Late that night, when Hetherwick was thinking things over, a pounding on his stairs and a knock on his outer door heralded the entrance of Matherfield, who, with an expressive look, flung himself into the nearest easy chair.  
"For heaven's sake, Mr. Hetherwick, give me a drop of that whisky!" he exclaimed. "I'm dead beat—and dead disappointed, too! Such a day as I've had after that woman! And what it all means the Lord only knows—I don't!"
 
Hetherwick helped his evidently far-spent visitor to a whisky and soda, and waited until he had taken a hearty pull at it. Then he resumed his own seat and took up his pipe.
 
"I gather that you haven't had a very successful day, Matherfield?" he suggested. "Hope it wasn't exactly a wild-goose chase?"
 
"That's just about what it comes to, then!" exclaimed Matherfield. "Anyway, after taking no end of trouble she got clear away, practically under my very nose! But I'll tell you all about it; that's what I dropped in for. When I went out of that house in St. Mary's Terrace, she was just turning the corner to the right, Bishop's Road way. Of course I followed. She went over the bridge—the big railway bridge—and at the end turned down to Paddington Station. I concluded then that she was going up by some early morning train. She entered the station by the first-class booking office; I was not so many yards in her rear then. But instead of stopping there and taking a ticket she went right through, crossed the station to the arrival platform and signalled to a taxi-cab. In another minute she was in it, and off. Very luckily there was another cab close by. I hailed that and told the driver to keep the first cab in sight and follow it to wherever it went. So off we went again, on another pursuit! And it ended at another terminus—Waterloo!"
 
"Going home, I suppose," remarked Hetherwick, as Matherfield paused to take up his glass. "You can get to Dorking from Waterloo."
 
"She wasn't going to any Dorking!" answered Matherfield. "I soon found that out. Early as it was, there were a lot of people at Waterloo, and when she went to the ticket office I contrived to be close behind her—close enough, at any rate, to overhear anything she said. She asked for a first single to Southampton."
 
"Southampton!" exclaimed Hetherwick. "Um!"
 
"Southampton!" repeated Matherfield. "First single for Southampton. She took the ticket and walked away, looking neither right nor left; she never glanced at me. Well, as I said yesterday, I don't believe in starting out on anything unless I go clean through with it. So after a minute's thought I booked for Southampton—third. Then I went out and looked at the notice board. Southampton, 5.40. It was then 5.25. So I went to the telephone office, rang up our head-quarters and told 'em I was after something and they needn't expect to see me all day. Then I bought a time-table and a newspaper or two at the bookstall, just opening, and went to the train. There were a lot of people travelling by it. The train hadn't come up to the platform then; when it came down a minute or two later I watched her get in; she was good to spot because of her tall figure. I got into a smoker, a bit lower down, and in due course off we went, me wondering, to tell you the truth, precisely why I was going! But I was going—wherever she went."
 
"Even out of the country?" asked Hetherwick, with a smile.
 
"Aye, I thought of that!" assented Matherfield. "She might be slinging her hook for anything I knew. That made me turn to the steamship news in the paper, and I saw then that the Tartaric was due to leave Southampton for New York about two o'clock that very afternoon. Well, there were more improbable things than that she meant to go by it, for reasons of her own, especially if she really is the Mrs. Whittingham of the Sellithwaite affair ten years ago. You see, I thought it out like this—granting she's Mrs. Whittingham, that was, she'll be astute enough to know that there's no time-limit to a criminal prosecution in this country, and that she's still liable to arrest, prosecution, and conviction; she'd probably know, too, that this Hannaford affair has somehow drawn fresh attention to her little matter, and that she's in danger. Again, I'd been working out an idea about her and this man Baseverie. How do we know that Baseverie wasn't an accomplice of hers in that Sellithwaite fraud? In most cases of that sort the woman has an accomplice somewhere in the background—Baseverie may have been mixed with her then. And now he may have information that has led him to warn her to make herself scarce, eh?"
 
"There's something in that, Matherfield," admitted Hetherwick. "Yes—decidedly something."
 
"There may be a good deal," affirmed Matherfield. "You see, we've let those newspaper chaps have a lot of information. I'm a believer in making use of the Press; it's a valuable aid sometimes, perhaps generally, but there are other times when you can do too much of it: it's a sort of giving valuable aid to the enemy. I don't know whether we haven't let those reporters know too much in this case. We've let 'em know, for instance, about the portrait found in Hannaford's pocket-book, and about the sealed packet in which, we believe, was the secret of his patent: all that's been in the papers, though, to be sure, they didn't make much copy out of it. Still, there was enough for anybody who followed the case closely. Now, supposing that Baseverie was Mrs. Whittingham's accomplice ten years ago, and that he'd read all this and seen the reproduction of the portrait, wouldn't he see that she was in some danger and warn her? I think it likely, and I wish we hadn't been quite so free with our news for those paper chaps. I'm glad, anyhow, that there's one thing I haven't told 'em of—that medicine bottle found at Granett's! There's nobody but me, you, and the medical men know of that, so far."
 
"You think this woman—Lady Riversreade as she is, Mrs. Whittingham as she used to be—was making off to Southampton, and possibly farther, on a hint from Baseverie?" said Hetherwick ruminatively.
 
"Put it this way," replied Matherfield. "Of course, you've got to assume a lot, but we can't do without assuming things in this business. Lady Riversreade was formerly Mrs. Whittingham. Mrs. Whittingham did a clever bit of fraud at Sellithwaite, and got away with the swag. Baseverie was her accomplice. Now then, ten years later Mrs. Whittingham has become my Lady Riversreade, a very wealthy woman. She's suddenly visited by Baseverie at Riversreade Court, and is obviously upset by his first visit. He comes again. Three nights later she's seen to come out of a club which he frequents. She spends most of the night in a flat in a quiet part of London, and next morning slopes off as early as five o'clock to a port—Southampton. What inference is to be drawn? That her visit to Southampton has certainly something to do with Baseverie's visits to her and her visit to Vivian's!"
 
"I think there's something in that, too," said Hetherwick, "But—we're on the way to Southampton. Go on!"
 
"Very good train, that," continued Matherfield. "We got to Southampton just before eight—a minute or two late. I was wanting something to eat and drink by that time, and I was glad to see my lady turn into the refreshment-room as soon as she left her carriage. So did I. I knew she'd never suspect a quiet, ordinary man like me; if she deigned to give me a glance—she's a very haughty-looking woman, I observed—she'd only take me for a commercial traveller. And we were not so far off each other in that room; she sat at a little table, having some tea and so on: I was at the counter. Of course, I never showed that I was taking any notice of her—but I got in two or three good, comprehensive inspections. Very good-looking, ............