to eat? Would that help you?’ asked the detective. The waiter shook his head after consideration. ‘Or any little matter of a clean cloth or napkin or anything of that kind? No? Or any other person who was in at the same time, or to whom you may have spoken on the subject?’ Again the man shook his head. Then suddenly a look of satisfaction passed over his face. ‘But yes, monsieur,’ he said eagerly, ‘I remember now. What you have just asked me brings it to my mind. M. Pascot lunched also when the gentleman was here, and he noticed him and asked me if I knew who he was. M. Pascot may be able to tell us.’ ‘Who is M. Pascot?’