Two
o'clock
He was more attentive when Susan , who waited upon us at lunch , volunteered the information that she believed Mr. Smith had been out for a walk yesterday morning , and that he had only returned half an hour before the tragedy occurred . I could not myself see the bearing of this incident , but I clearly perceived that Holmes was weaving it into the general scheme which he had formed in his brain . Suddenly he sprang from his chair and glanced at his watch . `` Two o'clock , gentlemen , '' said he . `` We must go up and have it out with our friend the Professor . '' 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 .