There was just a moment's hesitation. Did she once know, and had she forgotten? Or was she debating whether she would feign ignorance? He fancied the latter was the correct reason. "I don't remember, if I ever knew, the exact address, but it is somewhere in the direction of St Albans." Smeaton bowed himself out, and meditated deeply. "She's an artful customer, for all her innocent air, and knows more than she will tell, till she's forced," was his inward comment. "Now for two things--one, to find out what there is to be found at St Albans; two, to get on the track of the bearded man." CHAPTER SIX. JUST TOO LATE. Mr Smeaton was not a man to waste time. Within ten minutes of his arrival at Scotland Yard he had sent two sergeants of the C.I. Department to keep Mrs Saxton under close surveillance, and to note the coming and going of all visitors. As her flat was on the ground floor, observation would be rendered comparatively easy. The evening's report was barren of incident. Mrs Saxton had remained at home. The only visitor had been a young man, answering to the description of James Farloe, her brother. He had called about dinner-time, and left a couple of hours later. For the moment Smeaton did not take Farloe very seriously into his calculations. Mrs Saxton would tell her brother all about his visit, and to interrogate him would be a waste of time. He would tell him nothing more about Stent than he had already learned. He had noticed, with his trained powers of observation which took in every detail at a glance, that there was a telephone in a corner of the small hall. If her connection with the mysterious Stent were less innocent than she had led him to believe, she would have plenty of time to communicate with this gentleman by means of that useful little instrument. Later, he instructed a third skilled subordinate to proceed the next morning in a car to St Albans, and institute discreet inquiries on the way. Afterwards, he thought of the two amateur detectives in Chesterfield Street, and smiled. Sheila was a charming girl, pathetically beautiful in her distress, and Wingate was a pleasant young fellow. So he would give them some encouragement. He wrote a charming little note, explaining what he had done with regard to Mrs Saxton. He suggested they should establish their headquarters at a small restaurant close by, lunch and dine there as often as they could. If occasion arose, they could co-operate with his own men, who would recognise them from his description. He concluded his letter with a brief resume of his conversation with Mrs Saxton. Poor souls, he thought, nothing was likely to come out of their zeal. But it would please them to think they were at least doing something towards the unravelling of the mystery. In this supposition he was destined to be agreeably disappointed in the next few hours.