His keen observation, aided by his accurate knowledge of his client's character, had plainly revealed to him what was passing in Lady Lydiard's mind.
She had entered the house, feeling (perhaps unconsciously) a jealousy of Miss Pink, as her predecessor in Isabel's affections, and as the natural protectress of the girl under existing circumstances.

Miss Pink's reception of her dog had additionally irritated the old lady.

She had taken a malicious pleasure in shocking the schoolmistress's sense of propriety--and she was now only too ready to proceed to further extremities on the delicate question of Isabel's justification for leaving her house.

For Isabel's own sake, therefore--to say nothing of other reasons--it was urgently desirable to keep the peace between the two ladies.

With this excellent object in view, Mr.Troy seized his opportunity of striking into the conversation for the first time.
"Pardon me, Lady Lydiard," he said, "you are speaking of a subject which has been already sufficiently discussed between Miss Pink and myself.