But Margaret pondered these things.
She saw quickly that Barker had perceived that some embarrassment existed, and was spending his best strength in trying to make the meal a particularly gay one.

But she could not understand how Barker could have found out that there was any difficulty.

Had Claudius been making confidences?
It would have been very foolish for him to do so, and besides, Claudius was not the man to make confidences.

He was reticent and cold as a rule, and Barker had more than once confessed to the Countess that he knew very little of Claudius's previous history, because the latter "never talked," and would not always answer questions.

So she came to the conclusion that Barker only suspected something, because the Doctor had not been with her during the day.