"Oh, no, there was no question about it. He had family papers which only the nephew could possibly have, and you may depend the Yorkshire Rusholms would have found a flaw in the title if they could. Their disappointment must have been great, and if I could discover that Sir Grenville had an enemy amongst them—some relation he had refused to help, for instance—I should want to know all about him."

"Yours is a very interesting idea," said Quarles. "Do you happen to know who Lady Rusholm was?"

"The daughter of a tea planter in Ceylon. Her social success here has been very great, as you know."

"A very charming woman I should say," said the professor. "I saw her once—not many months ago. She was distributing the prizes at a technical institute in North London. I remember how well she spoke, and what an exceedingly poor second the chairman was in spite of his being a Member of Parliament. You have got a constable at The Lodge, I suppose?"

"Two. I have given instructions that no one is to be allowed in the room, on any pretext whatever."

"Good. You and I will go there to-morrow. I'll be your assistant, Wigan—say an expert in finger prints. I'll meet you outside The Lodge at ten o'clock. There are so many clues in this case, the difficulty is to know which one to follow, I must have a few quiet hours to decide."

I smiled. It was like Quarles to make such a statement, especially after I had declared that criminals were becoming cleverer. Never were clues more conspicuous by their absence, I imagine. I was, however, delighted to have the professor's help. It was like old times.

The next morning I met Quarles in Queen's Square, and his appearance was proof of his enthusiasm. He posed as rather a feeble, inquisitive old man who could talk of nothing but finger prints and their significance. Sir Arthur was evidently not impressed with his ability to solve any mystery. When we entered the drawing-room he seemed lost in admiration of the apartment, and did not even glance at the open coffin which stood on the trestles. He walked to the window, drew aside the blind, and looked into the garden. Then he looked into the small room.

"No other exit here but the window. An entrance might have been made by that window."

"The door between the two rooms was locked," said Sir Arthur. "I had to get the key from my mother when Mr. Wigan wanted to go in. It is my mother's special room, but she had been so occupied in nursing my father that she had not used it for more than a week."