As to the usual course of taking people in custody on suspicion, going before the magistrate, and all the rest of it--nothing of the sort was to be thought of, when your ladyship's daughter was (as I believed) at the bottom of the whole business.
In this case, I felt that a person of Mr.Betteredge's character and position in the house--knowing the servants as he did, and having the honour of the family at heart--would be safer to take as an assistant than any other person whom I could lay my hand on.

I should have tried Mr.Blake as well--but for one obstacle in the way.

HE saw the drift of my proceedings at a very early date; and, with his interest in Miss Verinder, any mutual understanding was impossible between him and me.
I trouble your ladyship with these particulars to show you that I have kept the family secret within the family circle.

I am the only outsider who knows it--and my professional existence depends on holding my tongue." Here I felt that my professional existence depended on not holding my tongue.

To be held up before my mistress, in my old age, as a sort of deputy-policeman, was, once again, more than my Christianity was strong enough to bear.
"I beg to inform your ladyship," I said, "that I never, to my knowledge, helped this abominable detective business, in any way, from first to last; and I summon Sergeant Cuff to contradict me, if he dares!" Having given vent in those words, I felt greatly relieved.