The old man had just finished his lunch, and certainly his empty dish bore evidence to the good appetite with which his housekeeper had credited him. He was, indeed, a weird figure as he turned his white mane and his glowing eyes towards us. The eternal cigarette smouldered in his mouth. He had been dressed and was seated in an armchair by the fire.

“Well, Mr. Holmes, have you solved this mystery yet?” He shoved the large tin of cigarettes which stood on a table beside him towards my companion. Holmes stretched out his hand at the same moment, and between them they tipped the box over the edge. For a minute or two we were all on our knees retrieving stray cigarettes from impossible places. When we rose again, I observed Holmes’s eyes were shining and his cheeks tinged with colour. Only at a crisis have I seen those battle-signals flying.

“Yes,” said he, “I have solved it.”